LT1-LT4 Modifications 1993-97 Gen II Small Block V8

School me on Fuel Systems

Thread Tools
 
Search this Thread
 
Old Sep 14, 2011 | 10:46 PM
  #1  
IronOutlaw's Avatar
Thread Starter
TECH Fanatic
iTrader: (4)
 
Joined: Feb 2008
Posts: 1,443
Likes: 1
From: Athens, GA
Default School me on Fuel Systems

I tried searching but cant get anything to come up. Im sure this info is already out there but Ill ask anyways.

Im planning a 355 with ported heads and a nice cam. Goal is 400-420 rwhp. I MAY or MAY NOT spray the car. If I do a 150 shot would be as big as I go.

Will a Walbro 255 be enough for this? Im sure it will be for NA power but what about with the spray? Also, I know Ill need bigger injectors but Im not sure on the size. And what about the Fuel pressure regulator. Keep it stock or go aftermarket?
Reply
Old Sep 15, 2011 | 04:37 AM
  #2  
stevo9389's Avatar
TECH Enthusiast
 
Joined: Mar 2009
Posts: 680
Likes: 7
From: Clearwater
Default

yes, as long as the pump is not a knockoff AND you can verify the voltage going to the pump is in spec.

here is what i know from observation on two different cars making about 60-70hp less than your goal both jetted for about 150-200rwhp:

on a dry shot with something to boost your fuel pressure you should be fine with the 255 pump. i have watched the same setup work for about 8 years on the same car without fail. was only tested with 30lb injectors and 42lb.

on a wet shot the stock and 42lb injectors were fine but the gss340 walbro was used instead. the additional cost of that pump over the 255 was marginal at the time.
Reply
Old Sep 15, 2011 | 12:57 PM
  #3  
ahritchie's Avatar
TECH Addict
iTrader: (1)
 
Joined: May 2010
Posts: 2,241
Likes: 1
From: Charlotte NC
Default

Hey, I am also in the process of building a 383 with similar HP goals...(420) No nitrous however. It will have 36lb injectors, will the stock fuel pump support this or do I need to step up to a Walbro 255 too?
Reply
Old Sep 15, 2011 | 06:41 PM
  #4  
Lonnies Performance's Avatar
LS1TECH Sponsor
iTrader: (16)
 
Joined: Feb 2007
Posts: 2,662
Likes: 2
From: Pittsburgh, PA
Default

Once you start to surpass 400rwhp, it is a good idea to upgrade your pump.

For the small price, it is much better than leaning the car out & hurting the engine.
Reply




All times are GMT -5. The time now is 08:01 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE