950HP Jetting

[oldandtired]

I have a 950HP and wondered how much I can jet this thing with out messing up the balance of the carb. It's currently running way too lean.

Front 82
Rear 84
Air bleeds 72
Squirter 31
Power valves 3.5

Thanks, Dave

[chevyart]

hey old and tired. front is probbly ok. you say power valveS so i assume one is in the rear, i would remove it and go uo aprox 8 jet sizes. i like idea of power valve in front and i run the exact same setup as you describe for your carb, except mine is about 820 cfms.(750) with hp center section art

[oldandtired]

Art, Thanks for the info. I have a plug, and 90's & 92's to try.
Dave

[chevyart]

let us know how you make out with the jet changes. we all learn from each others experiments. watch out for that size 90 up front. sounds a little large. could load you up driving around i the pits. good luck art

[chevyart]

let us know how you make out with the jet changes. we all learn from each others experiments. watch out for that size 90 up front. sounds a little large. could load you up driving around i the pits. good luck art

[wmeabates]

Dave,This is from the build sheet of my pro systems holley hp 950. Primary main 76 [72 to 78] 6.5 power valve.Sec.main 86[83 to 89]power valve pluged.Hi air 36 all 4 low air 76 all 4.Bill.

[oldandtired]

Multiple errors on the set up. Lots of trial and error (and fuel) and here is what runs best.

Front 84
Rear 88
2.5 power valves (F&R)

Idles like a champ and the throttle response is crisp. After testing the PV's, I discovered one was actually a 6.5 (unmarked) and I had leaned out everything trying to compensate for this rich condition.

Thanks to all. :)

[bluedawg357]

Dave,This is from the build sheet of my pro systems holley hp 950. Primary main 76 [72 to 78] 6.5 power valve.Sec.main 86[83 to 89]power valve pluged.Hi air 36 all 4 low air 76 all 4.Bill.

That's identical to the build sheet from my prosystems. If you don't mind me asking what are you running for an engine, they say no off the shelf carbs. I am having to run a spacer as the accerator pump hits an intake runner. Just curios.

[wmeabates]

Bluedawg,That carb was on a 412 sbc 3200# car.That carb never ran like I thought it should.I tryed it on and off last year with different settings with a best of [email protected] last day of the season I put on a new aluminum ultra 850 and went [email protected] think the 950 could use adj.emulsion metering blocks for more tuning but Prosystems told me I didn't need it.Looks like just a bunch of holley parts put together with stickers to me. Just my opinion.Sorry for the jack Dave.Bill.

[bluedawg357]

also sory for hijacking the thread. My brother suggested the prosystems and after some research it seemed like a good deal. I havn't put it on yet, hopefull that it works great, but your build sheet matches mine almost identical & I don't think that my 400 is nearly built as much as your 412. well see.

[oldandtired]

Hey, it's all good!