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944 T valves in a N/A

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Old 12-09-2005 | 12:27 PM
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Talking 944 T valves in a N/A

Is there any performance to be gained in putting 944 T valves and springs in a N/A head? I realize other areas need to be addressed but in general is this possible and does it make the head flow better? This would remain a N/A motor and cost is not to big of a concern as I will need to rebuild the head anyway. (stripped timing belt) Would I need to be replace the valve seats, or just regrind them? Any help appreciated. Yes I already used search and didn't come up with much info.
Old 12-09-2005 | 01:13 PM
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Might as well have a turbo head put on if you want it, and it will give small if any gains.
You would need to grind the valve seats out quite a bit, as the turbo valves are bigger (I'm sure you know that part).
Old 12-09-2005 | 11:19 PM
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Hardly. Valves are same size,flow are just a couple CFM's different. The turbo has a better exhaust port,might help a bit...but not on stock cams.
Old 12-10-2005 | 09:23 AM
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I thought that the 944 8v head was exactly the same as the 951, except for sodium filled exhaust valves and ceramic exhaust ports? Worth about .oo1 hp.
Old 12-10-2005 | 09:59 AM
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Yes - the 951 flows about the same.
The sodium and ceramic allow you more boost/EGT margins, so that you can, for example, kick the **** out of any NA small block.
Old 12-10-2005 | 10:00 AM
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Originally Posted by Predator
I thought that the 944 8v head was exactly the same as the 951, except for sodium filled exhaust valves and ceramic exhaust ports? Worth about .oo1 hp.
Nope,the intake side is virtually identical (valves are not the same,but same size) ,but the 951 exhaust has a tighter section right after the valve than the 944,slightly limiting reversion and making the overall (average) port diameter about 4mm smaller...improving port velocity.
Old 12-10-2005 | 07:01 PM
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I have some experience with this. On the advice of Jim Pasha, I put a 951 head on a 88 block. Used the tube factory headers. I have only one thing to say about the difference.
......WOW.....
Of all the 944's that I have had, and still own, this is the fastest 8V car I have ever had. It is simply leaps and bounds faster than the other cars.
According to Pasha, putting a 951 head on a 88 block only (higher compression), would make a big difference. I was somewhat unsure if I could notice much difference, but after getting the car together, It was a ton of difference. I later added a K/N airfilter, and a Flow Master muffler. Even better. I then added a MSD coil and Jacobs plug wires, could not really tell much difference. Then added a PowerChips chip, big difference above 3K rpm.
So to answer the question, in my experiecne, putting a 951 head on a 88 block, yes it makes a difference. Not sure if it would make a difference on the 87 and earlier blocks, but it does on the 88
Old 12-10-2005 | 11:04 PM
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cool, figured as much

Last edited by porschefig; 12-11-2005 at 07:11 PM.
Old 12-11-2005 | 06:39 PM
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Does Turbo/NA use the same Cam?
Old 12-11-2005 | 06:45 PM
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Early N/A cam is same as Turbo cam irrc
Old 12-11-2005 | 07:02 PM
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What about late Cams? Seeing as if one cam has more lift/duration I think it would help performance in a Turbo.
Old 12-11-2005 | 07:12 PM
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I think the late cams are different. How? I'm not positive..I'll search it

EDIT: https://rennlist.com/forums/showthre...early+late+cam
Old 12-11-2005 | 07:13 PM
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Late N/A cam has 1* more exhaust lift, and 7* more exhaust duration (or was it 6*?...)
I am running one in my 951. I was told it helps cut turbo lag. Honestly I believe it does, but I made a few changes at once, and am unable to verifiably attribute it to the change in cams.
Old 12-12-2005 | 09:36 AM
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Hugh - If anything gave Todd an improvement,it was the turbo head. Not the valves alone. Said earlier,valves are same size,turbo head has a better shaped exhaust port. My guess is that the turbo exhaust port helps with scavenging,thus giving Todd his increase...
Old 12-12-2005 | 10:02 AM
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Thanks Skunk - Thats what I was trying to sort out.


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