Imo000

Those hose clamps on that SHO intake are and exact fit and look (motorcycle style) of the OE early 32V clamps except they are stainless steel. Have a set in my '85 that I pulled of a car at the local junkyard years ago. Ford sells them to but they are around $10ea.

heinrich

......

Mongo

I neglect to understand how adding something more complex to an intake manifold would be even better than what Porsche has done originally. We are trying to get gains from simplifying the manifold, not make it more complex.

mark kibort

making something simple happen, by making it more complex.. makes sense to me!

by the way... what is the throttle body diameter of the S4? what is it on the S3?

Imo000

I thought you were trying to get gain regardless of complexity. Now not only that it must be cheap but also must be simple too? Some design criteria you two have.

Mongo

Incorporating butterflies to 'stage' the intake is complex in my book. Why did Ford and Yamaha do it? To even out the torque curve in a similar way?

Intakes like the LS and that Aston Martin engine do not have any tuning flaps in them (at least the LS does not. I need to see the Aston Martin one again). Those 'simple' intakes yield some pretty good gains. So, why the heck not then?

mark kibort

the difference is the short , larger runners offer more power up high. more peak power.. its what we are looking for, the long runners are for the mid range. porsche did the same thing with the variable runner length design for the 911

Imo000

I'm gong to take an educated guess that besides you (aka we), not many are interested in peak power gains but rather want mid range power increase. A street driven car will benefit alot more from a mid range improvement that near redline.

V2Rocket

s3 = 3"/75-76MM

variable intake vs variable cam timing...
ford didnt have variable cam timing on that engine.

and the LS has all the torque you'd ever need due to the displacement, along with fantastic heads, so they don't need intake witchcraft.

Mongo

Ah, but the Gen IV and V LS engines have VVT now. Yet, they still run a simple manifold.

mark kibort

We, (aka, not you), now know from interaction from this list, is that if you want to accelerate the hardest, meaning with the greatet force, you not only have to be at WOT, but the RPM needs to be high. anyone that does or expects performance in the midrange, at WOT, is not really clearly thinking. the entire low and and midrange torque things has always bugged me. who drives seriously like that?
Plus, with cars like ours and engines that sound like ours, they are meant to be driven from 4500rpm to 6500rpm. thats how they are designed. the the mid range performance thing is part throttle , lazy passing or hill climbing without having to downshift. boring stuff. we are talking performance here! (we, meaning, not you)

mark kibort

really, the S3 is so small? why dont we all get the S4 throttle body increased to something larger too.. if the stock euro 2 valver was 3.3", i would think that the S4 would be more. turns out, no? that could be part of it.

I saw some dyno tests for the 6.4 liter that used the 80mm throttle body and extruded honed intake, and there were little or no gains. this just proved to me that the intake is junk!!!! if a 75mmm throttle body isnt restrictive on a 5 liter, then that intake HAS to go!!

mark kibort

am intake. remembrer, set up for power only. the tweeks with valve timing is more for small changes to mid range. it has the RPM to make up for the lack of optimization in the lower ranges. this is how you make power. big runners!

James Bailey

Mark there is NOTHING unique or SPECIAL about the sound of a 928 V-8 zero zip nada.....it has a standard firing order, no flat plane crank, absolutely nothing out of the ordinary !!!
And the reason why Porsche ended up using a "big" V-8 was so they did not have to spin the engine, getting away from the distracting noise and fury of the little air-cooled flat six.....all by design not an accident or mistake.
There is no reason why an S-4 intake SHOULD work on a stroker engine which does not make it "garbage" simply not what they WANTED.
I get it, you want a race intake but given how few people are racing 928s that is a very limited market.....
You might look into lost foam epoxy molding as a technique to fabricate one off manifolds.....pretty sure that is how the Threshy intakes were formed. If you can shape Styrofoam into the passages you want you then cover it with plastic wrapping tape as mold release protectant and lay epoxy over it, S glass is heat tolerant and far cheaper than carbon fiber......once it sets you pour lacquer thinner into it to dissolve the foam.
It really is that simple Especially with the Salsbury Plenum.

Jim Devine

DIY manifolds and the ultimate plenum, the Flowmaster---
R&D doesn't have to be costly.

http://blog.modernperformance.com/27