So I know this has been discussed before , and prob at length ! I’d like some honest input from those who know and have thrashed both ! Fresh 455 almost ready to pick up from builder. It’s .040 over , true 10:1 Comp cam .499 lift maybe 236/238 duration 113,lobe sep. I DONT HAVE CARD IN FRONT OF ME, but healthy street/strip cam. Holley 850 4781-1 rebuilt. MT headers with 2-1/2 pipes stock distributor with lectric Ltd conversion Now the question is intake. I have an sp1 untouched or B4B with the divider cut down and a little plenum work , ports untouched I understand the sp is more of a top end intake and I’ve run one on a similarly prepped engine and it pulled well. Am I better off with b4b for street and occasional track use ? What say the experts ? Thx guys !!!
What gears do you have? Will it have one of Jim's 9.5" converters? The crossover point is about 4500 RPM.
If u have the hoos clearance I'd run the sp1. With good gears I'd be willing to give up a little low bottom end.......the gears will help counter act that....t gain top end
SP1. From the minute I tried this intake, I never looked back. Had it on my last motor with aluminum heads. Never noticed any loss in low end. There is supposed to be, but I never missed it. Not necessarily a bad thing for traction, especially on the street.
Awesome guys thx ! I was kinda hoping to hear that as that’s really what I wanted to run. I asked because I feel I have a really solid combo here and didn’t want to give up any on the intake ! I know b4b would work well, but really trying to max out this combination thx again
Keith Smith did this 20 years ago.Contact him and he will give you the details.I saw him do the test.It suprised us.
I found this, but it was SP1/SPX. https://www.v8buick.com/index.php?t...ts-comparing-455-intakes.280827/#post-2315823 What were the results of the B4B/SP1?
When the local machine shop finally works thru it's backlog of jobs, i plan to dyno this exact comparison (SP1 v. B4B) with 3 different carbs.
I have an early Stg 2 B4B that I plan on running on my 464 build that I ran 10.40s with it in Buizila but was running a SPX and a Dominator. Be interesting to see the difference in performance
I have ran both intakes, when I switched from the B4B to the SP-1 it knocked a solid 1 to 3 10ths off the ETs over several passes. If I remember the 60' times with the B4B were just a little better. On the street the B4B seems to have a better part throttle response. Bob H.