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Bullshit. Can't find the pics anymore, but I'm reasonably sure that the original Glenwood race monster used the standard intake manifold.

la_strega_nera wrote:Bullshit.

Looking at what they are forced to live with in N/A touring cars and WRC I agree. WRC use 34mm on the low pressure side which is much worse then a 34mm on the high pressure side.
Also, most normal size turbos are around 50mm outside diameter on the compressor, seems to work fine.

and that is 1 hole, 34mm in diameter in front of the turbo... and they make 300 bhp with that and monster torque...

You sure it doesnt use custom intake runners Ben..? And by the way, long time no see..!
Was expecting a hello instead of a bullshit , but hey you could be right, but the way i see it, its a factory standard setup for a n/a 2.5 V6. With the turbo its making alot more air and is being restricted with the standard runners surely..?


Surely mid-range to top end HP would be much better..?

Can anyone here give a HP figure for a boosted 2.5 V6 with the standard runners and plenum..?

But hey dont get me wrong, i'd love to keep plenum and runners as is, but with the power adders i have on, i simply dont want any power robbers!!

How restrictive is the exhaust down stream of the turbo? you'll pick up more power, more quickly, there than you will messing with the intake. If Rich Jemison was making near 300(crank)hp n/a through the stock 2.5l plennum on a 3l, then you should have precisely zero problem feeding 350-400 hp worth of air through it with boost.
Just turn the wick up some more - and look for other places to find power - the 2JZ guys don't fuck with changing intakes till they're making 600+hp

Exhaust is 3" from turbo to muffler, which is a straight through Apexi with a 4" tip.

Fuel presssure regulator has to be changed before i turn it up, its starving the engine of fuel, once it hits over 5000rpm it runs lean and HP drops...

what fuel pump are you running?

GarthW wrote:Exhaust is 3" from turbo to muffler, which is a straight through Apexi with a 4" tip.

Fuel presssure regulator has to be changed before i turn it up, its starving the engine of fuel, once it hits over 5000rpm it runs lean and HP drops...

Sounds impossible, the FPR has a restrictor downstream of the engine and the more you need gas the less goes back to the tank, i.e. if you had a problem with a too small FPR it would run super rich at idle.

I'd check the pump as Ben implies above.

Mats wrote:

GarthW wrote:Exhaust is 3" from turbo to muffler, which is a straight through Apexi with a 4" tip.

Fuel presssure regulator has to be changed before i turn it up, its starving the engine of fuel, once it hits over 5000rpm it runs lean and HP drops...

Sounds impossible, the FPR has a restrictor downstream of the engine and the more you need gas the less goes back to the tank, i.e. if you had a problem with a too small FPR it would run super rich at idle.

I'd check the pump as Ben implies above.

If the FPR isn't a rising rate then it will lean off at the top as you max out the injectors because they're only operating at 27psi differential instead of 40 odd...
a normal 1:1 rate reg will work fine, but alot of guys run higher rates to try to eek out a little more injector head room.

No the FPR isnt a rising rate. Hoping Bosch has a rising rate FPR as a replacement.

And fuel pump is standard still.

first replace the fuel pump... the standard pump is just not good enough. buy a nice big fuel pump like the Bosch motorsport unit.

If hou had a fuelpressure meter in the car you could see the problem. at higher revs the pressure probably drops because the pump can't deliver enough fuel to maintain the pressure.

Back to track..

Mats, what do you think of this design?

looks nice, needs more width outside #1 and #6 though.

GarthW wrote:No the FPR isnt a rising rate. Hoping Bosch has a rising rate FPR as a replacement.

And fuel pump is standard still.

might find a rising rate Bosch FPR on a Saab or Volvo turbo. I'd just get an aftermarket adjustable unit.

la_strega_nera wrote:

GarthW wrote:No the FPR isnt a rising rate. Hoping Bosch has a rising rate FPR as a replacement.

And fuel pump is standard still.

might find a rising rate Bosch FPR on a Saab or Volvo turbo. I'd just get an aftermarket adjustable unit.

Never even heard of non-linear FPRs on OEM solutions, why would you even consider anything like that, useless!
Or is the regular tricking of the stock Alfa injection system?