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Posted by: Coondog Mar 25 2020, 09:40 PM

Been thinking about this for a while as I am halfway there already. Don’t get me wrong 212 RWHP is nice but there always more on the table to be had and Steve’s 3.2 kicks my ass off the line every time..... It’s his 915 tranny....

-964 cams already installed
-Big bore Throttle Body needed
-98mm piston and cylinders needed
-1 5/8" exhaust already installed
-Custom chip would have to get remapped. Not changing Motronic system and not going duel plug.

Opinions and options please.

Posted by: Steve Mar 25 2020, 10:05 PM

Mine is actually a Euro 3.2 that’s supposed to be 231 hp with stock exhaust . Add Bens 1 5/8 heat exchangers, his muffler and steve Wong chip and a tall first and it definitely wakes the car up. My motor also has well over 200k miles on it and needs to be overhauled. I am also on the fence regarding a 3.4 slip in or machine the case and go to 3.5. Once you twin plug, you mine as well upgrade to a 3.6. Keith’s advice is run it til it dies.

Posted by: mepstein Mar 26 2020, 05:50 AM

I would do it to an engine that needs an overhaul but not to a good running engine. Way too much money for little return.

Posted by: Mark Henry Mar 26 2020, 07:55 AM

Only option to me would be buy another core, build the engine you want and sell the existing running engine.
Buy in would suck but likely cheaper in the long run.

I build 996 engines, LN 3.4 to 3.8 JE piston upgrade, so that's a 400cc increase, a lot of guys expect a big increase in HP and get disappointed when I tell them about 40 HP if they're lucky.

Posted by: mepstein Mar 26 2020, 09:34 AM

Yes. With what you have, 10-20hp would be the increase for all that work and money. What you said is telling. "It’s his 915 tranny...." I have one that is getting rebuilt. It's an early mag case with mechanical speedo and a much shorter final drive. It won't be a highway cruiser but should be fun around town.

Posted by: Steve Mar 26 2020, 10:02 AM

My 915 gearbox is a stock 1986 with 8:31 ring and pinion. Taller gears versus an early 7:31 915
Much nicer not having to shift as much compared to a 914 gear box.

Posted by: IronHillRestorations Mar 26 2020, 01:37 PM

Put low profile 15"s on the back That will give you more jump off the line

Posted by: live free & drive Mar 26 2020, 01:53 PM

Try Sal Carcellers fuel injection/chip mod with MAF. There is a lot to read up on Sal on Pelican beyond the link below too.

He can adjust the chip maps to your 964 cams, Ben's headers, and octane you want to run (also method of oil cooling).

http://forums.pelicanparts.com/porsche-911-technical-forum/889886-sal-carcellers-chip-injector-system-3-2-a.html

you might be looking at 250-260hp

I think the whole thing with custom tune cost ~$2K, probably cheaper than cracking open the case.

I also don't think he will help you if your engine is not running right until you get the basics sorted.

Posted by: mepstein Mar 26 2020, 02:02 PM

Sal has a great system and If I stay motronic, I will buy it. It's ~$2K for his custom MAF, injectors, computer and chip but you still need dyno time to tune it. He sends you updated tune's as you work the engine on the dyno.

The last 5% always costs the most and there's a bit of irony because as you make more power from the engine, the 914 trans becomes more of an issue.

Posted by: porschetub Mar 27 2020, 01:49 PM

I had a MAF conversion on my 2.7 ROW 944 ,you could feel the extra 13hp increase just but the best thing was throttle response without the AFM restriction,the kit came with a cam advance key,custom MAF,DME chip adaptor and custom chip.
With the old DME ECU there is the issue with the boards failing Sal ups the game with rebuilt ecu and improved injectors.
I like the Motronic injection ,simple and easy to sort only issue I ever had was flywheel sensors which can give trouble,I think the OP should consider this system for his engine ,certainly cheaper the increasing displacement as mentioned.

Posted by: Tdskip Mar 27 2020, 06:30 PM

^^^^^^
This

Unless you have a surplus of time and money not sure it is worth it. That said - if you really want to do it then do it and have fun.

Posted by: naro914 Mar 28 2020, 06:40 PM

Or...just do a really good job building a 3.2 and get 325 rwhp out of it. Like in Papa Smurf.. ;-)
Ok, so it’s a twin plug, high compression 110 octane race engine...but still....

Posted by: mepstein Mar 28 2020, 07:02 PM

Greg already has a good running 3.2. It's whether going to 3.4 is worth it.

Peter has been coming down to the shop and helping with engine and trans building. That's where the 300rwhp 3.4 street engine came from. He gave me the formula for the engine but not the money to buy the parts.
@http://www.914world.com/bbs2/index.php?showuser=6073

Posted by: naro914 Mar 28 2020, 07:16 PM

Lol...yeah, there is that!