3.2L or 3.3 turbo?

[rafikdous]

I am building an RSR replica using a '77 shell. The  car is far from original so I do not care about matching numbers, originality, etc

I planned to put a 3.2L in it out of an '89 car. I now have an option (at extra $$s, approx $15k) to put a 3.3L turbo charged engine also out of an '89

I do not know enough about 3.3L turbos except they were widow makers but I am leaning towards it

Which should I go for? The car has a 915 box at this stage

I know myself, I will finish the car, drive it around for year, get bored then sell it for the next project. So long term ownership is not a concern to me

[P-Kay]

booooost

[OZ930]

Depends which model RSR that you are building.  Pre '74, go for the 3.2,  post '74 go for the 3.3 and build a 934 RSR.

If it were mine, I would build the 934.

 

 

[3legs]

Once you go boost you will never settle for anything else. It's very addictive. Massive lag but that was half the fun  

Boost all the way, however turbos ain't cheap.

[LeeM]

 After driving a bonkers 450hp 3.6 turbo 'Bad Boys' replica as my first taste of turbo boost, all I can say is that it is HIGHLY addictive and you'll think anything less is shit! After you shit yourself from 3rd gear wheelspin, then maniacally laughing thinking you're going to die of course! 

 Do the turbo Raf 👍

[Skidmarks]

8 hours ago, rafikdous said:

I am building an RSR replica using a '77 shell. The  car is far from original so I do not care about matching numbers, originality, etc

I planned to put a 3.2L in it out of an '89 car. I now have an option (at extra $$s, approx $15k) to put a 3.3L turbo charged engine also out of an '89

I do not know enough about 3.3L turbos except they were widow makers but I am leaning towards it

Which should I go for? The car has a 915 box at this stage

I know myself, I will finish the car, drive it around for year, get bored then sell it for the next project. So long term ownership is not a concern to me

934!

[Merv]

The boosted engine sounds more fun Raf.  However, the weak link is the 915 'box and a few full torque starts in first and second gear could lunch the gearbox very quickly.  Given the prices of G50 boxes and the 4-speed Turbo 'boxes, you could buy a spare 915 and strengthen some of its components. Other might know how effective this could be in the end. Most folk seem to suggest the max HP on a 915 is around 300-325 in street use. If you are going to exploit the full capability of the turbo motor the 915 may not cut it and the extra cost of a G50 may be a safe option.

[Uncle]

I'd turbo the 3.2 but thats just me. The key to making the 915 last at least a while will be to keep it as cool as you can. Heat=Case flex. Case Flex=Gearbox with Meth(ing) teeth. You will still kill it but less quickly. Billet side cover etc help but the simple fact is the case will end up flexing with heat and things inside that move will move in a way that they should not move (apart) and things will be less than optimal.  

[Peter M]

6 hours ago, Uncle said:

I'd turbo the 3.2 but thats just me. The key to making the 915 last at least a while will be to keep it as cool as you can. Heat=Case flex. Case Flex=Gearbox with Meth(ing) teeth. You will still kill it but less quickly. Billet side cover etc help but the simple fact is the case will end up flexing with heat and things inside that move will move in a way that they should not move (apart) and things will be less than optimal.  

Good thinking Batman.  The $15k saved over buying the 3.3 turbo engine would buy a very nice turbo setup for the 3.2 with modern turbo and ECU.

 @Pork Chops has recently done a modern turbo setup for his 3.2.

The last of the 915's came with a pump and oil cooler that is said to knock 20 degrees off the gearbox oil temps.

[rafikdous]

After speaking to few people, sadly I am not proceeding with the 3.3 turbo for many reasons, drivability, running costs, gearbox, etc

I will stick with the 3.2 and figure out what I can do with it later

thank you all for the input 

[Mike D'Silva]

On 04/10/2021 at 09:38, rafikdous said:

After speaking to few people, sadly I am not proceeding with the 3.3 turbo for many reasons, drivability, running costs, gearbox, etc

I will stick with the 3.2 and figure out what I can do with it later

thank you all for the input 

I'm gathering parts for my personal 3.2 rebuild. Aiming for 3.5 litres.

I've not built a turbo motor before, let alone converted one, so perhaps when I get bored of the 3.5 a turbo might find its way. I've read a few threads but wasnt able to find one complete enough, for a turbo novice like myself. 

[Merv]

On 04/10/2021 at 09:38, rafikdous said:

After speaking to few people, sadly I am not proceeding with the 3.3 turbo for many reasons, drivability, running costs, gearbox, etc

I will stick with the 3.2 and figure out what I can do with it later

thank you all for the input 

Did you try Carl's  30 second extra HP tip?

[Mike D'Silva]

On 30/09/2021 at 18:36, Peter M said:

 

 @Pork Chops has recently done a modern turbo setup for his 3.2.

 

got a link to this?

[Peter M]

2 minutes ago, Mike D'Silva said:

got a link to this?

I think he only mentioned this in passing on this forum.  He probably posted more about it on Facebook.  Why don't you PM him on Facebook.  I think he would be open to a chat.