Low Fuel pressure

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Re: Low Fuel pressure

Postby monza355 » Tue Apr 20, 2010 11:12 am

What do you guys suggest for the timing setting? Demon seemed to think 18 degrees. Is it a "put it where your engine likes it" or a specific degree? I would love to get my car running like it should.

On a different note, I would like to say you guys are awesome. There is some great info on this site.
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Re: Low Fuel pressure

Postby clintjohns » Tue Apr 20, 2010 11:54 am

nope it's a bosch #69552 - fits 305 v8 cab engine per every source i can find. I ordered it from Advance Auto yesterday..

I always get it close with a timing light - get the car running, the set it where it idels smooth and responds to the carb well. Then just lock it and leave it.
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Re: Low Fuel pressure

Postby chevy art » Tue Apr 20, 2010 6:17 pm

hey monza 355just setting it at 18 degrees really dont tell youa thing. you need to set it for total timing first(you can see with the timing light when you rev it up and look at the harmonic balancer and look at the total number. for a street engine probably around 34-36 degrees total is usually a norm for the timing on the SBC(could even be a tad less/ to do this you need to put a mark on the damper around 35 degrees in the advance direction. after all this total setting stuff you must look back and see what your initial advance is, and adjust your advance curve. i could tell you the exact , whole scenario, but it is a little long, but simple if you understand how the timimg in distributor works. hopoe this starts you in right direction
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Re: Low Fuel pressure

Postby cjbiagi » Tue Apr 20, 2010 6:40 pm

A stock HEI on most V8 Hbodies have about 22 degrees in the distributor. Setting the initial timing at a low idle (to make sure the centrifugal advance has not started yet) to 14 degrees will get you real close. After that you can try a little more or less and see what works best. Too much static advance can make the engine hard to start, especially when hot.
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Re: Low Fuel pressure

Postby monza355 » Wed Apr 21, 2010 12:31 pm

Thanks guys. I will check all of this and see what happens. It sure would be nice to get this thing running.
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Re: Low Fuel pressure

Postby chevy art » Thu Apr 22, 2010 12:26 am

hey monza 355 CJs post is right to the point for you. i was generalizing more towards racing type distributor setup with aftermarket ignition systems . funny, but i really dont know a darn thing about HEI systems or any of the stock type setups. i never stop learning though. i get these little tidbits from you guys every day art
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Re: Low Fuel pressure

Postby 72vega5.3 » Tue May 11, 2010 7:57 pm

monza355 wrote:So does everyone here agree that a stock in tank pump is enough to fuel a 355 with a 650 Speed Demon? I was under the impression that the stock pumps were not enough. I am having problems getting a good idle and also get backfires upon acceleration. I was told it is probably not enough fuel pressure. My pump is brand new. If I need a higher psi pump, what is a good one?


Was your car a v8 to begin with ? Also, is there a difference in pumps between 4cyl, and 8cyl monza's, and do the vega's carry the same pump
Im doing a 350 buick swap in a 71 next weekend, and wondering if the stock pump is sufficient for the time being.. I believe the stock quadrajet is a 730cfm. Buick typically have big carbs
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Re: Low Fuel pressure

Postby cjbiagi » Tue May 11, 2010 8:00 pm

Did the 4 cylinders come with a electric pump? I thought they had mechanical ones? I'm no expert on 4 bangers though. I know the V8's had the electric because there wasn't enough clearance for a mechanical pump. I still have a stock electric on my car which is also a 355 but with a Carter AFB. Never had a issue with it but I am not racing it.
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Re: Low Fuel pressure

Postby 72vega5.3 » Tue May 11, 2010 8:09 pm

Its electric on my vega. Its noisy :)
I wont be racing it, just a daily driver with dog dish hubaps
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Re: Low Fuel pressure

Postby gerbsinmd » Wed May 12, 2010 7:21 am

The 4 cyl, did have electric pumps. Had one in the 77 I put a V8 in decades ago.
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Re: Low Fuel pressure

Postby res0o7eb » Thu May 13, 2010 12:42 am

The 151 cu. in. Iron Duke I-4 uses a mechanical fuel pump.
The 140 cu. in. SOHC I-4 (Vega) uses an electric fuel pump.
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