155LPH fuel pump with NOS?

[ShoGuy93]

155LPH fuel pump questions...

Ok i have been shoping around for a new fuel pump for the silver bullet. And If you read my sig i will have a 3.3L and every bolt on mod. I plan on getting the zex kit down the road once i get the tunning issues down with the tweecer. But i was wondering will the 155LPH pump be enough or should i get the 190LPH pump to be safe. But with the 190LPH will I need to get a Fuel pressure regulator? I did a search but i really didn't find much that answered my question... Thanks always guys

 

[Sho-Driver]

155 should be enough for your needs. If you go with a 190lph, I would recommend a different fuel pressure regulator.

What size injectors will you be running?

 

[Yamaha V6]

190 is fine. I ran a 240lph on the stock FPR on my blower SHO. It wasn't perfect, but 505 crank hp isn't bad, and more often than not it fired right up & drove fine (after replacing the firehose injectors with Accels).

A 155lph is a good upgrade for someone with N/A bolt ons, and should be fine for a small shot of NOS. However, if you increase the shot size (and everybody does), you'll be pushing the limits. Since there's basically no downside to running a 190 on a SHO, you can do it once & forget about it.

Just my opinion.

 

[masho95]

I've run the Zex kit on my car with the 190lph pump. I haven't seen any down points to running the 190lph NA around town.

 

[ShoGuy93]

Cool thanks Fred and masho95 for responding. I will be ordering the 190lph then! Thanks again as always!

Side note what injectors would be good for a mild shot of nitrious and every else that i listed?

 

[K-Dawg]

The general concensus now is that the 190 overflows the stock FPR. I'd use an aftermarket FPR on a 91^ SHO with a 190.

 

[AutoSHO]

A 155 LPH pump should be more than enough for your needs. I've seen people running 75+ shots on a stock 112 LPH fuel pump - A 155 flows more than enough to support your fueling needs.

 

[Yamaha V6]

One other thing I'd recommend is cleaning & flow-balancing (or replacing) the injectors.

I agree with the numbers & thoughts of those on the board. My personal experience was I threw a 190lph in my 91 way back when I first got it - no mods, completely stock, no issues, FWIW. As always, YMMV.

 

[RJ-92]

When I bolt my N2O up I will be using a 190Lb/hr pump, A little insurance and piecce of mind are worth it to me. I'll also be using 30Lb injectors though.

 

[SHOtime2511]

89 and 90 SHO's had some kind of electronic fuel regulator that kept the system from haveing too much pressure...i may be mistaken??? but sence yours is a 93 i guess this doesent matter much eh?

 

[MAD MIKE]

****, i run a 75 shot, on a 250,000 mile motor, with p&p intake with BBB, on the stock fuel system, and it runs fine, besides the whole.. spark plug grenading thing

so im sure a 155 would work fine, 190 would be wonderfull

but from what i understand the 190 will require a fpr, something about increased pressure causes the computer to run lean?????

 

[Yamaha V6]

I have all the dyno graphs from my 91 w/ the 190, and it didn't run lean on the stock FPR at 130k miles.

 

[SHOMurph]

Its a good idea to dyno w/air-fuel to make sure you aren't leaning out before you running mucho bottles.

Lotsa of things can cause a lean out. Better safe than sorry.