Welcome to my world, my world of turbos, tyre smoke, and tuning...
Tuning cars, driving cars, testing parts, and complaining about everything. It's my job, and a the majority of my non-work life too...
As we all know and have experienced, the car world is a hive of bullshit and excuses, as people can never admit anything is their fault, so either blame the car or someone else.
From people blaming poor performance on a misfire when it's actually shit driving or them lying about how quick their car really is, to companies not honouring a warranty by making some kind of excuse to blame it on user-error- Excuses are a 'car thing'.
The inspiration for this mini-feature was hearing one of the most ridiculous excuses I've ever heard, and something that I'd not heard for about 15 years, and even back then it blew my mind someone supposedly respected had the balls to claim this...
Step back to 15 or so years ago, and the first example of this was about the Skyline GT-R RB26DETT engine, and most notably the ceramic turbine wheels the turbos have, which are known to snap off the shaft or shatter to many pieces.
While the above is an unfortunate and common fact, one of the big name tuners of the time used to convince their followers they needed an engine reubild as soon as this happened, as bits of the turbine wheel will have been 'sucked' in to the engine.
Some of you right now might be thinking "Well can it?", and some others are thinking "WTF?", so let's break it down in to a way even a tuning novice can understand...
Fast forward to today, and I heard a very similar thing, used as another bullshit excuse, but actually even more far-fetched in my eyes.
The basic story is an engine has severe pitting (IMO severe detonation, but that doesn't matter for this) on the squish/quench pads on all cylinders on a turbocharged engne, and on the exact same opposite areas on the pistons too.
No marks anywere else- Untouched bores, untouched centres of pistons, untouched valves, untouched combustion chambers- Basically only the areas most affected by det.
Certain people (And to make it even more stupid, these people AREN'T the tuner either! This is honestly people just trying to defend him off their own back, despite it not being strictly blamed on him- Retarded or what) flatly refuse to see it as detonation, and claim it's FOD (Foriegn object damage), and back that up by the fact ONE of the cylinders has broken a piece of valve guide off in an inlet port.
My comment was "Even IF somehow it can only damage areas either side of the piston/chamber without touching the center or the bores, how can FOD in one cylinder account for the same damage in all the others?"
The reply was "Doesn't matter which cylinder was damaged, if one goes they're all going to get damaged as the metal will travel back up the inlet manifold and in to the other cylinders"
Again, some of you are already thinking "WTF", as it's probably even more far fetched than the first, despite being said by a bit of a hero of the tuning scene, so let's once again break it down...
So yeah, more utter shit.
The WORST thing about all this kind of crap is though, is that this isn't words of random idiots, the 2nd example wasn't even from a tuner making an excuse either- This is coming from RESPECTED names in the modified car world, 'FAMOUS' names some might say, and because they're "Somebody", people blindly believe them, despite it being insanely far fetched.
My question of it all is, do they BELEIVE what they're saying, or are they LYING? Either way it is REALLY fucking bad considering they're influential, aspirational, whatever the fuck you want to call them, names, in this stupid hobby we all have.
And this is exaclty why I'm hugely skeptical of what even 'Big' names say, partly by being untrustworthy, partly by not knowing as much as you think (or they'd like you to think) they'd know.
It's terrible really, being a skeptic or having trust issues isn't a good thing, and it'd be amazing if this tuning world was just people being honest and helping, but instead the kind of people and the kind of advice in the tuning scene is a big reason why so much of it is fucking awful and so slow progressing.
You have 2 choices, you can either listen to these people and be one of the crowd getting ripped off or having mediocre stuff, or you can take everything you hear with a pinch (ok, a fucking huge road gritter full) of salt, and fact check stuff from even supposed big and trustworthy names, which should, while it's a lot of work, get you a seriously good car.
While it's popularity and media coverage is increasing in recent years (Yet it was on prime time TV on in the 70s and 80s- A long way to go before it's back at this level!), Rallycross is, in my eyes anyhow, the most under-rated motorsport there is.
And more than under-rated, it's genuinely fun to watch, and by far the most relevant to UK tuning fans of any motorsport.
Formula One is world famous and has the biggest budget of any motorsport, but is it exciting to watch? Not really. And it's all so secret that any possible relevance to the tuning we all do we either won't know about for decades, or never will.
