Hey everyone I have a 97 trans am that i have been working on for the last couple years. The car has a fully forged 9:1 355 with trick flow heads, comp 224/236 cam, headers, 3" exhaust with cutout, 58mm throttle body, ported intake, egr and a.i.r. removed, vortech s trim pullied to the max (have been told that it should make about 14lbs?)front mount intercooler, mondo bypass, single walbro 255lph with racetronix harness, 60lb injectors, in car fuel pressure guage and wideband and a mail order tune from pcmforless.com. I just finished it hasnt been on the road yet. I just have a few questions before i get it dyno tuned to save me multiple trips. Will the single walbro be enough or should i upgrade before i bring it up? Bryan from pcmforless said he made 600rwhp with a single 255, what about a kenne bell boost a pump if it isnt enough?( just seems easier than dropping the tank again and trying to rig up another walbro, and have heard that needs an aftermarket fuel pressure regulator beacause of increased pressure.) I live in dover delaware the two shops close enough that i would trust tuning this are f body central in baltimore and jds auto repair in PA (bryan herter from pcmforless would be doing the tuning) anyone have experience with? A lot of you guys have similar setups in here are there any other problems you think i might run into before i make the trip to the dyno. thanks a lot - brian

 

You are doing a major build there and it sounds pretty good. Your fuel might not be enough with one pump, although the boost-a-pump will make a difference - that might work with a S-trim and 10# of boost or something. Your regulator will probably work well enough.

No one can tell you for sure, but I bet the common consensus will be to go ahead and try to make a dual pump setup cause you will need it sooner or later anyway, if not sooner. Even Racetronix says 500 hp, and that isnt with a blower.

If you have a wideband, it'll be easy to see if you have enough fuel, and if you mash the gas and it boggs badly you will also know. My car was pretty good with an S-trim, 255, and a booster pump, but with the T-trim that setup wasn't enough. If you don't have a wideband, be careful in tuning your new engine and look for retard and do some plug cuts.

 

Single Walbro and 60# injectors should handle up to 600rwhp. You should eventually upgrade injectors or go to dual pumps down the road.

 

I dont think you will hit 14 psi with an s trim. The IC and TFS heads will do great things for making lots of hp per pound of boost but will also eat up a few psi. I see you hitting 600rw but only making arond 11,12psi.

I have also heard a 255 intank is good for 600rw so I think you should be good there.

 

If you have a wideband why don't you use your PCMforless tune as a base and tune the a/f ratio yourself? I see so many people rush to get a dyno tune only to find out the opti is crapping out or the fuel pump is not enough. Its easy to tune if you do a couple of third gear street pulls from 2000 to 6400. Work the bugs out before you take it to a dyno.

 

i dont have the software to tune it and plus have no idea how 2 do it even if i did

 

PCM for less will ge the car so close you might not even need a tune. I have seen his work it is awesome!!

If you dont have the software I would buy it and learn how to use it. You can use Bryans file as the base and always go back to it if you mess something up/.

 

I still would like to get it to the dyno 2 c how much power it makes.
ok
dual walbros- $100 for the extra pump probly around 50 for the rest of the setup. And doesnt that need an adjustable regulator? theres another 100. plus all the hassle of either taking the tank back down or cutting a hole.

aeromotive- $350. tank sump $?. filter $? fuel lines and fittings $?

kenne bell boost a pump - $200. Whats wrong with it? Its what they sell with all there supercharger kits. (750rwhp gt500). Says theve never had a failure? I found a website where a guy has a racetronix 255 with the boost a pump on a corvette thats supporting 800rwhp.

am i missing something?

 

You can get a procharger inline pump for about $50 in the for sale section and that is a 1 hr install. I see them for sale all the time. That is what I'm using right now.

 

From my experience, I installed a single Walbro 255, and a KB BAP. Still had fuel supply problems. Then I re-plumbed to twin -6an lines. I also fabbed the fuel sending unit for a 2nd Walbro 255. Machined the fuel rails for a remote fuel regulator mod. My opinion... the stock fuel supply lines are highly restrictive to fuel flow and aftermarket pump(s) can experience high pressure head flow loss. I also cut a hole in the rear pan for tank access. I have some pics on photobucket.com. Enter search under my ID. (App... 97ss M6 383 - D1). Hope this helps. B.