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Murphy
03-31-2006, 01:14 PM
first off...if there is a better section for this please move it

Is there any real gain by porting the N/A intake manifold or boring out the TB? I know i should be focusing on my turbo engine but I keep wanting to make my n.a engine into a lil monster first LOL. Ive herd its like pointless on a street engine but i would like somefeedback if anyone has tried it.

Murphy
03-31-2006, 01:38 PM
anyone know the size of the TBI TB?
log cars were 42mm and later turbo cars were 48mm right?

turbovanmanČ
03-31-2006, 07:22 PM
If I remember correctly, its pointless.

inmyshadow
03-31-2006, 08:24 PM
I could see it being worth it....


If you were going MPI N/A. But since the N/A motors are TBI, doesn't seem to be the best or easiest thing to do.

later

super60dodge
03-31-2006, 10:29 PM
If your running the stock cam just smooth the casting up alittle.

Being N/A I would have the head mild to raise the compression. I think this would work more ot your benifit then porting the intake.

Murphy
04-01-2006, 12:12 AM
yeah my main plan...if i do anything to this engine....is to mill the head 0.060....im not sure if i am goin to do that or not but if i do i would probly comvert to MPI at the same time since i have the manifold, wiring harness, computer

Whorse
04-01-2006, 01:02 AM
What did you plan on doing for injectors, and what computer setup are you using? Before my TBI died I was looking into converting it to MPFI and it's not an easy task, and tough to find the right injectors or a calibration that works with T1 injectors.

inmyshadow
04-01-2006, 02:24 AM
I'd think the cali would be pretty easy. Just start of using a FFV cali. Or you can scale back the fuel in a turbo computer. You could even use low impendence 3.0 injectors to help bring down the fuel.

Check DCal, there might be a MPI call there from Mexico.


What did you plan on doing for injectors, and what computer setup are you using? Before my TBI died I was looking into converting it to MPFI and it's not an easy task, and tough to find the right injectors or a calibration that works with T1 injectors.

Murphy
04-01-2006, 04:16 AM
i was just going to use a t1 setup...I have a 1pc manifold with stock injectors and an AFPR, 2.5T1 wiring harness and compuer...i would just do something so that it woundlnt hit 100% WOT

Whorse
04-01-2006, 04:27 AM
You can get the mexican cal for the PFI on Gary Donovans site, but there's no info as to which injectors to use. Aside from that it's custom cal as far as I could find.

Murphy
04-01-2006, 03:47 PM
i would think a turbo cal would work fine as long as you dont hit WOT
the turbo cals work in n/a mode till wot right?and with a AFPRi can adjust the fuel if its too much

Whorse
04-01-2006, 03:59 PM
I am pretty sure that the T1 cal limits boost to about 5psi, and then allows up to 11psi at WOT. The older T1 cals might be a bit different, but I know the Vans work on that sort of principle.

89acclaim
04-01-2006, 04:17 PM
The mexican cal and the FFV can are in the SBEC2 and they are harder to find. You chould use megasquirt for fuel and use your stock computer for spark.

Daniel Merrill

turbovanmanČ
04-03-2006, 04:31 PM
Use the stock turbo cal, and use a resistor of some sort to limit the TPS voltage so the computer never see's WOT

Koreth
04-07-2006, 02:22 AM
Don't the turbo computers have two fuel tables, one for part throttle, one for WOT? Why couldn't one edit the fuel tables to be appropriate for an N/A application using Dcal or one of those tools?

JDAWG
04-07-2006, 09:41 AM
I think you would be ok because even at WOT the map sensor wouldnt see any boost, so it wouldnt add fuel. I dont see why it wouldnt work

JDAWG
04-07-2006, 09:51 AM
Huh, just looked at Donovans site. He says at WOT the turbo computer pulls some timing, so yes a diode would be needed on the TPS.

Whorse
04-09-2006, 02:16 PM
Yeah the TBI cars have some weird quirks about them. I could hear the timing change when I floored it, and with the auto, if I hit WOT it wouldn't shift until it hit 5500 every time, even if I backed off some of the throttle. Maybe my car was just garbage (it was) but it seems like there's a lot left unsaid about converting a TBI to PFI.

TurboJerry
05-14-2006, 03:18 AM
That's funny. I hooked my scanner to my TBI car a long time ago and you could see the timing change. it was 6 to 9 deg at *Heavy* P/T, and about 12 to 16 at WOT. (add 6 deg if the dist is at 12 deg.) You can defanately hear and feel the timing change in the car for sure. Porting the TBI intake will give very little. Maybe 5 hp tops. It's like putting perfume on a pig. A SBEC turbo comp. / wire harness with a 2 piece and no turbo would be the most gain if you can't go turbo for now....... I'm thinking VNT cal since it has a good timing curve.