WRC cars in 2017 will be the most powerful than they've been since the GroupB days, but it's still not a great spectator sport, despite being hugely famous and featuring wild cars.
BTCC is hugely popular in the UK, and as circuit racing goes, it's pretty badass, but in my eyes it's not even a patch on Rallycross, and strict rules make things quite samey too.
I've seen people talk about Rallycross like it's fucking Grasstrack oval racing, in fact I've seen the same people go "If you want to see a real mans sport, check out BTCC". FUCK knows what they've been watching, but it sounds like they've never seen Rallycross in their lives.
If you haven't watched any before, go check some out on YouTube or something. 600bhp 700lbft 2ltr flame throwing anti-lagged 4wd turbo cars door to door, sideways everywhere, on a twisty track which is a mix of tarmac and gravel. As the races only last 5 laps (It was usually 2.5 laps in the 80s/90s), so unlike most racing, it doesn't have boring parts where they're trying to save the car, or tyres, or engine- It's flat out from the start to the end.
Anyhow, as I love tuning (and presumably if you like Stav-Tech you love tuning too), the main reason I love Rallycross is the insane acceleration of these things, and that's because the engines are fucking MENTAL...
In recent years engines in the top class are restricted to 2ltr (turbo, of course!) and with a 45mm inlet restrictor, which keeps power back to around 600bhp and 700lbft of torque, though previously there was no restrictor as such, but instead different minimum weight classes depending on engine capacity.
Things did vary country to country, year to year, but for example, in the late 80s early 90s in the UK, the 4ltr class, which mostly consisted of 2.3ltr turbo engine cars (turbo or supercharged meant a multiplication factor of 1.7, and 2.3x1.7 is a touch under 4ltr), had a 1100kg minimum weight limit.
Cars in this class were things like Will Gollop's Metro 6R4 which was the V6 de-stroked to 2.3ltr then twin turbos added, giving it 750-800bhp, and other similar crazyness, such as the 4wd Turbo E30 BMW M3 of Arild Martinsten which also had 750bhp+
Due to the various weight vs capacity classes, it was common to see 1.4ltr to 3ltr+ cars all in the same race, and due to the lighter weights and the fact almost everyone had BIG turbos fitted, everything was, just like it is now, fucking mental fast.
You'd imagine maybe that everyone would be aiming for the 2.3ltr turbo engine for the maximum power, but this wasn't actually the case, as these were days before seriously effective ALS systems, so power was always a trade-off with lag, and also, when it boils down to it, on a slippery gravel surface with few straights there's not much grip or opportunity to use big power.
It was often said that around 550bhp was the maximum usable power, and many ex-GrpB cars either stayed at, or were even de-stroked to around 1.8ltr, which was enough for their 550bhp power goal, but allowed them to be much lighter than the 2.3ltr turbo cars.
Having said this, there were some cars with MUCH more power, 750bhp+, but if you watch old Rallycross videos on YouTube it was spectacular but unless they were in the lead it was very little use on the twisting tracks, and usually have about a 2second oppertunity of full power per lap!
Here's a few older rallycross engines. I say a few, as despite the wonders of the internet, it's not a time machine, so despite some pics being uploaded from the 80s and early 90s, there are literally NO pics around of some of the greatest, wildest, and most interesting rallycross engines ever made.
Gollops twin turbo 6R4 lump? Nope. Martinsetens F1 Turbo M3 lump? Nope. All the countless Group B 205 T16s, Delta S4s, Audis, etc made better than ever that ran in Rallycross? Nope. Unfortunately there's very few pics out there on internet land, which really annoys me, but here's a few...
In the 80s Renault Gordini turbo engines (Which are, in essence, the Renault 5 GT Turbo engines, but with a better, crossflow, cylinder head), from 1.4 to 1.6ltr were popular and used in both Renault and Volvo rallycross cars, often pushing well over 350bhp, and as they were fitted to cars that weighed well under 900kg, it's fair to say they went like hell.
Another mega successful and popular engine in the 80s and even 90s were turbo'd versions of Ford BDA lumps, often built by Zakspeed, from 1700cc upwards, and pushing out well in excess of 500bhp.
Beetles were popular in 80s rallycross too, with all kinds of specs, including 4wd turbo versions, like this one that's still around to this day...
