Turbocharging a type 4 Options

[Andyrew]

Good results from a GT3076. Seems to me those are wheel numbers, which again is pretty impressive for a T4! You could find similar numbers for the Audi 1.8T guys.

Whats equally impressive is the torque curve. There is no boost spike, its straight linear. I cant tell from that first dyno sheet where the turbo makes max spool but Im going to guess its around 4k

Just for reference the GT3076 is about the same size turbo as whats on my Audi 1.8T for those following my setup, and those are numbers I was expecting to hit myself on a much more advanced motor.

[Andyrew]

I'm missing the correlation between big turbo and low boost? I get low boost, but you presented it as if those two work in tandem.

I read his comment to mean that a smaller turbo, when pushed hard, tends to generate more heat than a larger turbo. I would be building this for track use only, so the logic makes sense to me.

I would think you'd be shooting for the most efficient spot on the turbine and compressor maps to keep heat generation down and pressure drop across the turbine relatively low. This likely equates to a larger turbo than would generally be selected since low rev drive-ability isn't really a concern for a track car.

Correct (IMG:style_emoticons/default/smile.gif)

[Jetsetsurfshop]

Been following this thread intently and want to get back to the heads.
Why do companies like Scat and Pauter have there own performance castings for type 1 and not for us? Isn't there enough of us interested to get some of that love our way?
I dont know this, but does the bug and bus crew like using our engines to make more power? It just seams to me that we have enough customers to make some performance castings, right?

[falcor75]

If I was building a turbo setup for a track car I would do it like this.
Which tracks am I driving and whats the lowest revs I will use on track with the current gear /tire ratios. Lowest RPM will determine usable turbo sizes depending on how much you value boost out of those lowest speed corners.

Take this data to the person thats going to tune the car and get their view on turbo size etc. Critical to use someone with ALOT of experience of different setups. A turbo doesnt care if its boosting an aircooled engine or a watercooled engine.

I for one would choose a broad rpm range with boost over peak hp.
An easy to drive car will yield the most consistant laptimes and let you focus on driving.

Not sure it helps any but hopefully you've thought of this already. (IMG:style_emoticons/default/smile.gif)

[socal1200r]

What about using a supercharger for the forced induction, vice turbos? From reading thru this thread, it seems that you would have the resources to make an SC engine work just as well as a turbo one? I don't know a whole lot about either method of forced induction, but I would think you wouldn't have as much of a heat issue with an SC as you would with a turbo, and the plumbing wouldn't be anywhere near as complicated?

I'm talking about the accessory-belt driven style SC units like those from Paxton or Magnuson, not the Roots-style ones. As long as there's a belt on the car, like for the alternator, one should be able to fab up a belt-drive system to power an SC.

Just thought I'd chime in with another option...

[Andyrew]

Superchargers simply can not make the power of a turbo. However there are many people that are using superchargers to spool the turbo similar to how in the old days people would use nitrous to spool the superchargers.

What some have found is that the supercharger becomes a parasite at higher RPM's to the turbo and they put a flapper that dumps the supercharger pressure once the turbo is outboosting the supercharger. Thats just one way of doing it.


Another is twin charging which is simply running both in the same intake track, which I think is the most commonly found method. If sized correctly it can be very potent. I have been considering it for my setup but I simply dont think I can use the power that that setup will make on my engine... I think I prefer to rev my engine out vs the instant torque. We'll see.

Another common method is multiple turbo's. The theory is that its better for spool, and gives you a similar top end as a medium size turbo with two small turbos. But in practice you will find that most high end tuners go to a single turbo application as its far more simple and has just as much if not more power across the board. I believe its so common among manufacturers today because it is more compact than a large turbo.

Finally there is compound turbos. Not something I would recommend in a racing application but BOY is there some power potential there. Unlike twin turbo's compound turbos have a small turbo that feeds directly into a large turbo, essentially spooling it quickly. The issue with a compound turbo is that you overspool the small turbo. This is very similar in practice to the twin charging setup as you have something that gives power down low as well as spooling an incredibly large turbo.



If hes only looking to make 350hp from a turbo 2.0L that wont be that difficult. As shown by Mike a nicely built T4 can easily do it on pump gas within a safe boost range. Decrease the turbo size a little bit, run race gas and lots of timing and you have a very nice setup for the track. For a track car it'll provide plenty of power in the lower register of his gear infact he might find that the torque it produces is going to be problematic for his transmission..

[HAM Inc]

O.P., can you convert to a T1 engine for your class?

If so find an aluminum Auto Linea case and build from that. There are plenty of new T1 head options out there that are stronger than T4 heads.

