930 turbo questions more power

[RarlyL8]

There are a host of things that can be done to improve the 930 engine. All of the above listings are tried and true. Typically a slow and incremental approach is better than doing it all at once. I have been involved in far to many truely nightmarish scenarios where owners try to do it all at once and get completely screwed by the tuner or mechanic.

I do have to dissagree about the cams. SC cams alone can produce more off-boost torque in a 930 3.3L than in the 3.0L N/A SC engine they came out of. This is the first thing I noticed on my engine, and the dyno told the tale. Cam and ignition timing are HUGE contributors to improved off-boost performance. It's not just the cams but the proper tuning of the system. Just tossing cams in with the same stock settings is not optimal.

I can set you up with a light weight free-flowing muffler. Check out my website for a few options.

[911st]

I suspect changing the cam dose not effect compression enough to change the need to boost. However, it is possible to run higher compression pistons and make the motor more efficient in other areas like ports exhaust (equal lenght) etc and be able to run lower boost for better pre boost power and the same net HP.

I had a 78 and 91 Turbo. I believe Jeff's example of the 91 turbo is and example of the opportunity of changing the muffler. I am suspect of changes in the headers making more HP, it is the wast gate circut design on the headers that bumps boost.

Getting the same peak HP .8 bar and 1 bar could happen as the K27-7200 comes in fast and hard but dose run out of boost around 380fwhp. I had the same thing happen.

If I had another 91T I would get the cat bypass pipe, keep the stock low restriction muffler, mod the WUR to a boost sensing, and put new 2-5 gears from a C2/4. After that I might look at a bigger turbo.

[911st]

Some have reported that when they re-timed the stock cams it added to pre boost power.

I suspect a lot of people miss the opportunity on the ignition side.

[NathanUK]

Brian, what did you find to be the best cam timing settings for different cams on an internally stock 930 engine?

[RarlyL8]

The best cam setting depend on the setup. If you have stock C/R and ported heads with a big turbo then you may want to dial in more torque. Bump the C/R, stock heads, smallish turbo and you point it to the big end. Driving habbits play into it as well. Lots of variables.

[carrera turbo]

checked out your site im gone be ordering the quite stock exit muffler. but first i need to get the carrera back up and going then onto the turbo upgrades.

ed

[RarlyL8]

You won't be dissapointed. Just let me know when you are ready.

[carrera turbo]

while out driving tonight i noticed that when running a hard pull in third gear my boost gauge would max out at 1.0 bar then drop back to .8 around 6k rpm. is this normal

man what a great car to drive. i have really enjoyed this thread im really learning alot.

how many cars put a smile on your face just thinking about them


ed

[carrera turbo]

Hey Am I Lucky Or What At 1:18 Alaska Time Im The Only Person Online? Is This An East Coast Forum Hmmmmmm??

I Feel All Alone Here

[WPOZZZ]

Originally Posted by carrera turbo

Hey Am I Lucky Or What At 1:18 Alaska Time Im The Only Person Online? Is This An East Coast Forum Hmmmmmm??

I Feel All Alone Here

I'm here.

[NathanUK]

Originally Posted by carrera turbo

while out driving tonight i noticed that when running a hard pull in third gear my boost gauge would max out at 1.0 bar then drop back to .8 around 6k rpm. is this normal
ed

Not really, that's quite a variation of boost.

1 of 3 possible things are happening.

1. Your turbo is too small and can't make enough boost to maintain 1bar all the way to the red line.

2. Your wastegate cannot dump enough exhaust gas so the turbo overboosts. This could be bad header design, sticky wastegate or simply the wastegate dump pipe being an obstruction.

3. Possibly your recirculation valve/assembly is wasting boost so you cannot maintain 1bar all the way to the red line.

[carrera turbo]

hey nathan thanks for the info and i should have gotten back to you it ended up being a sticky wast gate but all is better and im working on three other p-cars and mine is just sitting idle.

can anyone tell me what kind of up grade in performance a set of s/c heat exchangers and one of RarlyL8's quite muffler would yield. im not going to have the funds to go headers at this point as im trying to juggle money between three cars. would like to see 300 H.P. i have the 3.0 heat exchangers from a 78s/c here in my garage is the main reason i would like to run them.


thanks guys this forum has been great.

thanks ed

[RarlyL8]

What heat exchangers do you have currently?

A free flowing muffler is good for ~12HP when compared to a stock Euro muffler on a 300HP engine.
That doesn't sound like much but as others can attest, it is only the beginning. The engine is uncorked. It revs quicker, spools faster and makes noises that will have you laughing like a little girl. It simply transforms the experience.

You want 300HP? That is easy. Stock Euro heat exchangers, K27 turbo, intercooler upgrade, stock boost and a free flowing muffler will pop you over 300HP at the rear wheels.

Want to loose over 1000rpm of turbo lag over the 3LDZ? Bolt on a K27S.

Here is a picture of a Euro exhaust. You will note the similarity of the heat exchangers to those of the Carrera and SC. They are the same.

[carrera turbo]

Originally Posted by RarlyL8

What heat exchangers do you have currently?

A free flowing muffler is good for ~12HP when compared to a stock Euro muffler on a 300HP engine.
That doesn't sound like much but as others can attest, it is only the beginning. The engine is uncorked. It revs quicker, spools faster and makes noises that will have you laughing like a little girl. It simply transforms the experience.

You want 300HP? That is easy. Stock Euro heat exchangers, K27 turbo, intercooler upgrade, stock boost and a free flowing muffler will pop you over 300HP at the rear wheels.

Want to loose over 1000rpm of turbo lag over the 3LDZ? Bolt on a K27S.

Here is a picture of a Euro exhaust. You will note the similarity of the heat exchangers to those of the Carrera and SC. They are the same.

i currently have thermo reactors that the PO out on the car to make it emission compliance. im wanting to put on the sc heat exchangers i have one of your left side exit quite mufflers. and the k27 intercooler up grade then start playing with suspension.

thanks for the pic that looks like what i have.

im looking forward to a little noiser car. but not to noisey



thanks ed

[h20cooled7]

Brian sell him a Zork!

[RarlyL8]

Yes the fun tube is a circus on wheels, but it IS noisy! Ha!

[Miguel Antonett]

The regular Rarly8 exhaust/muffler with the small can is a good option. Good quality and excellent sound - just right!

[carrera turbo]

it will get a rarlyl8 small can for sure as i found some youtube sites with a sound clip and it is a thing of beauty

thanks guys for all the help.

now for the next question with our ambiant temps never over 75 deg. with a rare 80 deg. can i get away with the stock intercooler and the k27 with the s/c exchangers and the rarlyl8 small can?

cheers ed

[RarlyL8]

Yes, as long as you run stock boost.
Turbos LOVE the cold air. The whole deal is keeping inlet temps down. Heat cost power and leads to detonation. I actually have to block off part of my tail in the "winter" to keep the engine operating temps where they need to be. Summer is a whole different ballgame ...
Shoot me an e-mail and we can talk K27 if you like.

[carrera turbo]

thanks for the reply brian,

ill be getting in touch with you before this winter up here is over, on turbo and muffler.

how about air filters or intake is there any reason to get away from stock?

besides it looks like it would free up some space.

thanks ed