Most interesting about this one is the engine, which is still a VW block, but as Rallycross rules allow any heads to be fitted, it's got Subaru heads...
One thing I'd like to know, and I've yet to see pics or info confirming it, is turbo position on this Beetle. Going by what I can see, I'd say it's mounted inside the car, where the rear seats would normally be, which is pretty cool. In fact I 'think' you can just about see it through the hole in the bulkhead on this pic...
Rallycross gave a new lease of life for the Group B cars after they were banned from rallying too, showing what they could have been like with more development, making them wilder than they ever were in rallying. Check out this Citroen BX4TC. They were rubbish in GrpB due to lack of development, a total disaster, but in rallycross it got it's chance to be as mad as it should've been, and they were fucking weapons...
If you're wondering how batshit crazy fast these cars were, even in the mid 80s, check out this article from 1984. No it's not in English, but enough of it is written in words we understand to get the rough idea of the 1984 spec of Rallycross legend Matti Alamaki's Porsche rallycross car...
So this is 1984, and this Porsche 930 has 4 wheel drive, a twin turbo 3.2ltr flat six pushing out 750bhp and 6200rpm, and weighs, well, 1130kg I think? Check out the old-skool timing gear wheel on the back in the main pic too! Now page two...
0-62mph in 3.1sec (so 3sec dead to 60mph), 0-100mph (160kmh) in 5.7sec, and 10.5sec quarter mile time. And this is 1984, 32 bloody years ago!
EDIT!!! You might think the above acceleration sounds mad, and it is, but according to one of our helpful Finnish readers (who can read the above words, unlike me lol), those times were not only done in the WET, but the cars stop speed is 206kmh and hit it by just 260m, so did the last 140m just bouncing off the rev limiter in top, no more acceleration!
So if it had the gearing for it, and a dry surface, that car is easily in the 2s to 60mph, 4s to 100mph, and running 9second quarter miles.
In 1984, and not remotely a straight line drag car. Crazy shit right there.
Rallycross is also where you see the engines that, while we all NOW know are massively tunable, have often been tuned to 600bhp+ for decades already. But as most people don't notice race engines, and just look at tuner cars for inspiration, people never realise. Like Saab lumps...
Or the Opel/Vauxhall C20XE...
Rallycross is amazingly unknown by tuning fans in the UK, and to me I find that fucking bizarre, as frankly, the engines are THE most relatable to the shit they do of any motorsport; just usually way, way better.
I mean, look at all these engines so far, they are ALL stuff you'd recognise from typical big power tuned engines we love to see in road/drift/timeattack cars, but frankly, these are usually done far far better, and cleverer, by people who know what they're doing rather than just pretend to.
Not many parts on Rallycross engines are bits you recognize as the big money off the shelf tuner parts everyone likes to fit to their road cars though, as funnily enough, despite the hype, those bits are rarely, if ever, the best designs.
That to me is a big reason why I love Rallycross- The engines are something I know, understand, relate to, agree with the design, and more to the point, they're my inspiration when tuning- Not some nobhead with a lockup who calls himself a tuner.
THESE are the engines you should look up to in my eyes, not some shiny shit you see on FB, but more on this later...
ANYHOW, moving on to the '00s to present day, Rallycross top classes around the world mostly changed to a 2ltr turbo class with an inlet restrictor (This was in 1997 if I remember right in Europe, and maybe 2003 in the UK?) to hold back power to vaguely sensible levels as things were getting ridiculous (and frankly, with today's tech, a 2.3 non-restricted turbo engine like the old days, would now have about 1200bhp, and costs would be fucking insane), though this 'vaguely sensible' level is still about 600bhp and 700lbft, which frankly is insane fast, like '0-60 in sub 2sec on tarmac' sort of fast.
This is the usual 45mm turbo inlet restrictor fitted...
Though at least once a twin turbo setup was attempted, which meant two smaller restrictors instead...
One other big advantage the newer (and by that I mean in the last 15yr or so) engines have, despite less power than some of 80s ones, is fucking everything has something very noticeable fitted, usually a setup made Swedish company Tibuc...
What the above is, well, the 2 blue hoses coming from the box on top of the plenum to the box after the throttles, is the electronic adjustable air bypass valve, a fucking big air bypass too, for the anti-lag system. And ALS is, if you speak to most Rallycross drivers these days, is THE most important part of the engine.
