Racing Fuel Systems

Where the hell is everybody?!

I have an old 9375 (no dash) here that somebody 'converted' to E85. I need to un-convert it, does anybody have a handy list of what all the bleeds & IFR (swaged tube style) were as stock?

And it's been 20 years since I messed with one of these, these 3 circuit blocks are hurting my brain. Are these holes on the bowl side original, or something that needs to be undone?

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So it seems we are up and running again! Those are the intermediate feed restrictions, older non HP metering blocks. The pinched idle tubes were I believe around .029, .053 for the bleeds. intermediate bleeds were open. Start around 92 for jets without PV's.

Cool! Well, sort of back up. If you add an attachment it refreshes the page or something and dumps any text you'd already put in, so this is an attempt at reconstructing what I'd written the first time...

I can't find any info on 4500s, labeled photos or whatnot like are everywhere for 4150s, not even in books (the kind made from dead trees). If I have this reverse engineered correctly, the innermost air bleeds are MAB, that's pretty obvious. The middle bleeds are intermediate, and outer bleeds are IAB? And if 2 circuit 4150 blocks are used then the middle bleed turns into the IAB and the outers aren't used?

I think this will be better off staying as a 3 circuit, it's a dumb experiment on a very very mild motor. I've done this before with a 9375 like 30 years ago, on that one all that was done was adding PVs and pulling out a bunch of jet. It worked fantastic, but then that was before I knew it wasn't supposed to work.


These two discharge holes, supposed to be here or were they added? All the Ebay photos I look at for reference show only one hole, they don't have the one below the t-slots. There's so much that's been messed with on this thing I just don't have any point of reference to know what's what.
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[quote="jmarkaudio"] The pinched idle tubes were I believe around .029, .053 for the bleeds. intermediate bleeds were open. Start around 92 for jets without PV's.[/quote]

So these idle tubes that pin out at .048" means buy new idle tubes, huh. ;p

These metering blocks are threaded for PVs but PVCRs are blank, not drilled. I'll be adding those, probably start around .055" & 80 or 82 MJ?

Ah jeez, somebody hogged out the boosters for oversize pins, around .234" instead of the standard parts I have in stock at .211". Crap crap crap crappity crap.

(forum ABSOLUTELY REFUSES to put the images in the correct order no matter what I do, so individual posts it is...)

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