My87Targa

this may sound dumb but did you just drop and older turbo motor in?? or did you use the stock n\a motor??

nathanUK '81 930 G50

I thought the issue with that pic of that IC with the long tubes was that all that air in the long tubes had to be compressed, producing heat and the time it takes to compress = lag.

I'm sure it is better than nothing but will produce more lag, not sure how much though, maybe not much at all.

TurboCarrera3.8

87 Targa, The motor is a factory 77 3ltr turbo. The install consisted of the entire fuel system being swaped out of the turbo to accomodate the high pressure fitting and lines. The oil system has to be modified slightly to handle the return of oil from the turbo charger to the oil tank. The 14 pin electrical plug needs to be rewired. I had custom half shafts made with the 4 bolt, 2 dowel for the hub end and 6 bolt, no dowel at the transmission. The motor itself fits in the hole without modification. The rear motor bolts need to be loosened to remove the airbox. I had the difficult stuff handled by Jeff Gamroth at Rothsport Racing in Portland(503-885-9626). He is a great guy and does perfect work.

My87Targa

see id love to do a turbo set up on my car but dont want to swap a turbo motor in. i like the 3.2

TurboCarrera3.8

My advise would be to stick with a factory setup as opposed to a frankenstien motor.

slownrusty

Nathan – I want to clarify…those tubes are not that long at all….trust me, you want to see long intercooler piping look at modern cars like the Supra or Mitsu Evo…In turbo applications the lag is more directed at the efficiency of the turbo and not the intercooler piping per se.

Heat is not produced by having long tubes or elbows – please abandon this theory. Pressure drop is the result of long tubes or elbows.

I want to again re-emphasize that the intercooler set-up on that car posted above is not at all that bad – why are people saying that? With the tight packaging involved under the hood of a 911 you do not have many options like a front mounted intercooler on a typical car.

I dug up my old formulas and here it is…for say an elbow (90degree) that is 2.25” in dia. (typical) it like adding 6.25” inches of equivalent straight pipe. The formula is (30*D)/12.

For a 45degree elbow the formula is (16*D)/12

Regards - Yasin

My87Targa

the car will get mello cams over the winter when i re build it. then id like to do some fourm of forced induction, be it a turbo or a supercharger.

i like the fact that you can get plain nasty with a turbo but dont like the price of the kits out there and lack knowledge about them. so right now im looking to gather as much info as i can on cars that went from n\a to turbo

Win Rice

My87Targa,

Do a Yahoo/Google search on "Juan Ruiz Porsche" for an example of a nice 88 Carrera Conversion. You could easily do a milder version.

Win

nathanUK '81 930 G50

Hi Yasin,
My theory (no proof) is that the extra air due to the tubing (extra volume) will compress when the turbo spools, this is going to take time and cause lag.
The other thing that will happen is when this air is compressed it will heat up. If it is before the IC then when the air cools in the IC it will shrink and need more air to maintain pressure. If it is after the IC then hot air is going to enter the engine which is not good for power.
Once this is done then it will work great.
But there should be more lag with that setup than without having an IC, have no idea how much. Maybe it would only be 100ths of a second.

My87targa,
Does your car have the G50 ?

My87Targa

ive seen that befor, but ive never found any real info on the build up.

i wabba know what all i need to do to prep my motor, for staters

slownrusty

Nathan - the only thing that makes sense from your post above is that Compressed air heats up - that is correct...I was not able to make heads or tails of what else you were trying to say.

An Air to Air intercooler (high efficiency core - bar and plate, well designed end tanks and good air air flow) will reduce air temp by almost 90F and from some calcs I did the air going into an IC (i.e prior to intercooling) can be easily 110F - probably more in a Porsche because of the high heat soak factor.

If you want some good reading, I suggest this, pretty cheap off Amazon ($19US):


Class is now over!
Yasin

Yasin

nathanUK '81 930 G50

I take your word for it as you have read that book but it does seem strange that it would not cause some lag.
The shorter the exhaust to the turbo the less lag so why not the shorter the run from the turbo to the throttle body for best performance. I find it hard to believe.