JET951

Another project on the go. I cut up a S2 inlet and welded on a base plate and some trumpets. its not complete. Yet to make the plenum.
Sean

Paulyy

very nice sean.
Did you make or buy the trumpets?

I've been thinking of making my own intake on my 951 (after i put it together obviously) and dyno before and after runs on the same day to see if any gains or losses.

333pg333

I love your sneaky projects. Interested to see what you come up for the plenum...

Thom

Nice... What is the runner diameter on the S2 manifold?

JET951

Trumpets bought locally, they are pretty cheap actually, considering if i were to make them on a lathe it would lake quite a while.

i plan to make the plenum from albino sloth fur... Known for its slow response (allows air charge to cool in the chamber)

The S2 manifolds runner is 48mm at the point where it has been cut. its is quite oval where the head meets the inlet manifold

333pg333

Ah yes, of course. Nice choice.

Dubai944

Will be very interested in the results. I am looking at doing the same thing. I have a spare S2 manifold on the bench about to be cut up, but have been wondering if I should use my 968 manifold instead for the bigger runner diameter. If you get good results maybe I can send you mine down to do

What did you base your runner length on, are you trying to tune for a certain rpm range or is it mainly just physical fit?

Paulyy

If i do mine, i'd probably make trumpets. As i'll get some highspeed steel and make a cutter to cut the round edges. or buy trumpets. depends though. I can't wait to see how it turns out!

reno808

Nice. good luck. cant wait to see the results

blade7

Nice, are you going to move the injectors to the plenum to spray into the bellmouths or even run 8 injectors like the RS500 cossies.

refresh951

Thanks for sharing. I have been thinking about this a good bit. Corleone built a similar intake (but for 8V IIRC). Looking forward to seeing the final design and results.

JET951

Physical fit certainly has a big impact on design, but i did want the runners longer then the usual aftermarket intakes like the Speed Force Racing design. The SFR version does not have trumpets either. I have found that for the average 951 driver torque and a large power band helps more then just peak power.

Nope, for now the injectors stay in their stock location. To place the injectors near the top of the trumpets would mean placing them inside the intake manifold or making a complex plenum.

Its going to be interesting as our current 951 has a 3.0ltr 16 v turbo engine with the SFR inlet manifold, i will be doing back to back dynos between the SFR version and our own. hopefully with beneficial results.

Design wise, i am turn between making a large plenum, think as big as the size original unit and have the intercooler work in the stock form. Or make a tube like plenum and have the intercooler Pipes reversed. The benefit is that it would free up more room on top of the turbo, but the intake is that easy to remove so its not really an issue.

The way i look at it is that for me to make them as good as these trumpets i would start off with a solid AL bar in the lathe, probably spent close to 2 hours per piece cutting them down/ shaping and boring them, and they have to be equal. For what they cost from the manufacturer i would be wasting work time.

Thanks Reno, when its done i will be sure to post the results. The only issue is comparison, as i will be comparing our new manifold against the SFR design. As you know there is no stock 16v inlet i can compare with. I may make a 8v version and do a back to back comparison against stock. I am also making one for a customer with an NA 2.5 944. We hare going to make the plenum removable from the flange so that we can swap out the trumpets to test different sizes and see what gives the most benefit.

Thom

The trumpets you have chosen look big enough to me to suggest you might have issues properly wrapping a plenum around them without touching either the engine/turbo and/or the hood. Btw, have you decided on a plenum volume yet?

You said the SFR intake has no trumpets, but aren't runners' inlets bellmouthed?

Though shorter runners will move the power band to the right, the usable powerband should be reasonably widened/compensated for if choosing a turbo that makes very little backpressure, as the engine will breathe way more freely past 6k rpm. I could be wrong but using a 16V head with a KKK-based turbine does not sound like the best of matches to me. You have brilliantly demonstrated that it works reliably, but I can't help thinking you still have some nicely usable top end power hidden in that 16V set up not making it through the hotside.

JET951

Hi Thom,
There is about 30mm clearance to the hood, The top of the Plenum is inline with the cam cover , even enough to fit a strut brace, and we have plenty of room between the turbo and engine, hence the reason i dummy mounted a spare turbo to our spare S2 engine. So we can make the plenum in place. I am leaning towards 2ltr plenum or there abouts.

Im not really doing this for any more power, i just dont like how the SFR plenum has no trumpets or bellmouths. its just dead flat where the runners meat the plenum chamber. We have a few spare S2 manifolds so it seems like a good idea in my spare time.

You could be completely correct with the KKK being restrictive on the hot side, but i could not bring myself to change it. Im getting 15psi at 3000rpm and it doesnt stop making power until redline. even pumping 1.5bar through it. I love these cars.....

Sean

Dubai944

Huh. Amazing SFR didn't at least bellmouth the runner entries on a thousand buck manifold!

What is the intake length from the valve to the mouth of the trumpets you have at the moment?