91 GT H/C/I Questions

[BlackBetty91]

New here, just picked up a 91 GT 5 spd 38k original this summer! Car already has full exhaust, Fenderwall CAI, and 70mm TB. Picked up some Trick Flow wedge heads (RR's, pushrods) and unknown roller cam (from a 347). I will most likely be getting a GT-40 upper/lower intake from the junkyard for $75.

I'm looking for opinions on remaining supporting mods for this H/C/I Combo. I will get the cam specs if necessary. Would I need 24 lb injectors/mass air to match for this combo? 190 or 255 lph fuel pump and adjustable fuel pressure regulator?

 

[90_red_lx]

190 fuel pump will be fine, but a 255 won't hurt. It's return style. Should be a good running combo, a better intake would gain you a little more, but for the price you won't beat it. 24lb'rs and matching maf would be all you want on a n/a 306. My combo with a 100 shot ran fine with 24lb injectors.

 

[BlackBetty91]

Thanks, and this is a stock 302. Looking at dyno tests it looks as if the GT40 should be all I need, but trust me I want the Trick Flow, love the way it looks. Keep the opinions coming.

Since I'm on a budget i really wanted to leave the injectors/fuel pump alone but sounds like I need to do it right the first time

 

[wesessiah]

the explorer upper and lower intake is still king of the bottom end (with the exception of the performer rpm II) while doing pretty decent all around. if you put a little work into it (especially the lower) it's a pretty good intake setup.

 

[90_red_lx]

You need the injectors and pump. I mean it could EEK by with the stockers, but those injectors will be at near 100% duty cycle which isn't good. I'm not knocking the intake, it will still make good power, especially down low as stated above. Just you can get more out of it with a TFS or eddy.

 

[BlackBetty91]

Thanks, ill need to check to cam specs to make sure it has the right PTV clearance as well. What does everyone think about an adjustable fuel pressure regulator?

 

[BlackBetty91]

Bump, Set on 24 or 30lb injectors and a matching Mass Air.. would 155lph fuel pump be enough for this combo?

And is anyone running Walbro fuel pump? Saw Granatelli and Holley as well

 

[blownfox]

I would go with 30's, matching Pro-M meter, and a 255 Walbro fuel pump.

 

[BlackBetty91]

Will it run alright without a tune with 30lbs?

 

[90_red_lx]

Yes. It will run a little rich though, but it's safe. Run ideal? No. I ran my car for 3+ years of HARD miles, and she was still ticking when I ripped it back down to the shell.

It will put a smile on your face though the first time you hit that loud pedal.

 

[BlackBetty91]

Yep definately ready for that! Anyways arent 24's enough for this? just kinda confused between if i want to get 24s or 30s

 

[trendkilllx]

24lb or 30lb injectors would work fine. I like the Pro m Mafs. I run a 75mm on my car with 24lbers. The explorer intake is a great all around intake. The lower is the bottle neck on it. You can port it or send it to Tmoss to port it and pick up some good power. You should be fine with the stock regulator. I would also get a tune. Its not mandatory unless you have drivability issues like rolling idle, stalling, etc, but there is power to be picked up there. I use a Moates chip with Binary Editor as there are no tuners in my area.

 

[BlackBetty91]

Thanks. I was wondering which MAF to go with, It's between Pro-M, Granatelli, and BBK.

How much work does the lower of the explorer need? Port matched to the TF heads or?

 

[trendkilllx]

I had mine ported to fit my heads AFR 165's which I think uses the same intake gasket as the Trickflow 170cc heads. On mine the hole port looked larger but It looked like he removed most of the material off the top of the runners. Here is a write up the guy that ported mine did.

EECTuning.org • View topic - Intake Porting Guide

 

[wesessiah]

I didnt check out the link above, but you want to index the lower with the head, not just gasket match like a lot of people do. You can put the lower to the head and go through the lower and trace the shape and size of the head port to the lower. Mine werent exactly a match made in heaven with alignment of the ports.

 

[trendkilllx]

I didnt check out the link above, but you want to index the lower with the head, not just gasket match like a lot of people do. You can put the lower to the head and go through the lower and trace the shape and size of the head port to the lower. Mine werent exactly a match made in heaven with alignment of the ports.

Yeah without a doubt. I was just mentioning the gasket as a reference to port size of our heads being close. On the explorer intake it looks like the runners bottleneck in the last 2-3" or so, so you really dont have to remove a whole lot of meterial.

 

[PearlWhiteGT]

Stick with Pro-M for the MAF. 24lb injectors will be fine. Hell, I think I might even have a set somewhere in my garage that I pulled off my fox body. A T-Moss ported lower intake with a custom cam & those heads should run pretty damn good if you decide to spend a little extra $$$. I've gone the cheap route before & kicked myself in the ass for it. I've learned to save a little more even if it takes longer & do it right the first time.

 

[BlackBetty91]

Thanks alot guys ill look into the porting and will make sure to stick with pro - m mass air.

I need to figure out if my cam will clear. I'll start a new thread if I dont get many response but here are the numbers carved into the cam: "erson" is carved, and there is 294/340 and 296/355. Also not sure what these other random numbers 7047 and 0907

 

[BlackBetty91]

Also the official part number is M742120. Cam was on a built 347, dont think it was a high revving engine though

 

[BlackBetty91]

bumpp