Hello all, currently, im running an 04 cav, m62, 3.0 pulley, gm reflash, cobra h/e/ and pump, full 2.5 exhaust, lsj cia header.

A few questions. The car has been running a TAD funny lately. I do not have a wideband, but narrowband, and its flashing a bit lean. The car still runs fine, pulls hard, but the idle will dip every once in a while. Sometimes (once a month or so) it will chug a bit when I start it up, and then fire. 98% of the time, it fires great.

Im thinking im running into fuel problems. I've still got the stock fuel pump, and the injectors that came with the s/c kit. If I upgraded the pump, and bigger injectors, would I run into a problem with the reflash? Will the car run crappy? what about JUST a walbro pump? Can anyone suggest the easiest pump to install, or a write up?
I'd HATE to lose any boost, but would jumping up to a 3.1 pulley help at all? Ideally, i'd love to run a 2.8, or something very agressive, but dont have the funds to build the engine a bit before doing so.

and sorry for the double post...

I plan to get a new computer over the winter, and have the car dynotuned in the spring. What ACTUAL part (computer) do I need to replace for this? Or should I just wait, install the injectors, fuel pump, THEN go get it tuned with the new computer?

Aftermarket pump will be fine with the reflash (Racetronix W-Body kit recommended), but upgrading the injectors will not. Putting larger pulley on might help a little, but there's no point if you plan on upgrading in the future really. Most you can do at this point is add pressure across the board with an AFPR, and put a methanol kit on it.

A 3.1" pulley is the smallest safe pulley to run on the GM crapflash.

The Racetronix W-body pump is a direct drop in replacement for our cars and wont mess with the GM crapflash. But if you upgrade your injectors you will need to have the car retuned, which means you will need another ECU from another Eco powered J.

You dont need to build the engine for a 2.8" pulley. It isnt going to add 40whp or put a stock eco up to it's failure point. The only things you really need are just larger injectors and a new tune.




its an old concept. time for something new to take the reigns. - Z yaaaa

This racetronix is a direct replacement? I thought I read somewhere, that people were having to grind tabs off, cut this, splice that, etc.

and what about injectors? Should I look into the 42lber's?

There was alittle modification required with using the Racetronix F-body fuel pump, but supposedly the W-body is an easier install.

As for injectors, it all depends on your final HP goal.




its an old concept. time for something new to take the reigns. - Z yaaaa

well, my end goal is going to be 2.8 pulley, and cams. MAYBE meth injection.

I've read that 42's would work for this.

60's to be extra safe. but 42's will get you there. You'll be boarder line on the stock internals with a 2.8 header and exhaust. Throwing cams in there will likely lead to the external connecting rod mod.


1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by: Kronos Performance

WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer

I recommend a wideband first. Also if you upgrade the fuel pump it could make you run richer (which might not be a bad thing).



FU Tuning

sscavalier wrote:well, my end goal is going to be 2.8 pulley, and cams. MAYBE meth injection.

I've read that 42's would work for this.

Remember valvesprings are needed with aftermarket cams. In the end, with a good tune(not the crapflash), i would say you would be around ~240-250whp and that is perfectly fine on a stock L61.




its an old concept. time for something new to take the reigns. - Z yaaaa

Thanks a million for you're input everyone!

My list is as follows : get wideband and fuel pump at the same time this week. Spring: get new ecu, injectors, tow to tuning facility.

Also, (screamingformercy) I also thought replacing the pump might richen it up a bit, but i'll wait until the wideband is in first, before doing so. Thanks again!

Make sure the "tuning facility" is knows HPTuners and is familiar with tuning J-bodies. There are a few people on here that have had a shop butcher theiir tune because they were not that familiar with either.



Edited 1 time(s). Last edited Tuesday, November 30, 2010 5:12 PM



its an old concept. time for something new to take the reigns. - Z yaaaa

good point tinkles. Also, why get towed there? Just swap the pcm there after you drive it onto the rollers. Its only 1 connector.


1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by: Kronos Performance

WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer

^He'll have to swap the injectors before going in for the tune, and unless he can get the new ECU set up ahead of time for the correct IC the motor won't run very well (likely not at all) with the new injectors. Plus, he wouldn't want to sit on the rollers for a minimim of ten minutes for the BCM relearn.

Leafy has a point, I drove my cav with racetronix, 42 lber's and an LS1 tb n full exhaust with a 3.0 on the reflash about 25 miles to my dyno place to have Ryan tune, and It just ran very rich but the gm tune worked. I wouldn't recomend driving it everywhere like that because under light throttle my afr's were in the high 10's but it got me there without a tow.

Good point. Forgot that. You could still always show up early and do it in the parking lot if your tuner would allow that. injectors should only take a 12mm socket, needle nose pliers, and 15-20 minutes.


1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by: Kronos Performance

WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer

I think thats what im going to do. I'll just put the pump in for now, then when I get the injectors and ecu, i'll toss the injectors in, drive to the facility(its about 7 miles from me and called C&S motorsports in Omaha) I've already spoke with them, and apparently they are pretty good with hptuners..I believe they've done a few local cavaliers, or sunfires as well.



Now, I have two more questions. Can someone show me exactly what pump, and harness to buy? I'd rather not mess with a harness, but i've heard the stock harness would limit the walbro nearly 20% lower than it "should" perform. Im going with racetronix, but not sure about f body, or w body, or whatever will work best. Im trying to be as frugal as possible as well.

Also, as far as injectors go, is there a how to? Or EXACT injector set that I could order?(42 or 60lbs) I've been reading about people using extensions, and splicing wires, etc. Im not a complete moron, but I just dont want to F something up....

Thanks again everyone

Quote:

Can someone show me exactly what pump, and harness to buy? I'd rather not mess with a harness, but i've heard the stock harness would limit the walbro nearly 20% lower than it "should" perform.

Use this Racetronix Pump, according to racetronix its a direct bolt in/ plug and play pump setup.
Racetronix W body pump link

And if you want to, upgrade to this dedicated power and ground harness to fix this problem if your worried about it.
Harness upgrade link

Personally I'll be buying both together for my fuel upgrades at some point. Love that harness upgrade, makes me smile.

With the 2.8 inch pulley deff. get 60lb injectors. 42's are maxed out with the 2.8, but some people has used them and worked out ok for them. Also more cooling for the 2.8. Im not sure but can an dual pass end plate bolt to your setup? If so you'll be happy with that. If not meth will help out your IAT's alot, and stay cool as a mofo. Yes C&S knows Hp tuners real well and heard nothing but great things about them. Also will you need a shorter belt for the 2.8? I know you don't on the 3 inch but you might need one for the 2.8. Also for your fuel pump question, the main question you asked, I don't know @!#$ about that, sorry.

i wouldn't bother with the 2.8 (maybe it was just us, or location or somthing) but i'm running 60's, meth and a h/e and we couldn't get any timeing to pull from her without getting knock. Went to a 3.0 and made much more power. Cooling mods are $ beter spent imo. Also don't forget, hi boost pressures mean nothing, its flow that counts

Gary Frank wrote:i wouldn't bother with the 2.8 (maybe it was just us, or location or somthing) but i'm running 60's, meth and a h/e and we couldn't get any timeing to pull from her without getting knock. Went to a 3.0 and made much more power. Cooling mods are $ beter spent imo. Also don't forget, hi boost pressures mean nothing, its flow that counts

x2


I also have the W body pump from racetronix and it is indeed a direct drop in



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