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Just ran across an old Forum 928 article describing their work on a custom carbon fiber intake manifold which flowed substantially more than the OEM intake.
What ever happened to this company and the founder Phil Threshie?
wow! that's a lot of cash o la. were any of these made and/or sold? what were the reported or actual gains? any photos of what they looked like?
for that cost you could do a lot of other mods....
I've attached the 2002 article I referenced in my original post. It shows some info regarding increased airflow numbers and some initial pictures.
However, there doesn't appear to be any HP/Dyno numbers showing what that increased airflow thru the manifold was able to put down.
I think that notation at the bottom was the most important part.....which never happened.
I'm aware of two of these intake systems:
Mark Anderson's intake had the "plenum leak de jour" from the runners coming loose from the flanges. I think Mark took fiberglass and resin to the track to repair the intake as required.
Joseph Fan's intake was apparently just a display piece. The flanges for the throttle bodies (on the plenums) were literally held on with bondo and fell off when we tired to bolt on the throttle bodies...literally fell off!
All that being said, at least something existed. I'm over 10 years into building a custom intake and still don't have a complete intake (I had a test model, which was cut apart to improve on and build additional intakes from)....much to my dismay.
Semi-retired, as of Feb 1, 2023.
The days of free technical advice are over.
Free consultations will no longer be available.
Will still be in the shop, isolated and exclusively working on project cars, developmental work and products, engines and transmissions.
Have fun with your 928's people!
I bought , from Carl, a 104 mm pistons, 5.0 crank with taylor drilling, and block, greg used the block and I still have the pistons and 5 liter taylor drilled crank just sitting on the shelf....
Did not Carl buy all the stuff from Phil Threshie?
I bought the remainder of stuff he had in a warehouse from a girl named Starr that somehow was associated with him or his investors. I believe I was the 2nd or third buyer and a lot of it was already picked over.
I got some good blocks and heads and a fair amount of junk that we just threw out. Lots of Mustang parts too. Apparently Phil was also trying to develop some Mustang valve train bits at the same time he was playing with his 928.
Their pride n' joy was a high-rev motor that Phil was making with titanium rods and Ross pistons. I was able to trace the rods backwards to their manufacturer, which was Oliver Rods. I have had the rotating assembly on this motor spin balanced, and its ready to assemble. But it just sits here, I never have time within my other engine work to bring this to the front. I have the block, pistons, rods, and crank available for sale as a set if someone wants to play.
Damn, we have the highest order of 928 sensei contributing to this one thread. If you don't know how lucky we are to have this fount of 928 knowledge available to us, then you must be new.
Damn, we have the highest order of 928 sensei contributing to this one thread. If you don't know how lucky we are to have this fount of 928 knowledge available to us, then you must be new.
Sorry to dumb this down, but what did you mean, Rob, when you said that the Carbon Fiber manifold was good for -2 torques? I am guessing that the first torque caused cracking/breaking and that it was torqued additionally beyond that?
Correct- Mark's best dyno result before the carbon intake was 431/444 rwhp/rwtq in October 2002. The first time out with the carbon intake it made 485/438, in June 2003, and eventually made 511/442 in October 2003, though that hp figure is a bit suspect as there's a lot of weird oscillation at the very end of that hp curve. It was likely closer to 505ish rwhp.
So I'm wrong, it was more like 75 hp and -2 torques.
EDIT: WTF is wrong with IB? I can no longer upload jpg files the way I have for 17 frickin' years. I'm starting to hate this place.
Pretty sure we had a Threshie built stroker in the PacNW. It's been so long now that don't recall exactly what happened, my recollection was that it never ran quite right. I think the owner took it to Motorsport SLC to get it going and on tear down they found parts they determined not to be compatible.
03-26-2019, 04:43 PM
What ever happened to 928 Developments?
