Author Topic: Got Hemi back from shop  (Read 2986 times)

Offline Mike71Cuda

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Re: Got Hemi back from shop
« Reply #30 on: September 17, 2008 - 05:03:49 PM »
Getting back to my original post.
When car idles and i rev it is strong all the way through, its only when I am driving the car does it sputter and fall apart. Could this be a fuel delivery problem? Idle ok, when at speed ok just middle bog etc. has an 8lb mech also have a elec. out back realize I did not put that in my orig post.
Also eng is not a crate motor but a new block and internals assembled before Hemi crates were made available
Thanks again fro all the advice
Smitty




Offline Supercuda

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Re: Got Hemi back from shop
« Reply #31 on: September 17, 2008 - 07:35:50 PM »
I wondered when we would wander back onto the path. Does it belch black smoke when this happens? It sounds as if you might have too much fuel pressure at the carbs. Do you run a fuel pressure regulator? It should be set below 7 psi, and 4.5-5.5 psi is usually best, if no fuel starvation issues present. What do the plugs look like when you pull them and look at the insulators/electrodes? We will get you sorted out somehow.

Offline Chryco Psycho

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Re: Got Hemi back from shop
« Reply #32 on: September 18, 2008 - 01:41:17 AM »
I would check the float bowl levels , if they are set too low it can stuble at mid throttle after the accerator pump is already open , possibly a longer duration cam on the accelerator pump could help but at mid throttle you should be pulling fuel through the booster & it shoudln`t lay down , lowering the fuel pressure slightly could help although I have seen holley carbs live ok with 7 PSI

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Offline Mike71Cuda

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Re: Got Hemi back from shop
« Reply #33 on: September 23, 2008 - 11:06:01 AM »
Sorry about getting back to the thread had some family obligations that pushed the car right to the bottom of the pile.
No pressure reg. All the engine guys I know (Jerry Stein-Teachers Pet racer Lou Vignona V&V Auto) say it should not need a reg. Single Holley 900 cfm. No smoke that I noticed. I will check the flow and add a cam pump if needed. We did that on my 440. Let me run teh car and pull plugs will get back to this thread once that is done thanks for the thoughts.
Smitty