obZidian

iTrader: (2)

Looking for a LS7 specific single plane manifold. I know there are a couple for the Ls3 and L76/L92's but its for a set of LS7 heads.

Also, what kind of filtration options (with MAF) are there available for a 4bbl TB? A carb hat like the one's used for a turbo, blow-throw carb application?

What kind of CFM limit should I be shooting for a N/A 427ci 12.5CR on a moderate/high hydraulic and close to 400cfm heads?

1200cfm? 1500cfm?

obZidian

iTrader: (2)

http://paceperformance.com/browsepro...-Manifold.html

Found one so far. GMPP has a large manifold for a 4500 4BBL TB but it maybe too much for what the build needs.

Beau@SDPC

iTrader: (14)

http://sdparts.com/details/gm-perfor...parts/25534394

def not a 4500 flange on the GMPP one. Even on the LSxLS7 one, its still a 4150 flange. Nothing in a 4500.

obZidian

iTrader: (2)

Another question:

What kind of driveability should one expect (street duties) from a single plane, 427ci motor with a 4BBL EFI TB and a cam about 32*-38*'s of overlap?

Just a general consensus. Is it more aggressive than a sheetmetal with a 102mm TB or more tame? Can it be docile where one can drive it comfortably on the street of will it be finicky?

obZidian

iTrader: (2)

The 4150 Tb, I think, will be enough. At this point I'm more concerned with how it will drive around town then finding the parts. I appreciate the heads up!

Beau@SDPC

iTrader: (14)

They work rather well. The CID will soak up the duration, but alot of guys like to run the 108-110 variety of lsa with a larger degree of cam for some reason. We ran a 112-114 and had stellar results with less overlap and it made just as much power and still sounded well within the rumpity rump range that people like.

obZidian

iTrader: (2)

Right, that close of an LSA is going to make the idle choppier but you also shift the bandover.

Thanks for info.

Irish350

iTrader: (14)

From what Ive read your new intake will be more drivable/tunable than a sheetmetal intake with a 102, but i repeat things i read online, so what do i know?

Beau@SDPC

iTrader: (14)

Im not sure if I would directly relate LSA and a choppy idle. It can definitely make the power peak at diff rpm and not have as good a curve, but each intake/head combo will take a different cam design.

obZidian

iTrader: (2)

Not directly but the amount of degree's of overlap will increase with identical duration.... but I'm preaching to the choir, it seems.

1CAMWNDR

iTrader: (21)

I have a 421" motor with a Victor Jr. and Accufab 4150 4BBL throttle body. Cam is 239°/247° LSL lobes on a 110° LSA and 108° ICL (+2°). I think that cam has 24° of overlap and if I had better heads it would have more intake and exhaust duration.
I think with your LS7 heads you could use more cam; but the 4150 will probably be plenty big enough for you. Use a carb hat with a 4" opening.

rem308winvtr

iTrader: (24)

i have a beck sheetmetal for a ls7 if you want to go that route