964 Engine rebuild questions

[preston_brown]

BTW the 3.9 liter motor just made 312 HP at the wheels on a Dynojet, which is probably around 360 or 370 at the flywheel. I had plenty of headroom on the injectors duty cycle at the top end with the 0 280 155 831 injectors. But I do run my fuel pressure at 5 bar... so they are flowing 387.3 cc/min or 36.85 lb/hr according to the calculator here:

RC Fuel Injection

The calculator showed that for a 400 flywheel HP motor I'd need injectors flowing at least 340 cc/min @5 bar, so I knew I'd have room to spare.

[ALEX P]

Well I got my car out of hibernation the other week after a couple of months off.



Fitted a Bosch 044 motorsport fuel pump as part of my winter jobs. I had to modify the belly pan so need to finish that off along with my big fuel tank project. It's not actually as extreme as it looks in the photo so will weld a couple of side plates onto the modded section and extend the front.



Managed to get the car back up to the dyno last week for a remap. I fitted the Bosch 0 280 150 792 (E36 M3) injectors and the car gained a bit from last time - It's a bit of a shame I can't say if it's the injectors or the exhaust that made the difference but I am just very happy I didn't go backwards! The scan below isn't the best quality so the before and after results were:

Before: 290.9 Hp @ 5912 rpm with 274.8 lbs @ 5262 rpm

After: 314.7 Hp @ 6234 rpm with 292.3 lbs @ 4748 rpm

Felt great on the drive home

[safe]

Originally Posted by ALEX P

Well I got my car out of hibernation the other week after a couple of months off.

Before: 290.9 Hp @ 5912 rpm with 274.8 lbs @ 5262 rpm

After: 314.7 Hp @ 6234 rpm with 292.3 lbs @ 4748 rpm

Thats good, you must be pleased with that!

So basicly thats:
* RS-intake valves
* DC21 cams
* bigger injectors
* 993 headers and custom muffler
* re-map.
* MAF-kit (?)

If so, thats good numbers for quite small modifications.

[ALEX P]

Originally Posted by safe

Thats good, you must be pleased with that!

So basicly thats:
* RS-intake valves
* DC21 cams
* bigger injectors
* 993 headers and custom muffler
* re-map.
* MAF-kit (?)

If so, thats good numbers for quite small modifications.

Yep, very happy with the results. That's pretty much it for the mods other than JE pistons and some windage work on the case and cylinders.

But (almost) as importantly I no longer have to freeze my butt off on journeys