Tomas

Hello everyone

Who sell them? I cant find them in Summit Racing? best price? Anyone who had experiance with the upgraded wiring harness for the 340 fuel pump?

Anyone has 340 fuelpump with supercharger? if so what in-line fuel pump are you using with the in-tank fuel pump? That pump who comes with the supercharger kit??

regards

Tomas :jester

XTwinTurbo

I believe you can buy Walbro 340 pump from a few of Corvetteforum's supporters. It should cost about $95-$130, depending on whom you purchase it from.

The wiring harness is simply an adapter to change the connectors of the Vette to that of the Walbro pump. It can be easily made and doesn't do much else. The whole pump install took me about 45 minutes (taking my time) and is simple to do.

I am running a Walbro Hi-flow 340 with my supercharger alone. I had the Vortech booster pump with my stock fuel pump but removed the in-line after the Walbro install. (I wasn't sure if the in-line would restrict fuel flow from the Walbro hi-flow.) Still everything I've read says the Walbro in-tank pump is good for 550 - 600 hp and I'm still a little ways away from maxing that out.

P.S. Get the hi-flow Walbro instead of the regular flow if you are going to run a supercharger. It can handle much higher flow rates for higher fuel pressures and only costs about $10 more than the regular pump.

[Modified by XTwinTurbo, 8:32 AM 2/6/2002]


[Modified by XTwinTurbo, 8:33 AM 2/6/2002]

dexion

xtwinturbo,

Are you running the sc on a stock lt1. Ive looked at your mods and is seems you did nothing to the guts of the engine asside from lowering the compression (how was this done? new pistons or heads?). If so can you share some knowledge with me..I am looking in the future to sc my lt4 and I was not planning to do anything to the motor ie build it for sc untill it needs to be done I don't drive the car much. Therefore I would need to limit boost and make sure I get enough fuel to the motor and watch for detonation. Anything (i see you put 42 lb injectors) else I need to worry about?
dex
tia
i'm planning on running sonoco 94 and adding something to the mix to get me higher..Ie taurline or however its spelled...still researching.



[Modified by dexion, 8:41 AM 2/6/2002]

XTwinTurbo

Dexion,

Sorry I don't have too much detail on what was done to the internals of the motor. I actually bought the car with the S/C mod and the motor had been rebuilt for the supercharger. I did however do the remaining mods listed to keep the car running strong.

If you're planning to do a S/C upgrade on a stock motor you may want to do some homework on the http://www.camaroz28.com website under "forced induction" forum. They've taught me a lot of what I've learned.

As an overview; Mostly a stock LT1 motor can hold about 5 - 6 PSI of boost before you'll need to rebuild it. (And that also means you take it easy on the motor) A LT4 may be different and I would keep at the same if not lower PSI rate.
Even with the low boost you'll still need to make sure that you have enough fuel to the motor. Most people advise that the stock fuel injectors (22lb/hr) are suffient if you raise fuel pressure via a boost sensitive FMU (fuel management unit) and also an upgraded fuel pump or inline pump add-on.
If you are running non-intercooled then also plan on ignition upgrade with a boost sensitive timing retard. (Retard 1-3 degrees per PSI of boost)

For my car, I'm running 42lb injectors as I've decided to go without the FMU control and instead use computer programming to handle fuel and ignition requirements. I'm also striving for 500 rwhp (in the future) so I've got an intercooler sitting on the shelf and waiting for a 10 PSI pulley.

Running high octane, Sunoco 94 is always advisable.

dexion

gotit...learnign learning.
Sooo going with an intercooler wil be nicer on the motor...
got it.
dex

Tomas

Hello XTwinTurbo


Thanks for the reply. I have an L98 with ProCharger. I have had problems with the fuel pressure so now im gonna go for a new pump. I didnt find the walbro at the corvette forum?? I think im also gonna take the procharger fuelpump away and just run with the walbro. Can you please give me the name of the company that you orderd from. also partnumber of the pump and the harness if you have

thank you very much

regards

Tomas :yesnod:

BlueDemon

www.ls1motorsports.com

They sell them.

SPD DMN

Thomas, I haven;t a clue what year your Vette is, but you do not need the harness unless your stock harness has broken down and you think you need additional voltage. The 340 plugs and plays with an LT1 harness and I am sure they work with '89 L98's too. I did not buy the extra harness.

SuperL98

Holley has a dirty little secret.
Their high performance in tank pumps are the walbro pumps.
I bought mine from summit awhile back, and it say's
"Product specs by walbro" on the box.
Walbro also stamped on the pump body.

Summit part #HLY-12-903 $149.95
Holley #12-903 255 liter universal gm
Say it is for camaro, buick turbo v-6, but fits & plugged into my 88 vette.

I'm running 8psi on the supercharger and this pump holds 56psi up to 6000rpm with no problem. Regulator set to 48psi and goes up to 56 under boost.

Advise you change the stock vette inline filter often. Gas quality is so bad I've seen these filters kill my fuel pressure output in only a years use.

I had a link to a long discussion about the Walbro pumps, I'll see if I can find it.

Tomas

Hello SuperL98

Thanks for the little secret. So it is the same 255/80psi pump? Are you just using the holley pump or do you have an in-line pump also? Please email me if you find the discussion about the Walbro pumps. What adjustable fuel regulator do you use??

thanks

regards

Tomas


[Modified by Tomas, 7:06 AM 2/7/2002]

SuperL98

Yes, picture of it and specs @ the holley site (and Walbro was stamped on mine) http://www.holley.com/HiOctn/ProdLin...FP/InTank.html

Never understood the inline pump approach, it's so easy to replace the intank one in the vette. Cooled by the gas in the tank, runs better and last longer, quieter.

These 255ltr pumps have enough pressure and flow without the added pump.
For most of us.

I'm using a TPIS adjustable top on the stock regulator. Vacuum line from the manifold to the regulator increases the max fuel pressure with boost.

Still looking for the site about different walbro pumps that turned me on to the walbro in the holley box. Might have been a 3rdgen camaro, buick, or a maita site.
They had some group purchases going on back when I was looking.

Holley actually got p'd at this guy for posting the info.




[Modified by SuperL98, 6:52 PM 2/7/2002]

TurboVette

Check out http://www.racetronics.com . They have what your asking for and manufacture this kit. It's on sale now for $159.95 including a grounding upgrade kit. I've used their products. They are top quality and plug and play easy. Here's a link to it: http://www.racetronix.com/Racetronix...t-GSS307M.html .
Michael

Guest

I second the Racetronix kit, excellent quality, I got mine off of Ebay at a great price. Had some questions when it came, guy called me immediately to help. Highly recommend it and them.