My 455 dynoed at 430 HP and 522 lb.ft. with an 850 double pumper. With the 800 quadrajet it dynoed 30hp less and about 30 or more foot pounds less. Sent it to a very experienced old hot rodder who has rebuilt a s**t load of quadrajets and he didn't find all that much that would point to such an obvious loss of power. Little dirt in the jets (not sure how much as I did not see) and slightly worn accelerator pump. Also, the secondary spring tension was a little weak. Thing is, with the Holley, the engine kicked RIGHT over, seemed more responsive, idled MUCH smoother and made way more power. The QJ took forever to kick over. Flooded, finally kicked over, idled a bit rough and just did not have the same throttle response. Seemed lazy at finally opening up, while with the holley, it was like a friggin sled dog being whipped. NO DELAY and very responsive. What do you think??
more cfm and with the dp, quicker bigger pump shot-my car picked up a solid tenth at the track ten years ago with a 850dp-but-lost 4 mpg!! the car was much snappier at low speeds, i think due to the dp. I'm a little suspect of 30 hp, but otoh, a tenth in a 4000 lb car is a lot from jsut a carb change, so it could hav ebeen 30 crank hp on mine as well
Yeah, and since I had to bring the engine home yesterday I won't have a chance to see what the rebuilt QJ would have done on the dyno. I'm almost tempted to put a holley on as I don't really give a rats ass about mileage. :laugh: I really had my heart set on this QJ though. Not sure if my stock snorkel will fit over the DP unless I use a spacer maybe? Then it's a hood clearance issue.ou:
Something I think is wrong with your QJet. I love my Holley! No problems. I recently took a lot of jet out of the primaries so I might get some mileage, if I can get the trans to work right. The Q-jet I used previously had a John Osborne rebuild, but had a hard previous life. It never worked correctly at WOT. One little secret I have found on the 850 DP is to set the idle a tad rich. When your car is cold, it will crank and idle like a fuel injected engine. No choke needed.:Brow:
Is it the right one for your car? They may look alike. The 69's should fow 750, but just read that the factory limited the rear throttle plate? Maybe find a 71-72 carb (850). Also a list of mods can be found in the "Guide to GS Buick", PM me if you don't have it. Rich
Your quadrajet was most likely too lean.What jets are you running? I have 76 jets in mine. I also ran a comparison test with my quadrajet and a Holley 1000HP. The Holley gave me a 10HP and 11 lbs increase over my quad. Not enough for the $700 price tag in my opinion. Tim
I just found out it had 68 jets in it. The guy put in 73's. Also, it had no power piston spring. :spank: The people that "rebuilt" it before probably forgot to put it back in. o No:
Thanks Rich. Yeah it is a 72 big throat. I got it off a 455 out of a 72 junkyard LeSabre with supposedly like 80k miles on it. Not sure what the numbers are exactly but the guy rebuilding it did identify it as the "good" one.
Tim your right i have a 850 Q-jet edel 1910 i sent it to jw he ran it on a motor like mine and a 950 holley. 950 made 6 more hp and used 20% more fuel
I think the reason many people use holleys is because they are simple to adjust and tune, not just for a couple extra horses.:3gears:
Have a similar power build 448 HP 533 trq. Was dynoed buy engine builder with q-jet (72 q-jet) that was FULLY rebuilt by a 30year plus q-jet builder on the final dyno with q-jet and 78 jets still was 22 hp (minimal trq difference) short of an 850dp holley out of the box. motor was starving at top with q-jet. i originally wanted a little more stock/sleeper look and use a q-jet but that started to change plus my car sounds NOTHING like a stock sleeper. was going to put a 850dp on it but it needed full rebuild. then I got a good deal on a new 950HP Holley and put that on with a 1" spacer and the car starts, idels, is snappier at ALL throttle points. Plus a good increase in "Seat of the pants" feel which is what we all like! This motor is liking the Holley and I never built my car with any concern for MPG anyway. Its a:dollar: weekend toy!
Believe me, I am still considering this. Everything you described was evident even on the dyno looking and listening to the engine. Will a stock ram air assy fit over the holley and still clear the hood with the spacer needed?
No it will not fit. I have a short (2 1/4 i think?) K&N top flow air cleaner on it now. i do have a GS hood and snorkel for "show" only though. my car is not a real GS.
Looks beautiful man. I really want the snorkel on there though. I have the K&N element I was gonna use though. The lid I think will be slightly open due to the height of the element but not too far that the hood won't close. Engine builder said that the breather hose which runs into the air cleaner from the crank case is crucial for limiting moisture buildup in the engine (he explained it all but I was like dizzy) and he said moisture is a huge sludge builder upper. So I want to use the breather fume recovery thinga ma jiggy. Bummer about the holley height issue though. That friggin sounds badass with that carb on it.