The engine performance difference ALS makes is an incredibly hard thing to imagine unless you've experienced a really seriously good working system yourself, but the difference between it being on and off is like two different engines, and the difference between being competitive and not in Rallycross.
Realistically, the 2ltr turbo engines of current cars, without ALS activated, are going to have a powerband of 4000rpm+ and not the most responsive things when on and off throttle either, as the turbos fitted are BIG.
A small high rpm powerband and poor throttle response is NOT ideal for Rallycross, which is incredibly close and tight, on and off throttle constantly, and where a whole lot of the cars steering done with the gas pedal rather than the steering wheel.
Basically, if you switch the ALS off on a Rallycross car they will get left for dead by the other cars with it active; you just can't compete without it.
With ALS on (and Rallycross ALS is mental, like full boost all the time regardless of revs and throttle position style, proper fucking mental), the cars are totally different animals, like driving an 12ltr+ naturally aspirated engine that somehow also revs really high, rather than a typical 2ltr big turbo engine- Basically you get BIG torque and instant response constantly, regardless of revs.
Some more pics, all with Tibuc ALS setups, as almost everything had/has it...
As the above pics might hint, Cossie YB engines dominated Rallycross from the late 90s until recent years, as despite what the Jap fanboys etc like to think, if you wanted a 2ltr engine that could bash out 600bhp/700lbft and win you races, the YB was the one to have. How many SR20s have you seen in Rallycross? I can think of one tbf, in Finland, in a Mazda RX7..
But again, variety has always been key, I mean, here's a Mitsubishi 4G63...
And here's a VW lump...
Going bang up to date now to the present day, while the engines are the same principle, some of the ALS systems are even more advanced, more like mega power versions of current WRC engines, and now the airflow bypass isn't just past the throttles (though it usually is too, via fly-by-wire throttles now though more often than not), but it's direct in to the exhaust manifold via a valve and a series of pipes, which is more efficient.
This particular ALS system isn't actually new though, the earliest versions of this were used on the Audi Group B rally car in the mid 80s.
This ALS system is the valve at the front by the exhaust manifold on the below pics, and the small bore pipes from it is feeding air to each exhaust runner.
Anyhow, regardless of age, the fundamentals of turbo Rallycross engines hasn't changed in 30odd years, and they're still fucking awesome and even the oldest ones should be the inspiration to most of us tuning turbo cars in my eyes.
I'm not saying copy them exactly, as I dunno about you but I sure as shit can't afford to build a 700bhp/700lbft 4cyl turbo crazy thing, but what I mean is check them out, check out what they do and often DON'T do, as you can be sure as shit they do or don't do it as they know what's best.
Not sure what I mean? Well...
For example, people often get all giddy and excited telling the world about their amazing boost pipe clamps that cost them about 50quid each, and those same people tell the world jubilee clips are shit and don't hold under high boost, etc etc, usually despite the person saying this having a car that don't even run a lot of boost.
WELL, let's look at some Rallycross engines shall we? Money is NOT an issue for them, they are mega spec, the best of the best. The engines often run 3bar+ peak boost. But what holds the vast majority of their hoses on, from the early 80s to the present day? Yep, that's right, normal Jubilee clips.
YES, shit twisty soft Chinese shit fake Jubilees are junk, but proper ones are strong as hell, can be done up mental tight, and hold a fuck sight better than most the wide Mikalor etc etc ones people like to shout about loudly on the internet.
What about massive fuckoff inlet plenums like so many people pay big bucks for on their tuned road cars with barely 200bhp per litre? Well, these Rallycross cars are 300bhp/litre+ and do they have massive plenums? Fuck no, as there's nothing good to gain from it at all, and plenty to lose in response. A better than standard plenum? Yes. But IMO 80%+ of aftermarket plenums are just some badly designed, often oversized, shiney shit that does no good barring lighten your wallet.
I've mentioned it in the past, but what about big cone filters in the engine bay? If you listen to internet car experts, they suck in hot air and kill ruin performance, seemingly oblivious to the fact ENOUGH air matters 100 times more than COLD air. Thankfully Rallycross people aren't keyboard tuners, and as the pics show, they put a massive air filter where ever it fits best.
Oh, here's a good one you can see in these pics that everyone in the tuned road car world ignores, fucking TURBO HANGERS.