[stownsen914]

That's a nice build thread from the shoptalk forum. I haven't finished reading it yet, but definitely will.

As for what I can do for my build, I don't want to limit myself to 350 hp if more is reasonably available (IMG:style_emoticons/default/smile.gif). For trans, I'd switch to a 915 and use custom gearing to get the RPM range where I want.

[Mueller]

Been following this thread intently and want to get back to the heads.
Why do companies like Scat and Pauter have there own performance castings for type 1 and not for us? Isn't there enough of us interested to get some of that love our way?
I dont know this, but does the bug and bus crew like using our engines to make more power? It just seams to me that we have enough customers to make some performance castings, right?

^ditto... even MOFOCO has brand new cast in the USA heads starting in the $300 each range. ( doing some reading I guess they had some iffy quality issues years ago but current heads supposed to be decent for street motors, not designed for race car applications as is)

I think the solution is water cooled heads like the 934(935?) race cars.

[Andyrew]

That's a nice build thread from the shoptalk forum. I haven't finished reading it yet, but definitely will.

As for what I can do for my build, I don't want to limit myself to 350 hp if more is reasonably available (IMG:style_emoticons/default/smile.gif). For trans, I'd switch to a 915 and use custom gearing to get the RPM range where I want.

So your basically looking at about 15-20k engine+trans. Right?





I dont think he can run a T1 at PCA events. It needs to be a "Porsche" motor and trans.

[Mueller]

O.P., can you convert to a T1 engine for your class?

If so find an aluminum Auto Linea case and build from that. There are plenty of new T1 head options out there that are stronger than T4 heads.

Might as well do an LS1 if crossbreeding is allowed (IMG:style_emoticons/default/smile.gif)

I think block needs to be "Porsche" (even if one considers the Type IV a VW motor)

With the block needing to be Porsche even a 924 motor or a Macan motor would be legalish

[HAM Inc]

Technically, the T4 is a VW. It has VW stamped all over it.

It might be a stretch of the rules, but if they say engines must be of the same manufacturer as originally supplied it might work.

[ThePaintedMan]

I think for the amount of engineering involved and the very real possibility that a type 4 with that much boost on it may still be a grenade, I would consider another watercooled Porsche engine, as Mike suggested. What about a turbo 944 motor, or even a 928 V8? Those things can make some pretty healthy and reliable HP numbers without nearly as much $ or time as it would take to make the TiV work. All you need is a radiator and some water lines (IMG:style_emoticons/default/smile.gif)

[HAM Inc]

I think for the amount of engineering involved and the very real possibility that a type 4 with that much boost on it may still be a grenade, I would consider another watercooled Porsche engine, as Mike suggested. What about a turbo 944 motor, or even a 928 V8? Those things can make some pretty healthy and reliable HP numbers without nearly as much $ or time as it would take to make the TiV work. All you need is a radiator and some water lines (IMG:style_emoticons/default/smile.gif)

That makes more sense (to me) than a roadrace turbo T4.

But I'd love to see a well engineered and deep wallet turbo t4 build for a roadrace car. I'd like to see how it went and what tech was developed along the way.

Been plenty of turbo t4 street engines, but they don't see the abuse a track car does.

[Mueller]

I think for the amount of engineering involved and the very real possibility that a type 4 with that much boost on it may still be a grenade, I would consider another watercooled Porsche engine, as Mike suggested. What about a turbo 944 motor, or even a 928 V8? Those things can make some pretty healthy and reliable HP numbers without nearly as much $ or time as it would take to make the TiV work. All you need is a radiator and some water lines (IMG:style_emoticons/default/smile.gif)

I think the Macan 90° V6 would be ideal.

It can be found with super low miles in the $4-5K range (I've been told some places would happily take $2K for one since there is no real market)

It is shorter than a straight 4 like from the 944 and the motor is more or less brand new and won't need an expensive rebuild like the old used 944 motor would need and it would still be cheaper than building a turbo Type IV and should be dead nuts reliable unless those motors have some odd issues that we haven't seen pop up yet.

[Mueller]

I think for the amount of engineering involved and the very real possibility that a type 4 with that much boost on it may still be a grenade, I would consider another watercooled Porsche engine, as Mike suggested. What about a turbo 944 motor, or even a 928 V8? Those things can make some pretty healthy and reliable HP numbers without nearly as much $ or time as it would take to make the TiV work. All you need is a radiator and some water lines (IMG:style_emoticons/default/smile.gif)

That makes more sense (to me) than a roadrace turbo T4.

But I'd love to see a well engineered and deep wallet turbo t4 build for a roadrace car. I'd like to see how it went and what tech was developed along the way.

Been plenty of turbo t4 street engines, but they don't see the abuse a track car does.

