Turbocharging a Euro 3.2 carrera engine

[kamaro]

I'm swapping in a 3.2 Carrera engine (out of a '86 Euro car) into my '76 911S, I just finished starting the car up and it starts/drives great. Now I came into turbocharging it, I got a VEMS ecu to start with, and I got a nice turbo headers, aluminum tubings, and a nice stock 930 intercooler, my goal is to have 300-325 hp engine and be very drivable and reliable. My only concern is the high CR of the Euro engine, will I need a bigger IC than the stock 930 one to keep detonation out? what size of a turbo you recommend for this setup? size?

Thanks for this great community, I've learned a lot and will probably keep learning for the next years to come!

[scottrx7tt]

Ditch the stock intercooler. It would be pretty hard to adapt it to the Carrera intake. Do you have access to e85 fuel? That alone would help suppress detonation. Use a very conservative spark table. You only need 5-7psi of boost to get to your power goals. Your compression ratio isn’t ideal, but more modern engines have way higher compression ratios wth forced induction and are very reliable

[kamaro]

Originally Posted by scottrx7tt

Ditch the stock intercooler. It would be pretty hard to adapt it to the Carrera intake. Do you have access to e85 fuel? That alone would help suppress detonation. Use a very conservative spark table. You only need 5-7psi of boost to get to your power goals. Your compression ratio isn’t ideal, but more modern engines have way higher compression ratios wth forced induction and are very reliable

My plan is to modify the stock IC by relocating the outlet tube to a different location (I can weld TIG), but I still can look into a different IC setup and modify it to my application. Which size/model of a turbo you think would better suites my goals?

[cmcfaul]

The CR for a euro Carrera is approximately 10/1 (may be higher). With single plug I think that is as high as it will go on pump gas. Adding a turbo to that and not detonating will be difficult.

Chris

[scottrx7tt]

Originally Posted by cmcfaul

The CR for a euro Carrera is approximately 10/1 (may be higher). With single plug I think that is as high as it will go on pump gas. Adding a turbo to that and not detonating will be difficult.

Chris

My engine is 9.7:1 and I am running 10lbs of boost from a k27 7200. The key is proper timing. E85 helps also.

[scottrx7tt]

Originally Posted by kamaro

My plan is to modify the stock IC by relocating the outlet tube to a different location (I can weld TIG), but I still can look into a different IC setup and modify it to my application. Which size/model of a turbo you think would better suites my goals?

There are way too many cheap eBay intercoolers that will be easier to modify. I just bought an intercooler that fits a Mitsubishi evo X. It’s a super easy modification. Under $300.

[K24madness]

I second the idea of E85. It LOVES high compression and boost!

Pump gas is tricky on higher compression and boost. I would opt to lower boost slightly 7-8 psi, have good IC and install more aggressive cams with wide LSA. The later will help broaden power band and bleed off dynamic compression. Look at the DC21 cams, GREAT for this application.

[lite75]

+1 on the E85, running it full time.

[Lyle O]

You guys running E85, did you change out all of your fuel lines (hoses) to be compatible? Fittings?

[Raceboy]

For high CR engine you would need turbocharger with well-flowing (=bigger) turbine. Holset HX35 with 12cm2 turbine is easy choice, flows and spools very nicely while being readily available and reasonably priced.
With proper engine control you will have no problem with compression ratio, just keep mixture safe (around lambda 0.8 at boost) and ignition timing safe. Both are easy to do with standalone.

[kamaro]

Originally Posted by Raceboy

For high CR engine you would need turbocharger with well-flowing (=bigger) turbine. Holset HX35 with 12cm2 turbine is easy choice, flows and spools very nicely while being readily available and reasonably priced.
With proper engine control you will have no problem with compression ratio, just keep mixture safe (around lambda 0.8 at boost) and ignition timing safe. Both are easy to do with standalone.

I ordered the VEMS kit to get this project done, so hopefully it will allow me to tailor the fuel/spark to make the engine happy under boost.

Do you think with that turbo I can get the 300 hp goal I'm looking for?

[scottrx7tt]

You will far exceed your goal. You can make 300 with about 3-4bs of boost. If you run e85, you should be able to achieve about 400hp with about 10lbs of boost. If you have a 915 transmission, get ready for an exploding transmission though.

Originally Posted by kamaro

I ordered the VEMS kit to get this project done, so hopefully it will allow me to tailor the fuel/spark to make the engine happy under boost.

Do you think with that turbo I can get the 300 hp goal I'm looking for?

[spuggy]

Originally Posted by scottrx7tt

The key is proper timing.

This.

Add knock control and set the fuel/ignition up properly; might be surprised how few places detonation happens - but it's pretty crucial to detect/control it when it does.

['76 911S 3.0]

Originally Posted by scottrx7tt

There are way too many cheap eBay intercoolers that will be easier to modify. I just bought an intercooler that fits a Mitsubishi evo X. It’s a super easy modification. Under $300.

+1 on the EVO X Intercooler, they fit well with an inlet change.

Here you can see how the inlet is configured for the Evo X:



And here you can see the inlet rotated 90° downwards:

[kamaro]

Thank you so much guys for all the info. I'm just waiting for my VEMS kit to arrive from Raceboy, I already ordered the Evo X intercooler, I will order the turbo soon then I will try to figure out the best pipe routing.

Wish me luck!