I recently purchased a '66 Skylark 455. It came with a tiny Holley Street Avenger 670 carb and a Poston S Divider intake manifold. I'm having someone set up an Edelbrock Quadrajet 795cfm 1904 carb at the moment and I was wondering if I should ditch the Poston intake. I've read the conversations on here about this intake and I feel it has mixed reviews (mostly negative) and alot of threads about this intake are dated. I'm not sure if it is the newer version with the plenum divider milled down or not yet, but it does have a carb spacer or adapter. I have most of the parts and have plans to build a TA Stage 2 462 10.5:1 compresion engine sometime next year to go in this car. In the meantime I want to enjoy the car until I get the 462 built. I do have new SP1 intake manifold designated for the 462 that I could install and ditch the Poston. I'm worried about hood clearances though. Is the Poston so terrible of an intake manifold that I should remove it and find something else until I get the 1904 carb back? Thanks guys Current 455 enigine specs/mods from what I dug up on here from the builder: -.060 over '71 block -.025" milled '71 heads -Poston 112A cam -High flow oil pump gears/springs -MSD 8552 billet distributor -Built TH350 -12 bolt 2.92 posi, soon to be 3.42
A larger Carb over the stock 550 or so cfm Cater AFB will have nice top end gains even with a not so great duel plane Intake ! I have seen gains of 8 to 15 HP. Duel planes Also love at least a 1/2" spacer on top of them.
It's there I'd use it for now, just get the qjet on it and it will be fine, i would say for sure put the spacer. That 1904 qjet edelbrock is a nice carb I've had a couple of them.
I ran a s divider for years on a mild 462 830 cfm holley annular carb 9.4 comp Poston 113a cam Mt ss headers Sp 400 trans 3.90 gear For it to be a basic rebuild it Ran very respectable numbers at the track! It made tremendous torque from idle to Around 5800 rpms. I would run that intake I never had any complaints about mine. Also mine liked a 1 inch spacer also
if you know you plans underway for a new motor, why spend anything extra on this unit that going to only be there a little bit. that's a few hundred bucks that could go towards the end goal. use what you have and enjoy. 10 or so hp you wont notice on the street
They need the ports opened up to match the heads. The one I worked on was way smaller than heads. That and aforementioned spacer really helped but....in the end an out of the box Edelbrock worked just as well......