On the internet you can't fail to read people constantly crying as their turbo manifold has cracked, or the bolts have worked loose, for the 20th time this month.
What gets me is peoples solutions, or advice, are all kinds of crap, such as fancy bolts and fasteners, different exhaust designs, even fucking welding the turbo straight to the manifold like they're auditioning for fucking Roadkill or something.
But despite all this, never do they have the sense to look at pretty much ANY proper race car and notice they fucking ALL run turbo hangers, taking the weight of that bloody turbo off the exhaust manifold, off the exhaust system, off the exhaust nuts, and bolts, and studs, and gaskets, and everything else that fucking breaks. And lo and behold this stops them breaking.
Dunno if I ever mentioned it before on here, but on my old Cossie (they have a form of turbo hanger fitted as standard, nothing fancy, but they have them) I ran 2 years no issue at all without anything blowing, leaking, cracking, anything, despite 30psi boost, anti-lag, and serious abuse. THEN my turbo hanger got a bit tired looking so I removed it to sort it out, presuming it'd be fine without it for a bit (this was like 2002, I knew no better), and within a WEEK it was blowing at a join due to loose bolts, and from then on it would loosen bolts or blow an exhaust gasket within a few days of doing them back up.
Refitted the hanger a week later and it never happened again.
That taught me a lesson for sure, but despite telling people for about 15 years since that their issues would be solved with a turbo hanger, does anyone listen? Do they fuck, you still never see 'em.
And the above are just a few examples of the many many many things just checking out some proper race car engines, and ignoring typical shitty tuner cars, will teach you.
And ignoring teaching you anything, go watch some fucking Rallycross, it's mental! There's tons of 80s, 90s, and current Rallycross all over Youtube, and in fact, if you wanna see the craziness of modern ALS on Rallycross cars, find some vids of the Gymkhana Grid Championship finals in Greece from last weekend (ie end of October), there was various Rallycross cars in that, most notably Liam Doran's Citroen. The finals was at night, so it's flames galore, and by the end of a 1min run the entire exhaust, right to both tailpipes, was glowing red hot- Properly amazing looking.
So yeah, Rallycross is awesome, and Rallycross engines are surprisingly educational AND awesome. Check them out...
In the UK and Europe, the Ford Pinto was about the most popular Ford engine to tune in the 70s, 80s, and early 90s, and to this day powers loads of fast road and race cars.
The Pinto has spawned loads of legendary variations, most famously the YB Cosworth engine, but also things like the Millington Diamond engines you see powering most top Mk1/2 Escort rally cars these days, among other things.
The thing is, while the Pinto was cheap and common, let's be honest, it wasn't that great, and didn't exactly set the tuning world on fire. Granted, it can be made to push out decent performance, and the bigger bucks and much rarer YB/Millington/Warrior/etc headed versions can be pretty insane, but for your average Joe road car tuner, once the 80s and 90s came along with various other, better, engine options, it just didn't cut the mustard; especially as there was very little serious turbo development done by tuners or racers on the basic 8 valve production Pinto engines.
In the USA though, they didn't get 'our' Pinto, but oddly, and on a similar time scale to our engines (ie early 1970s on), they got a very similar looking, but it turns out totally and utterly un-interchangeable engine, fitted to a car that was called the Ford Pinto. But the engine wasn't called a Pinto, the engine was the Ford Lima.
It looks like a Pinto, with it's inline 4cyl 8 valve setup and iron block and head, but the Lima is, aside from de-stroked race engines late small bore versions, 2.3ltr, 0.3ltr more than the biggest production Pinto, which is a bonus for tuning from the outset. In fact it's even more of a bonus than it first seems, as thanks to the engine design, the capacity can be increased hugely with stroker kits, with high revving engines up to 2.9ltr (just under 400bhp N/A!) have been built from the Lima.
Standard capacity is one bonus, but another is, like it or not, the Lima block seems to be a lot stronger than the production Pinto block too. Normal Pinto blocks are generally considered a liability above 400bhp (though more has been done, with some risking pushing the 205 block YBs beyond 500...), and beyond that it's generally the stronger (but interchangeable) YB Cosworth (4wd and RS500) blocks that are needed for the Euro Pintos.
The Lima block though? Well, 1000bhp+ has been known...
