big turbo help/opinions

[euro_urs4]

ok so im looking to go big turbo in the spring, so i need opinions on what to do, so far i have the 2.2l s4 engine, and i can also get my hands on a 2.5l engine from a euro van my questions is, which one would be better of to tune and what are the benefits of each, im looking to aim for 500whp, so lets say 700 crank range, any turbo experts here that can help me lead in the right path how to go about doing this, is it better to stick with the 2.2l and get all that done with this motor or move to the 2.5l eurovan motor, and so forth, thanks alot

[Smiley]

As you need better rods you may go for a stroker with bigger bore and 95.5-crank diesel block and a 3071 or bigger. Search for stroker an 3071 and you'll get inspired
and, as always - deep pockets..

[Billman]

3071 will be too small for 500 WHP

[A80Avant]

waaaay too small....
i got around 320whp with the 3071 and 99 octane gas.(measured on a GPS unit).

[GazzaG60]

GT35r, SC61, Bullseye do some nice turbos too. many other turbos also. look for a t3 with a stage5 0.63 or maybe an 0.82. there are lots of turbos to fill the middle ground too.

motorwise a bigger engine may help but not essential.

lower compression, good rods, exhaust, inlet, cams maybe, fuel sysstem, ECU, good bolts all round.

good brakes essential.

[S2central.net]

700bhp at the crank is a big ask - but its been done - mostly in Norway or Sweden...

On a 2.5 stroker, something like GT40R is gonna be 600-650 from memory. Been a while since I looked at monster turbos... Going up a size from that might get you there. I have a pretty reliable spreadsheet based tool which can be used to plot the compressor map and give an idea of performance across the rev range... It also sizes for fuel injectors and pump requirements.

SUch a monster is going to need ro rev like crazy too - into 8000-8500rpm like Doug's car. He's at 620ish with a nicely sorted GT30 of some sort on 2226cc.

The size of your wallet is going to be just as important here as the size of your turbo to get into 700bhp territory. Good luck if you are serious !


Paul

[Jamo]

Strokers don't need to rev to make power you can make the power on the standard rev range. 700 crank is easy enough on a stroker with the tall block & a GT42R

Your going to need a good bit of head porting, decent exhaust manifold and 4" downpipe.

[S2central.net]

Fair point on the rev range... Fundmentally the higher capacity won't need to rotate as fast to make the same power as smaller engine on same turbo.

Love the way you say 'easy enough'

Mega EM and zorst is a given... So is mega IC and IM... and multiple dump/bypass valves... and a bigger wastegate probably.

[euro_urs4]

yeah thanks alot for all the info, i guess im aiming for 500whp which i know is alot, but something in that range that is just powerful will due for me , i was running a borg warner s472 turbo on my euro e36 m3 swap for my e30, which was gonna push some nice numbers there but never got the chance to finish it so im gonna sell that project of so that i can finish this audi since im loving the awd, but i see nice benefits between the two, cause i know i have to build the full motor and everything and see that it can be done with both, but i think to save some money and use the engine that i already have then i will do that, but unless you think that the 2.5l motor is that much better then i might go into that path

[euro_urs4]

also how much has it been said through out the threads that the 2.2l motor in the s4 or s2 can hold, before you have to start replacing the rods, pistons etc, (s4 and s2 had the same motor right correct me if im wrong)

[terrybullwon]

700 crank is easy enough on a stroker with the tall block & a GT42R

Your going to need a good bit of head porting, decent exhaust manifold and 4" downpipe.

Exactly

Fair point on the rev range... Fundmentally the higher capacity won't need to rotate as fast to make the same power as smaller engine on same turbo.

Love the way you say 'easy enough'

Mega EM and zorst is a given... So is mega IC and IM... and multiple dump/bypass valves... and a bigger wastegate probably.

Exhaust manifold goes with out saying. Wastegate and a Bov are easy to change as your going to have to change all you pipe work any way.

also how much has it been said through out the threads that the 2.2l motor in the s4 or s2 can hold, before you have to start replacing the rods, pistons etc, (s4 and s2 had the same motor right correct me if im wrong)

Rods, not much after 380hp as the torque loves to bend them.
Pistons have been used to 500hp+
Bearings will need to be replaced as due course.
You will nee to think about fueling as well.

There are a few projects on here that will help you, Jamo's 054 stroker thread is worth a read. Dougs MRC S2 and my S2. Prosty done god dam near as 600 with alot of stock parts Rackeltrim

[vcosmin]

also how much has it been said through out the threads that the 2.2l motor in the s4 or s2 can hold, before you have to start replacing the rods, pistons etc, (s4 and s2 had the same motor right correct me if im wrong)

Afaik there are 2 motors on s2 - first with code 3b, (which had distributor), and second with ABY code, which is very close to AAN from S4 (both with idividual coils, and POS,and no dizzy or how is called). The diference from AAN and ABY, is more about IM, and some other peripheral components, as the S4, had a bigger engine compartiment, and of course much more space. From reading on forums, i say that ABY / AAN engine will take about 400-450hp, on stock bottom end, rod, and components. It depends on tuner, on a large degrree if more or less power cand be made.

[Audi_CQ]

ok so im looking to go big turbo in the spring, so i need opinions on what to do, so far i have the 2.2l s4 engine, and i can also get my hands on a 2.5l engine from a euro van my questions is, which one would be better of to tune and what are the benefits of each, im looking to aim for 500whp, so lets say 700 crank range, any turbo experts here that can help me lead in the right path how to go about doing this, is it better to stick with the 2.2l and get all that done with this motor or move to the 2.5l eurovan motor, and so forth, thanks alot

700hp is a lot of HP. Go for the 2.5 with something like a CompTurbo CT364 or CT367 or similar sized turbo. You need a full rebuild with new rods and pistons, ported head with 7A or custom cams, a good standalone system and a good tuner to map it

[euro_urs4]

thanks for the reply guys, info is great and helping me out alot , im looking into the 2.5l like you said and hopefully with money ill be able to reach my goals with that much hp, i just have another questions are the pistons and rods the same for the 2.5 as for the 2.2l or do they differ alittle bit, since i know a company that already makes rods and pistons for the 2.2l and would like to know if those could work right away for the 2.5l for me,

[vcosmin]

thanks for the reply guys, info is great and helping me out alot , im looking into the 2.5l like you said and hopefully with money ill be able to reach my goals with that much hp, i just have another questions are the pistons and rods the same for the 2.5 as for the 2.2l or do they differ alittle bit, since i know a company that already makes rods and pistons for the 2.2l and would like to know if those could work right away for the 2.5l for me,

There are some combination of crank and engine block, which you could use to increase displacement to 2.4-2.6l. Which will, need diferent rods, or pistons, or both, but best is to search the forum for "stroker kit" or "tdi crank"