HP Estimate for Engine Build 3.12 Turbo
 

Ok everyone I am starting to build up my engine and want to share with the fellow Pelican's my plans for my turbo setup and get feedback on if I have overlooked anything.

Engine Build
- 3.0L SC block and crank, fresh bearings and rebuild
- 3.3L P&C's with offset rod modification
- Rebuild 3.0L SC heads
- 3.0L SC CAM's (was thinking of changing but not sure what would work best)
- ARP Head Studs
- ARP Rod Bolts

Turbo stuff
- 930 Euro intake and Fuel Head Update changing to 3.2 intake
- Powerhaus injector blocks update going fuel injection
- 930 Intercooler (will upgrade after engine break-in)
- Modified GSF headers with T4 Flange
- New Garrett T04E turbo
- 3" dump into Borla
- Wastegate pipe to left exhaust
- Greddy Profec boost controller
- SDS Fuel injection :)

The reason for the T04E is I was originally planning on using the stock 3.0L SC motor and just do a turbo bolt on, after opening the valve covers I was in for the surprise of 4 broken head studs :( hence the engine rebuild for lower compression :) not sure how the TO4E will act with the motor but I am thinking it will be underpowered.

CIS? How much boost? 250-270 hp at 0.7 bar...

You should have no problem getting close to 400hp or more at 14lbs boost with the right turbo.
Your engine is very similar to mine. I have not had mine dyno'ed yet but Henry Schmidt of Supertec
guided me on my 3.12 build and this was his estimate.
Early SC heads have huge intakes and valves, and the longer stroke with the SC rods using the bushings is a good thing.....SC cams also good.
Consider a turbo oil pump, and a little stiffer valve springs and titanium retainers. And a Bosch 44 fuel pump.

Thanks Chappy, I have followed your post and love your fab work to the 914. I was a PO of a yellow 914 back in the day and always wanted to turbo it but a drunk driver total'd the car so I never got to doing it :(

Are you also using a MSD? I have the BTM model and was curious if you did the same.

For now I have the Garrett TO4E which should be good to push 12~14lbs, with the larger divided T4 flange this should help with lag and provide good response.

Todd- If your going down the road of T-4 turbos why dont you consider a PT-67 or maybe a
37R- my pt-67 made good power and it spooled very well. I recomend the .81 hot housing because it spools pretty well and provides pretty nasty top end. Your setup is begging for EFI.
Not to mention I am selling one....

The TO4E would work for low boost and early spool but I believe it would drop off quite a bit up top. I think you would be leaving a lot of horsepower on the table, but i am no expert on this.
I purchased the MSD BTM for use on my stock SC engine that i turboed running 8lbs. of boost.
I wont use the retard now unless i run into some low octane gas or see sustained boost on the track.

Agree that the turbo will probably be undered powered, problem is I purchased this some time back when I was just planning on using the high compression 3.0L motor, now with the rebuild I am not limited to low boost. My GSF headers are already welded up for the T4 so if I was to sell off my turbo I would look for the same flange mounting.

930gt-40r
send me a PM on the EFI, I am always open for ideas :)

300

I will let you know HP numbers when my car hits the dyno......
Granted i am not looking to extract ever bit of horsepower i can out of my engine, most of my build was base on the engine being reliable, anything over 300hp in my 914 with short gears is a handful.

I was 251 RWHP at 5 PSI, with a crap wastegate and bad AFR's. I expect I am in the 280 range at the moment. Turbo is a T04B in V trim. It makes power to the redline. It's a good track setup; I try to lay off the boost on the street (sort of). I rebuilt mine also, but kept the 3.0 P&C, the early SC with 8.5:! CR. Also have DC-15 cams.

Chappy, what total advance were you running on the SC engine?

Pat

I dont know, Henry said when he converted it to twin plug that it was frozen. When i was running 5lbs of boost i couldn't wait to add more, 5 just wasn't enough gains for me. Pat if you pushed yours up to 8 you will feel a huge difference, i would if i was you. Let it run a little rich for safety measure .........You have the adjustable WUR and water injection dont you, you should be able to run 8 safely enough.
To have perfect AF/R's flat over the entire range on a street car is not that important to me, I can live with it running a little rich here and there, and changing the oil more often.
If i was racing and was trying to extract everything i could from the engine it would be a different story.

Todd and i both have the 3.3 pistons and cylinders with the Euro fuel head, 930 intake and the longer stroke rods with the rod bushing modification which make it spin easier. Add the intercooler and 1bar of boost.... we be smoking.........

Pat get that thing up to at least 300 hp its worth the smile it puts on your face.

Agree, 300~400HP is a nice range to be in, considering my body conversion is all fiberglass, cab components removed, RS door panels I am running on the light side for weight so this should make for a lot of fun :)

Pat
How is is the 915 holding up to your HP? Is shifting a problem and any slipage?

Todd:
The 915 is fine. It never did shift well from 1-2, but it's manageable. Sachs clutch, no rubber center stuff, hooks up OK.

Chappy, I am considering jacking the boost a bit. That should solve the over-rich condition!
Pat

Pat, Thad Suter has run his SC engine at 8lbs for the last 10 years, all he has is the 7th injector for enrichment, no intercooler no fuel head mod, no adjustable WUR. Granted he is not racing his car but his stock SC engine is a testimony of simple fabrication that gets you huge horsepower gains over stock reliably. Add an intercooler and water injection as a safety measure you should be good.

His is not perfect science, with flat AF/R's perfect metering and then-some, but those looking to get gains and not perfection, and can be satisfied with an additional 100hp at the wheels over stock it's a great place to start.

I never had a problem with my engine at 8 lbs. and when we tore it down there was no evidence of any.

Well after further consideration since everything is going to be fresh and I am thinking about selling my 930 intake, CIS, intercooler, MSD and going for a fuel injection monster with a 3.2 intake :)

This will require more work on my part but when doing a complete engine rebuild and having good DIY skillz this will make one bad ass turbo when complete.

Guess I need to start reading some more Megasquirt forums :)

Agree, I could not avoid the fact that Fuel injection would be in the future so I departed with my 930 CIS stuff and now have SDS for my fuel injection needs :) this should make tuning fun..

Why didn't you choose MSII? It's a lot lot cheaper.

I picked up a used SDS for cheap. Only thing missing was the coil packs.