State side AAN build

[powaw]

Hey guys, I have been talking about wiring with Paul for my project. I am placing the AAN from a 1995 S6 into my 944. While finishing up the last couple of autocross events for the season I am sorting through the wiring and making plans. My AAN has 170k on the clock and I want to go through the engine before I transplant it over the winter. In an autocross event you generally only use the first two gears. 99% of your time will be spent in second. I need a torquey motor that can pull hard from low rpms and breath good through redline where it can remain for several seconds before slowing for the next corner. My target is the 350-400bhp range. I would like to know what internals people are using to support this goal. I also understand that turbo choice will dictate where my usable power will come into play. Is there a package that is making full boost by 2300 rpm that doesn't run out of air by redline? I have a pretty healthy budget but I also have transmission issues to deal with and all the assorted swap details to accomidate. In the end I want a timex motor, can take a beating and keep on ticking, no glass ponies please. I don't want the sun, moon, and the stars, but the sun and moon would be nice. Also how do you feel about mega squirting this package? I have to be able to beat the wifes Z06 corvette I look forward to your reply's.

[Greg_S]

Hiya, full boost by 2300rpm is quite a tall order, especially if you want to keep it until the redline. im sure there will be some neat tricks that could help with it though.

[powaw]

I figured that you guys would say that. So given my target hp what is school of thought on achieving that. I've read that the rods would be getting close to their limit, depending on torque. I think the pistons are okay. Crankshaft is okay? Looks like people go to the 7A exhaust cam. Does this help improve spool up?
I know that it's been asked a million times, because I've read so many posts on it that I cann't keep them straight anymore. What are the latest greatest turbos to consider? I have two stock ones that need rebuilt, but I didn't think stock would be the best choice for my application.

[Jamo]

Full boost by 2300 rpm and 400 bhp? I don't think that is possible on a single turbo setup on the 2.2 I5 engine, hell prove us wrong

To reduce lag you need to use a reverse inlet manifold such as the Wagner product

If you consider the K24 can't do this, closest thing would be a 2871 or Compturbo equivalent but you talking 3k spool.

Maybe a stroker engine and a 2871 could get close to 2500rpm but controlling surge would be a nightmare and it would run out of puff up top.

Dunno a real head scratcher

[Error404]

you could use a mappable progressive nos controller to reduce lag and help you come on boost

[Jamo]

you could use a mappable progressive nos controller to reduce lag and help you come on boost

NOS?

[Error404]

that must be right before that piece of the floor pan falls off! WTF!

[saltinot]

I hate it when the floor pans fall out. Damn Hollywood Overboost.

[93URS4Avant]

.....and he still manages to drive it home and get away from the cops!!! Only in America - I bet Hollywood could build an engine that comes onto boost at 2500RMP!!!! It would be bigger andf badder and faster and red!!!
They could call it - Audi - a US company!! (See U971!!!)

time for a cup of tea............

[S2central.net]

For 1st & 2nd gear use on 'autocross' - not really territory for a turbo... I'd say small block V8 would be more suitable - heaps of torque without lag. Or maybe a 2.5 stroker with a supercharger - has anyone done that yet ?

[powaw]

I had thought about supercharging, but I am partial to turbo vehicles. We have two others already. As far as NOS I have seen that discussed before but I don't believe that it is allowed by the rules. We have several turbo cars running now that are just killing the lap times. I spend most of my time above 3k during a run. I just want to have the best spool possible. So what do you guys think as far as the engine internals? I need to start searching suppliers.

[S2central.net]

internals aren't a worry unless targetting silly torque levels (above 550Nm) - from a reliability point of view that is...

However in the goal of a zippy revving engine - forged pistons and rods along with a lightened/balance crank and single mass flywheel will make you rev so much easier. Stay away from 7A inlet cam as that is only good at the top of the rev range. The AAN/ABY inlet cam is better for mid range. This will all help bring on boost as early as possible - so will a stiffer wastegate spring - suitable mapped of course, but to minimise lag in a racing application that would make sense.

Get expert advice about a roller bearing turbo from Garrett or Comp - GT or CT - GT2871R could be great, but a similar sized CT might be better. Either way surge could be a problem (as Jamo says) with trying to build too much boost from low revs.

[S2central.net]

Gotta say the more I think about a 944-S2 project, the more this has serious appeal for sheer fun - if not perhaps the ultimate traction afforded by a quattro drivetrain - it would be fun to have the 20VT howl whilst looking out the side windows all the time - LOL. The 944 is actually my favourite Porker - something about the '911' never appealed to me.

[powaw]

If you have never driven one they are very pleasing to have in the corners. While my transaxle can't cope with monster torque I should like as much as it can handle for acceleration out of corners. It's my understanding that they are dealing with 400ftlbs(540nm) from small block chevy motors so I guess that the stock internals should suffice as long as they are in good condition. Any idea how many rpms stock internals can take? Purely out of curiousity, but it would be handy to have a 8k redline for this project. Looks like the real key to making the power I'm after is an aftermarket turbo.

[S2central.net]

hydraulic lifters wont let you stretch to 8000 - but your cams are out of puff by then on a small turbo anyway.