Ok, I am thinking of going with an SP1 intake manifold with a Dominator flange. Can I bolt a Holley 4150 /Demon 850 to it? It does have two bolt patterns...JIM
Ahh, plenty of room to go up, (Stage 2 Scoop) Notta fan of adapters....gonna hafta make a decision... Thanks all for the replies...JIM
I’ve been looking into this exact same question myself. I want to replace my E85 Dominator with a 4150 gas carb since I lowered the compression from 13:1 to 10.5:1 but I want to keep my old KB Wildcat intake which has a 4500 flange. anyway, I see that there are a few 4150 carbs out there that have a dual pattern baseplate pattern. No need for an intake adapter for either application. this is just a single example: https://www.holley.com/products/fuel_systems/carburetors/quick_fuel/drag_race/race-q_series/parts/RQ-1000 Or depending on which 4150 carb you have, you can swap the baseplate with something like this: https://speedmaster79.com/Billet-Al...ate-Holley-Quick-Fuel-4150-and-Dominator-4500
if the sp1 has 2 bolt patterns, one may well be for a 4150, but yer gonna have to measure or try it yerself
Apparently, you need an adapter to go from 4500 to 4150. Not sure ifya can go the other way, if ya follow... I'm buying an SP1 square bore off the board and I'll be using my Demon 850 on it. The Dominator may go up for sale after a going through. Just can't see doing all that wrenching , heads, cam etc. and bolting my old Offenhauser 360 back on.... Hey, did you toss yer old felpro head gaskets when ya went thru your motor? Could use if if ya got em hanging on a nail for mockup on your old block. J
Yes,you will need an adapter,or weld and machine the intake. I am running a ported 4-hole adapter with my intake,so I can run a 4150. I pin the adapter to the intake to do any needed blending. I have the part number for the adapter at work. I can post it Tuesday.
a simple 1/2 in adapter is all you need,. And when going from a 4500 to a 4150 there is no real work or interference whatsoever When goung from 4150 to 4500,..yea you create a bottleneck if yiu use the adapter but it would only show up WAY up in rpm range that a buick will never see,..one could argue it may would even benefit a combo,. Serving a venturi effect To "properly" go from a 4150 requires machine and hand profiling The dual bolt pattern on tge 4150 sp1 is qjet and 4150
I have one of those 1/2” adapter spacers. Yes,it would “work”,but the transition will leave potential power loss. Mock it up and see how it looks.
You're only creating more plenum volume,...the short turn under it wouldn't cause any issues in my mind as the air isn't sitting its hitting the floor and being pulled,..path of less resistance imo,.."I" would just go with a dominator and call it a day ha
https://www.yellowbullet.com/threads/4150-to-4500-adapter.365638/ Interesting read on using adapter to go from 4150 to 4500.....JIM
I swear years ago we used an adapter and it ran better than the dedicated Dominator setup....yes maybe that venturi effect Ben....
That is basically what the guys at Yellowbullet were saying: https://www.yellowbullet.com/threads/4150-to-4500-adapter.365638/ Got this one on my Summit Wish List: Check out this page from Summit Racing https://www.summitracing.com/parts/drt-62100007 Jim
Alot of newer carburetors have dual pattern baseplates. If you choose to run a adapter alot of times you do pick up power due to extending the intake runner length.
