Turbo sizing for a 3.2

[kamaro]

I got a euro specs 3.2 which I'm willing to turbo'fy, I know the 10.3 CR of a euro 3.2 is not turbo-friendly, so I'm planning to swap in a US set of P/Cs that I have already (used, but very clean and has almost no wear), also I'm planning to use a 1mm base copper gasket to lower the CR even more maybe down to 9/1 or so. I got a great deal from a friend for a GTX3584RS turbo with 0.82 A/R and dual ball bearing. Do you think that turbo will be suitable for my setup?, I'm looking for a daily driven car with 10-12 psi of boost that would come at ~3000 rpm, of course I will use a full-bay inter-cooler to keep the charge cool.

Please let me know what do you think about that setup? Is that a big turbo for my setup?

Thanks,,

[RagingBull]

I am finalizing the turbocharging of my Euro 3.2 Carrera (1987 as well, so I have a soft spot for your project!). I have actually done my bolt-on with the stock 10.3:1 compression ratio pistons and cylinders. I am running 7psi boost intercooled. Todd at Protomotive gave me the chip and it is their Stage 1 Upgrade setup, designed for a Stage 3 eventually. I intend to publish a detailed build article on the forums to help those with similar projects.

I would recommend that you fit 930 3.3L 7.00:1 P&Cs since you are alright with opening the engine. This would be a better bet than using the Carrera P&Cs and a gasket. If you think drive-ability will be a problem, I would suggest the 3.4L 8.5:1 (I think). However, with equal-length headers (recommended) and the Garrett turbo, I do not think drive-ability will be a concern.

The 0.82 A/R is the best all around selection for our cars. Personally, I am using 0.63 A/R with a GT3582R but again, mine is a bolt-on and relatively low psi.

[quattrorunner]

Agreed since opening up anyway get some 3.3 pistons n cylinders.

[kamaro]

Thanks RagingBull for your elaborate answer, your info will definitely help. I thought about getting either a 3.3 or 3.4 P/C set, but I came to a point where I just don't have enough budget to add any more expensive parts, I have been collecting parts for this project for about two years. I'm thinking if a 10.3 C/R would be OK for a 7 psi boost, then 9 CR shouldn't be a problem with 10 psi, especially knowing the fact that I already have the US specs P/C set.

Good luck with your project, please create a post for it and let us see what you are working on.

Originally Posted by RagingBull

I am finalizing the turbocharging of my Euro 3.2 Carrera (1987 as well, so I have a soft spot for your project!). I have actually done my bolt-on with the stock 10.3:1 compression ratio pistons and cylinders. I am running 7psi boost intercooled. Todd at Protomotive gave me the chip and it is their Stage 1 Upgrade setup, designed for a Stage 3 eventually. I intend to publish a detailed build article on the forums to help those with similar projects.

I would recommend that you fit 930 3.3L 7.00:1 P&Cs since you are alright with opening the engine. This would be a better bet than using the Carrera P&Cs and a gasket. If you think drive-ability will be a problem, I would suggest the 3.4L 8.5:1 (I think). However, with equal-length headers (recommended) and the Garrett turbo, I do not think drive-ability will be a concern.

The 0.82 A/R is the best all around selection for our cars. Personally, I am using 0.63 A/R with a GT3582R but again, mine is a bolt-on and relatively low psi.

[RarlyL8]

If you're on a budget you may as well use what you have and see if you can dial it in to work for you. The higher C/R buffers lag from that big turbo. An aggressive timing curve combined with the dual ball bearings will light it off quicker. Lowering the boost level hobbles the turbo but the remaining power band will be useful. If the turbo can't be made to work you can find someone looking to add more power and trade it for a smaller one.

[greglepore]

Originally Posted by RarlyL8

If you're on a budget you may as well use what you have and see if you can dial it in to work for you. The higher C/R buffers lag from that big turbo. An aggressive timing curve combined with the dual ball bearings will light it off quicker. Lowering the boost level hobbles the turbo but the remaining power band will be useful. If the turbo can't be made to work you can find someone looking to add more power and trade it for a smaller one.

I'm running a similar setup with stock 3.2, a protomotive stage 1 kit. No i/c, .5 bar. Have maybe 20k on it and its fine. Really nice as it has the torque of a stock 3.2 with a kick. I am going to add an an ic and add vems (its here, just haven't had the time to dig into it). I have useful boost at around 3k in all gears but first.

I wouldn't open the motor just to lower the cr, once in there you ought to do a complete refresh. If using the 10.3 p/c's I would intercool at .5 bar and be done with it.

