tod84944

Hugh,
Sorry your thread went south, but now, back to the business at hand.
Skunk is probley right. I'm sure it has to do with the head itself, and not the valves. The next thing I'm going to play with is the fuel pressure regulator. The 8V and the turbo cars use the 2.5 bar regulator stock. The 16V cars use a 3.0 bar regulator. The reason behind this, Grassroots motosports did a story few yrs back on HP gains on a 944 on a dyno. The bigges gain was with a adjustable FPR. They added about 7psi, so a bar being right at 14psi, a half bar would get the same result.
As far as the 951 head on the N/A block trick, the way I understand it from Jim, it only makes a difference on the 88 blocks due to the higher compression, but........ I'm currently working on getting some early euro pistons, (read 10.6 compression, not 10.2!!!). I purchase "Porsche and 911 World" from the UK. There are several Porsche salvage yards that have ads in there. Being e-mailing back and forth with a couple. I plan on using them in my 84, and putting a 951 head on there also. I think............200HP might.... be capable on one of these engines.

HughA44s

No problem about the thread hi-jack. TODD, I am going after a hot N/A engine but want to use a stock N/A head so thats why I was trying to figure out if I coulds use turbo valves, and if they were any bigger. Sounds like a little head (and cam) work is in order. I have worked a 2 1/2 inch exhaust system that works with MSDS headers and has a cat pipe that can be changed out at will. With the cat, the sound is great and not to loud, and without the cat it is loud. After being on this board for a while. it seems if someone takes the correct systems engineering approach to these motors, there is a bit more available.

Skunk Workz

I got a set of those here...still need them? Taken from a good block,car was dismantled because it's now on it's way to become a monster. 200 is not difficult at all...but then you need to do the same to the intake port as the 951 exhaust port has in the beginning...a 3mm smaller cross-section (than the NA) to get some proper tuning. That alone (done right..you don't want to make a smaller cross-section and lose lots of flow..preferably you'll make the hole smaller and gain some flow at the same time) then you are at 180+ already.

TRWright

tod84944

I have a S2 exhaust that I will be putting on. I will measure tomorrow, but from what I have been told, the 16V exhaust is larger, but bolts on perfect. If so, I will have the flowmaster muffler welded in, the cat gutted, and the small resanotor ( I know I spelled that wrong), will be left on.

Skunk Workz

Eh?

special tool

He is not talking to you.

HughA44s

Todd - word of advice, use the "Delta - Flow" series 40 mufflers for these cars with no cat. Trust me on this!

Skunk Workz

You sure,Jim..?

special tool

Yes - he was talking to me and Lart.

tod84944

Hugh, already there on the 40 series Flow Master!!!!!

lart951

Funny, only ehall's , eyal's, rolex's, skunz's, tool's and mine posts were deleted or edited but retardor's remains the same, and the Fastard is not even a paying member.lol. Talk about fairness.

300guy

for reference:

951 intake valve 109.7g

944 intake valve 107.4g

951 exhaust valve 108.4g

944 exhaust valve 98.8g

300guy

does anyone know the spring rates for the 944 and 951 valve springs?

HughA44s

Thanks 300guy - would like that data too.