my first project finally done, its a blast

[402bigblocks10]

whats up everyone. my name is todd, i live in fl....i have a 89 s10 blazer with a big block, i spent about a year building it. ive always wanted to put a v8 in a blazer, as my first car was a 88 4x4 s15 jimmy, i loved that truck. i would have to say it was the perfect vehicle to choose for a project.... im having some fuel issues and i was wondering if someone can help me out... but anyways im new to this forum thing, so like i said i just wanted to say whats up. im ganna post some pics in a couple day or so...... are there any meet up's in the orlando area?

[racer1182]

you have any pics of it that w can see. glad to hear you are enjoyin it so far. what ind of issues are you havin with it?

Greg

[HardinValleyMagic]

Welcome to site! Yup we like pics and videos! Now about the fuel issues, um what are they? Any questions, throw them out there and there is a real good chance the answer will be found.

[wild572s10]

welcome to site and this group of guys will find the answers and I've learned alot from them and can't wait to see pictures on or in albums

[402bigblocks10]

i just got it painted about 2 weeks ago, so i have to take pics, at about 5000rpm the fuel psi drops to 0. i have a holley blue pump and regulator...carb is a holley 750 dp....

[spacecadet]

Welcome to the site.

What size is your fuel line? Too small? or Maybe theres a kink.

Space

[ZR1BLAZER]

i just got it painted about 2 weeks ago, so i have to take pics, at about 5000rpm the fuel psi drops to 0. i have a holley blue pump and regulator...carb is a holley 750 dp....
did you remove the pump from the tank? if not you could be sucking trash or plugging the line with the sock on the pump. is you pump now dead headed or return?

[402bigblocks10]

i removed the old tank and now have a cell in the back behind the rear seat, the fuel line is -8, about 1/2 in line. no return in system, and im regulating it to 10psi

[ZR1BLAZER]

Voltage drop to pump at high RPM? what amp alt and what other electronics are in the truck?

[402bigblocks10]

i havent checked for v-drop, thats my next thing to check. just a stock alt...other elctronics in truck are ign syst, fans, lights,, starter, just the basics, but all are on their own circuits...

[ZR1BLAZER]

fans and igniton pull some amps. and if you have some high power fans then the amps they are pulling are high. then consider what amp rating your pump is. if your running a 65 amp alt your total amp draw might be to much at high rpm when the ignition and pump work hard and fans are also pulling. they may be on seperate curcits but total draw is still pulled from the alt.

[ZR1BLAZER]

there could also be a restriction some where in the line? but i would see that dropping fuel pressure just at high rpm. it would do it randomly at all rpms? this is a tough one.

[harleyboy]

welcome to the site and it sounds like you have a clean blazer can't wait to see the pics.

[402bigblocks10]

so do you rec a bigger amp alt, or just a hight psi pump

[-Deception-]

Sweet cant wait for some pics.

[ZR1BLAZER]

so do you rec a bigger amp alt, or just a hight psi pump

i would like to here the run down on your combo and why your running 10psi 1st? 10psi and low voltage at top end could be the prob?

[inou2]

I'm with ZR1BLAZER, you should have your fuel psi regulated down to about 7psi. 10 is really on the high side.

[RONSTPIS10]

where do you have your pump located ? do you have a fuel filter in line ? has the pump been sitting for a while? i had one holley that was sitting that most of the vanes were gummed up and it wasnt pumping enough i took it apart to find only one vane moving freely i cleaned them up and it was much better

[402bigblocks10]

zr1blazer-im running a rci cell in that back, down to a holley blue, then to the filter tn to the reg..and the reg is on the firewall about 8 inch from the carb, im running 10psi because thats what people i know told me to run it at... even if i run it down to 7 wont it still do the same thing? the pump sat new in the box for about 8 months before i put in on the truck,

[Melonhead]

Is the fuel line ran anywhere near the exhaust? Heat can cause vapor lock. Running dead head for a street truck is not the best set-up ot helping things. A return line would help the pump cooler and from surging. The thing that would need to be changed is the regulator to a by-pass style. I also agree that 10#s is too much.

[402bigblocks10]

i made sure the fuel line wasnt near any exhuast when i ran it, so i dont think that is an issue.. should i get a better quality reg too or do you think a holley with by pass will be fine? can you explain better why a dead head set up isnt good for the street?

[Melonhead]

Think of this. You cruise or idle most of the time. This requires little fuel. The pump is spinning away all the time and the fuel inside is not moving much. The longer the pump runs, the hotter the pump and fuel gets. When you stomp on it, the fuel surges. It finally has a place to go. With a by-pass set-up, the regulator allow the un used fuel to return to the tank. This allows the fuel to move and act as a cooling for the pump. This is the same disign that car makes follow today. The pump doesn't have to work as hard to get the job done. The cooler you keep the pump, the cooler the fuel, the longer the pump lives.

[402bigblocks10]

you have a very good point, since my holley reg that i got with my pump has an out port on it, can i use that for my return, should i try that with the reg i have first

[Melonhead]

Look at the part # of the regulator you have. If it can be used as a by pass, then yes. If it is a dual feed and says nothing about by pass, NO. If the last part is you, I would look to upgrade to a by pass style of the same company. What ever suits your needs and won't break the bank.

[wild572s10]

Hey 402 pictures in album look good

[1090s10]

love the site. cant stay away. the problem with with fuel p.s.i. is voltige drop. put in a relay or a solinod. wire it to the battery and use the same wire to to triger it

[402bigblocks10]

thanks for all the info melonhead, ill look into that. thanks wild572s10..... and 1090s10- i have the circuit on a relay, the relay is powered by a power block which is fed directly from the battery

[HardinValleyMagic]

Nice pics! Roller valve train, cage. NOT TUBBED? Killer start though!

[Melonhead]

thanks for all the info melonhead, ill look into that. thanks wild572s10..... and 1090s10- i have the circuit on a relay, the relay is powered by a power block which is fed directly from the battery

Your welcome. I hope it does cure the problem. At least this change will allow your pump to live.

[402bigblocks10]

thanks hardinvelleymagic----roller is the only way to go, its pointless not to go roller- nope, not tubed, i have room to if needed, i want to get into the low 10s on 10inch tires, im having a fuel problem, there is alot of help on this site.....people are helping me... nitrous is next........ thank you to all who have helped me so far....

[HATFIELDSCHEVY]

do you have a rev limiter in the pcm shutting the fuel pump off.

[402bigblocks10]

no, no pcm or msd just hei

[85SS]

Nice truck! Good job. I had a similar problem on my 383 sbc, it would drop psi at around 6000. I had to do away with my -8 an fuel rail and run 2 seperate lines to the carb from the regulator. That help mine, but still would drop some. So I changed my fuel filter from a regular in-line to a fram canaster type. And that made all the difference. Just an idea, worked on mine.

[402bigblocks10]

im using a canister style filter now, maybe ill try the dual feed thing

[harleyboy]

hey just seen the pics and you do have a good looking blazer hopefully you get it fixed.