Another massive advantage is the Lima attracted a huge tuning and motorsport scene in the USA and South America, so unlike the Pinto, there's a large amount of tuning knowledge and parts out there enabling BIG power; especially with turbocharging them.
Perhaps the biggest single advantage though from a road car tuner point of view, is, from 1979 to 1989, it was sold as a factory turbocharged engine on a huge number of vehicles. This means it was not the lucky rich few who got to play with them, but your average Joe had no problem affording one, as they were cheap and relatively commonplace.
As always with road car tuning though, there's always the question of "Where IS the limit of this engine?" and without motorsport it's rarely found out. But just like the YB Cosworth engine we all know and love, the turbo Lima was used by the Ford Motorsport teams for their race engines too, which meant a whole shitload of expensive R+D the road tuners could never do was done for them by Ford, advancing the tuning scene massively...
In the early-mid 80s XR4TIs in the USA kicked quite a bit of ass in IMSA GTU racing using 2ltr 400bhp versions of these engine, still using the factory iron heads etc etc, but then for the TransAm race series where more many more mods were allowed, the Lima engine went fucking mental...
Bashing out 800bhp (allegedly 1000bhp+ wasn't an issue in dyno testing, but of course it needs to last full race distance) from the little 2valve per cyl turbo engine, while still lasting full race distance, these things were mental.
Check out the small water lines from the head next to each exhaust port- Cool little mod to prevent steam/heat pockets in the head, which is one of the many reasons big power turbo engines shit out head gaskets and so on...
Even Ford themselves considered making the engine even better, funnily enough about the same time Ford Europe turned the Pinto in to the YB Cosworth, by creating a twin cam 16V Turbo version. While prototypes were fitted to a few testbed cars, inc a Mk1 Sierra chassis (the B+W pic below), it never saw full production, which is a shame, as potentially it was a Cossie beater when tuned, considering how good the 8V head version is...
Anyhow, after Ford themselves stopped racing it, the tuning scene and indeed the racing scene using these engines went from strength to strength, especially with US Ford 4cyl tuning gods Esslinger Engineering producing countless parts for them, from stroker kits to lightweight, high flow, and strong as hell, alloy heads and blocks.
It's not like these 8 valve engines are only good with a ton of boost shoved down them either, as they're hugely popular in naturally aspirated form in midget racing (crazy single seat dirt track go-kart things, not small people with large heads), and often push out 375bhp from 2.6ltr versions revving to around 10,000rpm!
In fact Esslinger are so confident in these things, they sell a sealed crate race motor, 2.6ltr, 340bhp, and 9400rpm, that is capable of over 30 races before needing a rebuild- Try that with a Pinto!
So yeah, in my eyes at least, as much as the YB Cosworth is one of my, if not my favourite engine ever, it's a real shame Ford USA and Ford Europe didn't work together on engines, as if the Lima existed over here in place of our Pintos (woo, alternate future theories...), our tuning scene, especially the Ford tuning scene, probably would've been even more full of big power cars, and even earlier than it was...
PROJECT "BIG TURBO ON LITTLE ENGINE"- ALSO, SOME HOLSET-RELATED TECH, AS PEOPLE ASK ME ON A DAILY BASIS...
A good few years ago I built a RB20 (2ltr 24V inline 6 with a stroke shorter than most 1ltr 4cyls) powered R32 Skyline with a Comp-R RS341 turbo from Compressor Racing, which was basically a slightly modified Holset HY35- A 600bhp turbo, but a fucking good one.
I built the R32 purely as everyone liked to say RB20s are shit, don't make power, etc etc, plus the fact everyone thinks a 600bhp turbo won't spool well at all on a 2ltr; especially not on a super short stroke engine like a RB20.
I did it to prove a point really, and I did, making a dyno proven 470bhp on a standard head and cams, making some boost below 3k, full boost by 4k, and making big power to 8k+. The mapper said with mild cams and more boost, 550bhp was highly likely even on pump fuel. The thing was a fucking weapon and reliable too, in fact it's still running the same engine and turbo to this day, about 4 years later. There's a couple of pics below, and a fair few vids on my YouTube channel...
Anyhow, a big kickstart to the R32 project was the fact that Chris who owns Compressor Racing offered me the RS341 as a test/development turbo, for next to nothing (in turbo terms anyhow, a couple hundred quid), to prove what the turbo could do, and it's fair to say I jumped at the chance and proved it nicely.