Did Jake or you give up on the billet Type IV heads? Too expensive and small of a market I guess?

[HAM Inc]

I think for the amount of engineering involved and the very real possibility that a type 4 with that much boost on it may still be a grenade, I would consider another watercooled Porsche engine, as Mike suggested. What about a turbo 944 motor, or even a 928 V8? Those things can make some pretty healthy and reliable HP numbers without nearly as much $ or time as it would take to make the TiV work. All you need is a radiator and some water lines (IMG:style_emoticons/default/smile.gif)

That makes more sense (to me) than a roadrace turbo T4.

But I'd love to see a well engineered and deep wallet turbo t4 build for a roadrace car. I'd like to see how it went and what tech was developed along the way.

Been plenty of turbo t4 street engines, but they don't see the abuse a track car does.

Did Jake or you give up on the billet Type IV heads? Too expensive and small of a market I guess?

Waaay too small a market for a high-end T4 billet head now. The new AMC castings are very nice and meet the needs of 99% of the marketable T4 applications.

When we were doing that development the economy tanked and demand for high-end T4 engines shrank, but demand for modern Porsche engines took off. We saw the writing on the wall.

The T4 head design - with its exhaust outlets positioned between pushrod tubes - presents some baked in application limitations that are a real challenge to overcome. The most practical way to get around them is to move to a T1 style exhaust arrangment, which the Engine Plus heads did very nicely. They were great heads, but they too suffered the market lmitations facing the T4. Last I heard they were NLA.

If someone wants to build an engine that goes to that level, switching to a T1 based platform makes more sense. Plenty of Hi-Perf parts - from blocks to heads - already developed. Of course much of it is Chinese junk now, making it even crazier to try to develop a T4 configured billet head.

[stownsen914]

On the engine type, it has to be either Porsche block or an engine type that was supplied in a Porsche. So an Audi/924 engine or a T4/914 qualifies, unfortunately T1 doesn't.

There is an option to do non-traditional engines like Cayenne, Macan, 928, 944, etc., but 2 things about that:
1. Switching engine/chassis type puts you into a different class (GTP) that basically no one runs in.
2. Doing a Cayenne, Macan, etc. probably would be even less economical than a T4, and at the moment those engines are not classified for PCA Club Racing. For those engines I'm not aware of off the shelf performance parts like camshafts, intake manifolds, etc. or that anyone has invested in learning how to extract power out of the heads. Breaking new ground sounds like $$$$ to me. If I could use one of those engines, I'd need it to make ~150 hp/L, which is where the modern engines seem to fall on the hp to weight index for PCA club racing.

[HAM Inc]

On the engine type, it has to be either Porsche block or an engine type that was supplied in a Porsche. So an Audi/924 engine or a T4/914 qualifies, unfortunately T1 doesn't.

There is an option to do non-traditional engines like Cayenne, Macan, 928, 944, etc., but 2 things about that:
1. Switching engine/chassis type puts you into a different class (GTP) that basically no one runs in.
2. Doing a Cayenne, Macan, etc. probably would be even less economical than a T4, and at the moment those engines are not classified for PCA Club Racing. For those engines I'm not aware of off the shelf performance parts like camshafts, intake manifolds, etc. or that anyone has invested in learning how to extract power out of the heads. Breaking new ground sounds like $$$$ to me. If I could use one of those engines, I'd need it to make ~150 hp/L, which is where the modern engines seem to fall on the hp to weight index for PCA club racing.

We started massaging Cayenne heads a few years ago. Much potential there.

[Mueller]

Waaay too small a market for a high-end T4 billet head now. The new AMC castings are very nice and meet the needs of 99% of the marketable T4 applications.

When we were doing that development the economy tanked and demand for high-end T4 engines shrank, but demand for modern Porsche engines took off. We saw the writing on the wall.

The T4 head design - with its exhaust outlets positioned between pushrod tubes - presents some baked in application limitations that are a real challenge to overcome. The most practical way to get around them is to move to a T1 style exhaust arrangment, which the Engine Plus heads did very nicely. They were great heads, but they too suffered the market lmitations facing the T4. Last I heard they were NLA.

If someone wants to build an engine that goes to that level, switching to a T1 based platform makes more sense. Plenty of Hi-Perf parts - from blocks to heads - already developed. Of course much of it is Chinese junk now, making it even crazier to try to develop a T4 configured billet head.

Thanks for the reply.

How funny, I did a search for those Engine Plus heads and came across a thread with Jake showing off his billet heads!

http://www.shoptalkforums.com/viewtopic.ph...97&start=30

So if someone was to redesign some heads for their own use you'd recommend going the Type I exhaust route?