doing a little reading and it seems worthwhile to try it. running a holley on a performer w/ 1" open spacer. anyone tried it and what were the results? thanks, dave
Dave i have a 850 Q-jet with performer and 1 inch spacer it pulls better upstairs.Did'nt notice any loss in low end.Don't have any track info on it.
Dave, what jets are you running and what cfm? Do you run a power valve? We just put on a 950 pro form. Smaller jets (4 sizes) in front with a power valve in front only. Car seems to really like it so far. Track test this weekend.
830 holley annular booster w/ the choke tower cut off. power valve on the primaries only. rear jet extensions and plugged power valve. 81 primary w/ .070 power valve channel restriction and 95 secondary. probably going to end up a few numbers up in the front and a few numbers down in the back. then i want to stagger the jetting and see what happens at the track. hopefully going to etown to race this weekend so no testing till next weekend. good luck on your testing let us no how it goes.
I have a 850 holley with staggered jetting 84 in the front 90 in the back Rear power valve plugged off 50 cc pumps front and rear . I ran about a tenth faster than you but your 60ft times are better, mine were 1.60s I also picked up bottom end with a 4 hole spacer rather than a open spacer.
Dave, do you mean staggered front to rear (pretty common) or left to right due to distribution issues? To really dial things in it seems EGT is what you should be watching: http://www.v8buick.com/showthread.php?t=6565 I have always run primaries lean and secondaries rich, but have never seen a need to left/right offset with the SP1 intake, although I've not watched individual temperatures as described in Tom's post. Devon
Left to right is what I thought he meant. The old school B4B liked it. Check this out... http://www.v8buick.com/showthread.php?t=111724&highlight=STAGGER+JETTING
I thought so too. I ran my old Offy that way due to one or two cylinders acting different than the others, I was only going by plug readings back then. I can see how a dual plane might need some help as well. Devon
thanks for the links and info.* thats what i had read also but it was on a chevy forum. the old gm high rise dual plane intake with the center cut down got stagger jetted. they even sold a carb that came stagger jetted out of the box.* the reason for asking buick guys is the chevy intake has the low side of the dual plane on the left and the buick intake the low side is on the right.* i had thought the reason for stagger jetting was to compensate the lower flow out of the low side runnerso No:* GM had info that stated the stagger @* 80lf....76rf76lr....78rrthen* jet up or down form there. this was on an 850 holley. was wondering if it would be reversed because of the high side/low sides being reversed between the chevy and buick intakes. anyone have any thoughts on this? thanks, dave
i forgot about the egt being mentioned, thats is another thing i would like to keep track of one of these days. right now just using a inovate wideband and looking at plugs. they are definately not even side to side so thats why i was asking about stagger jetting. thanks again, dave
Even similar combos will be so sensitive to jetting that I doubt you'll find much of a "rule of thumb" to go by. Your own EGT/wideband readings and ET/MPH will be your best guide, I'm afraid. It could be time well spent though! Devon