[kamaro]

I will be doing a bottom end refresh anyway (already have all the parts needed, plus a set of ARP rod bolts), I got that engine used and PO just did the top end including refreshing the heads but never touched the bottom end which more than likely never been apart, so I'm already in there and I have a spare set of 9.5 CR pistons & cylinders set, I just need to make sure that using a thicker base gasket to lower the CR even more (just to be safer) won't affect anything else, I'm thinking the chain length would be stretched by the same amount, the chain housings, camshaft alignment ..etc.

Originally Posted by RarlyL8

If you're on a budget you may as well use what you have and see if you can dial it in to work for you. The higher C/R buffers lag from that big turbo. An aggressive timing curve combined with the dual ball bearings will light it off quicker. Lowering the boost level hobbles the turbo but the remaining power band will be useful. If the turbo can't be made to work you can find someone looking to add more power and trade it for a smaller one.

[joseucabrera]

Looking for a new or used turbine wheel for my Porsche 930.
Turbo No. 930 123 013 04
Thanks,

[greglepore]

With a full bay I'm not sure you'd need the thick gasket assuming your afrs are good. I think the more basic cr you have the better in most circumstances.

[Fever]

Originally Posted by kamaro

I got a euro specs 3.2 which I'm willing to turbo'fy, I know the 10.3 CR of a euro 3.2 is not turbo-friendly, so I'm planning to swap in a US set of P/Cs that I have already (used, but very clean and has almost no wear), also I'm planning to use a 1mm base copper gasket to lower the CR even more maybe down to 9/1 or so. I got a great deal from a friend for a GTX3584RS turbo with 0.82 A/R and dual ball bearing. Do you think that turbo will be suitable for my setup?, I'm looking for a daily driven car with 10-12 psi of boost that would come at ~3000 rpm, of course I will use a full-bay inter-cooler to keep the charge cool.

Please let me know what do you think about that setup? Is that a big turbo for my setup?

Thanks,,

Did you mean Gtx3582Rs?, if so that will do the trick.
Jay.

[kamaro]

Originally Posted by Fever

Did you mean Gtx3582Rs?, if so that will do the trick.
Jay.

Yes, I meant the 3582RS turbo.

Well, I changed the plan. I will leave the engine alone and install the turbo on it and keep the boost below 7 psi and will only use a 91 octane fuel. I will see if it will work out for me, and if I felt that I have enough power to keep me out of trouble I will just keep it that way. I have decided to go with a Microsquirt ECU with EDIS6 ignition system and crank trigger.

[matthepcat]

As an alternative option, you could go with a comp oil-less 3.0 turbo.

Simplifies the install, as you do not need to tap into your engine oil system.

You can order a turbo in various configurations and sizes to meet your need: https://www.compturbotechnology.com/ctr-oil-less

[Fever]

The issue with those turbos is that they need to be water cooled theu the wt ports.!

[matthepcat]

That is not true.

Plenty of people running them with no oil or water. Including me.

https://www.facebook.com/CompTurboTechnology/videos/475911526604058/

Originally Posted by Fever

The issue with those turbos is that they need to be water cooled theu the wt ports.!

[Fever]

Ok.

[kamaro]

Originally Posted by matthepcat

As an alternative option, you could go with a comp oil-less 3.0 turbo.

Simplifies the install, as you do not need to tap into your engine oil system.

You can order a turbo in various configurations and sizes to meet your need: https://www.compturbotechnology.com/ctr-oil-less

I never had an issue about oiling a turbo, also this is a ball bearing turbo which already doesn't need that much of oil capacity, so oil scavenging wont be issue.

[matthepcat]

Just providing another option if you don't want to deal with all that plumbing and the possible need for a pump.

GTR series turbos are great.

Originally Posted by kamaro

I never had an issue about oiling a turbo, also this is a ball bearing turbo which already doesn't need that much of oil capacity, so oil scavenging wont be issue.

[greglepore]

Originally Posted by kamaro

Yes, I meant the 3582RS turbo.

Well, I changed the plan. I will leave the engine alone and install the turbo on it and keep the boost below 7 psi and will only use a 91 octane fuel. I will see if it will work out for me, and if I felt that I have enough power to keep me out of trouble I will just keep it that way. I have decided to go with a Microsquirt ECU with EDIS6 ignition system and crank trigger.

Good call. Worst case is that you'll want more boost, in which case its no bigger deal to do the p/c's later than it is now. I think you'll be very happy with this setup for street use.