Fast forward to now, and one of my current projects is a Renault 5 GT Turbo Raider.
I fucking love them, they were my 1st n 2nd cars when I passed my driving test, and despite all the mental cars I've owned, they're still one of my fave cars as they're mad fun.
For the last year or so I've been helping a mate spec/build his one, and the result is fucking awesome. 230bhp, revving to 7.5k, totally reliable on standard internals, and as it weighs nothing it's plenty faster than stuff like E46 M3s etc etc.
But the main thing I like about them is the driving experience- Being a tiny light thing it feels 10 times faster and more fun than similar performance in a 'normal' car, and that's why I do cars- TO BE FUN TO DRIVE.
Anyhow, despite shit tuners and retarded owners over the years giving them a bad rep for being unreliable, in reality the GTT C1J engines are strong as fuck when done right. Honestly. I promise! So the other week, despite having a totally different plan until then, I decided it's time to fit a man size turbo to one.
I happened to have a pretty big spec GTT engine sitting in the shed waiting to be used, and like history repeating itself, Compressor Racing just brought out another new turbo, a Holset HX32 based turbo, which ticked the box as ideal for the big turbo I wanted (it's about Garrett GT30 size- 500bhp max).
This time it was me making him an offer, and we agreed, considering all the good exposure my RS341 exploits got him, that I'd buy a turbo off him for a good price in exchange for a no-bullshit writeup on what I'm doing, plus some fitting/tuning info on Holset stuff in general (I get asked on an almost daily basis stuff on Holsets on tuned cars, I seem to have ended up with some kind of 'Holset guru' rep), so here it is...
The turbo in question is THIS thing, their version of one of the 'Holy Grail' (ie fucking impossible to get) Holsets, a HX32. A HX32 is, basically, a HX35 sized compressor mated to a HX30 turbine wheel, which makes for a 400-500bhp capable turbo that spools like fuck, and is very highly rated by all of the lucky few that have got to use them.
They come in a variety of specs, but what got me deciding I was gonna use one on my GTT is the fact this one has a 7cm (about A/R 0.50) T2 (T25, T28, whatever) turbine housing, which, in my experienced guestimation, I think won't spool up much/any worse than the 0.63 A/R GT28R on my friends GTT, but a whole shitload more power potential.
Yesterday, the first thing I did once I had it, was do a mock up on my original/standard engine to see what needed doing, and once it's all laid out I'll take this engine out, put the fancy one in, and make some serious boost...
So far so good, fits very nicely, looks fucking mega, and even my elbow/downpipe (from a Cummins engine, and I found it in my shed at home) fits perfectly, despite being 3.5in ID at the far end! Not sure where I'll route the wastegate pipe, but that's no issue.
I'm gonna make a 3in (probably) custom side exit for the thing, but it's a shame it's not a drag car (and we live in a country that rains a lot), or I'd fit this straight out the bonnet, as it fits perfectly, and is fucking mega- An Inconel exhaust from a Cosworth engine Indy Car!
Anyhow, back to the turbo setup- Here it is off the car. Basically I'm gonna be using the standard exhaust manifold (which is very good, 320bhp+ proven), a spacer/adapter to run a Turbosmart external wastegate, then the HX32 turbo, then finally a 2.5-3.5in cast elbow/downpipe which is a straight fit and makes my life easier as I don't have to fab one up from scratch now...
The original plan (until I found the downpipe in the shed!) was to make my own downpipe, as a normal 2.5in V-band setup like you can find on eBay fits just fine. Barely 1mm out all round, but the wonders of v-bands means that's no stopping a seal- I've been about 5mm all round before and no issue sealing. Here's some pics with the 2.5in v-band clamp...
Another thing that I needed to do, and something most people need to do when fitting turbos, but SO many people don't seem to realise they can, is to clock (ie rotate) the housings to suit the application. Almost all turbos you can rotate the housings 360deg to suit the application, and that's exactly what I had to do for the GTT, so to bits it came, a simple v-band type clamp for the turbine, and the typical Holset circlip for the compressor.
Here's the first "Stav's Holset Tech Tip" for you actually- Compressor housing circlips! They are pretty fucking beefy as circlips go, so can be a struggle to remove, and some people find IMPOSSIBLE to refit, with the grips slipping off over and over again, but I've done SO many over the years I can usually do them first time, and here's how...
First up, Molegrips are the tool to use, bigger the better, and ideally with a curved 'mouth' part, lessening the odds of them slipping off. Removal with them is usually pretty easy- Do up the molegrips to as tight as you can possibly fit them, then use the strength of He-Man to squeeze 'em shut, and that's usually enough to remove the circlip.
Refitting it is a bit of a bastard though, but here's how...
Yep, TWO sets of molegrips! Again, get the grips around the circlip as tight as you possibly can, but unless you're Superman there's no way that's enough that when you close them the circlip is compressed enough- Not even close.
Instead, attach a 2nd molegrip tightly to the adjuster, and use that to (carefully!) wind the circlips closed with that (you've got no hope by hand unless you've a massive adjuster knob on yours), and THEN when you close them up, the circlip is fully compressed, and hey presto, job done.
Oh, here's a mini-tip for you too- Keep the bloody plastic dust covers that come on the turbo, don't just bin them- They're fucking mega handy to stop shit getting in your turbo when you're mocking stuff up etc...
The next issue is this turbo is INTERNAL WASTEGATE, and I wanted to run an EXTERNAL WASTEGATE. That's a big problem, right? Well, people seem to think it is, see loads of people go "I want to run that turbo, but I can't as it's internal gate) but it's not, at all, it's sorted in 5min by welding the fucker shut.
Just like pretty much every Holset I've ever seen, the internal wastegate isn't that big, even Compressor Racing state they'd highly recommend external gate if using on a spark ignition engine, and considering the amount of people running Garrett GT2871s and GT30s with internal gates and serious boost creep issues, I wasn't taking the risk of trying it, and an external gate is a better design from a performance point of view anyhow.
So, how do you do it? Well I've seen some people run a solid bar instead of the actuator, locking the wastegate arm shut, but I don't really see the point of that, so I do what 99% of people seem to do- Turn the MIG welder up to full blast, and BZZZZZZZZZZT.
Yep, just make sure the wastegate flap is fully CLOSED (yep, seen some weld it without it being fully shut, then wonder why their turbo's laggy!), and weld the fucker in place.
You could cut/grind the arm down too to make it look prettier, but I've left it for now as might use it as part of a turbo hanger to support the weight of the turbo when fitted.
FINALLY, and another question I'm always asked about HX35s, HY35s, HX32s, HX40s, and everything else (think even HX55s are the same? I forget now), the bloody compressor outlet flange!
Rather than a normal slip-on, it's a fancy v-band on most Holsets, so your options are, find what the fuck fits to it, or the most common solutions of grinding it down a little and using a normal hose on it, or TIG welding your own chosen fitting to it instead.
Both of those solutions are easy enough, but you could make something fit, or indeed fit the proper thing. While the ID of the flange is 2in, it's bigger than a typical 2in v-band, and you need a 2.25in v-band and clamp to fit to it, but they do, nicely.
BUT the ideal thing to do is just buy the right thing like they had from the factory, and that's this...
That's the normal Cummins compressor outlet pipe, same thing fits 99% of Holsets with that v-band outlet. And is a 90deg bend ending in a 3in slip-on hose fitting. Ideal. Part number is as you see on it- 3918685. I think it's about £70 from Cummins mind, so prob cheaper just to mod it as above...!
Oh yeah, here's another thing I'm always asked- Holset oil feed and returns.
Feed is 12x1.5 thread, don't need a restrictor unless you got mental high oil pressure, but use a -3 line rather than bigger.
Return is IMPORTANT! Almost anyone who cries about their Holset smoking has usually fitted some pissy small return. It needs to be like 19mm ID bare MINIMUM, ie huge. Even most so called 'huge -12 fittings' on eBay have ID of about 12mm, so nowhere near enough. Fuck the fancy fittings, a plain, but large bore pipe is all you need.
AND THAT'S IT FOR NOW, I'LL UPDATE ONCE I'VE DONE ENOUGH NEW STUFF, THOUGH MINOR UPDATES WILL BE ON MY INSTAGRAM, HERE.
Hi, I'm Stav...
You may or may not have heard of me, but I've spent the last 15 years working full-time in the tuning scene, and the last decade or so writing for various car magazines.