I know, this topic has been discussed to death. I already read the archives.

I was just curious what you guys were running. I would like to have 350 to 400hp at the wheels with 350 or 383 stroker. Hopefully I can use CFI but if not, what TBI setup would support this? I was thinking of a TB with 2 inch bores and a low profile manifold that will fit under the stock C4 hood. I will be prominating when I build the motor. Thanks!

 

lets pretend you have a 3rd gen and we can overlook this small detail. (don't mention it is in a vette )

 

 

I'm always interested in the issue of the cross-sectional
area of the runners of high performance intake manifolds.
The advertising for various TBI friendly manifolds is
not encouraging, keep your eyes open for info.
I also have hood clearance issues.

 

Low profile intakes for TBI... the Edelbrock isn't shabby for ultra low profile. I still prefer the carb intakes like the Stealth with a thin adaptor plate (that excludes Holley's 1" monster).
Also you can use a drop base intake if you have access to a ball end hammer. Just pound out the side passengers side to clear the IAC and TPS. If you use a newer (91+) style TBI that has the 3 triangle type TPS weather pack then you don't have to pound as much . I don't know how your engine sits but that also determins what will fit. If the engien is slopped differently than the hood then you'll be limited with the diameter of the air cleaner. You want to fit a 14", anything smaller is going to get dirty FAST. Even if you only drive it once in a while a 10" filter on a 400hp engine is like a 4" filter on a stock L03 .

 

i am swapping out my Xram plenum to a 7.4L GM TB sooner or later. allparts ordered and in. it appears i have room to spare under C4 hood. edelbrock oval AC clears the linkage nicely(about 3 &1/8 inch high). will keep the modified weiand single plane intake. 1/2 inch howell adapter plate. 7.4L GM TB is only 2 and 1/64 inch high. maybe this Q is better asked on CF forum as it is specific for vette..

 

Ron,

I remember you were doing this. I may have to go with Pats milled Wiend if that will fit better.

 

actually i would use the weiand cut height as a benchmark. it appears i have room to spare. in fact i ordered a spacer from turbo city. 1/2 inch. whether this is a good idea i dont know. it effectively adds to plenum volume and plenum height. effectively restores the original height of weiand. i bet the other single planes might clear as well. like the holley TBI manifold. might be close however. the edelbrock air cleaner is what gives me the room to play with.

 

I C. So a dual plane sits higher than a single plane because of its design? I would hate to lose the low end torque. A stroker would probably make up for it.

 

not sure about that. i think most manufactuers post the height on the net. i like the Holley since it is a bolt on and i presume the linkage is a good fit. plus already 2.00 bores for TB's. plus no adapter plate(1/2 inch) so you pick up 1/2 inch. . as it stands i may need to do some custom fabbing when the 7.4L TB goes on on linkage(s). as far as other single/dual planes might be a tight fit or a no go. it was suggested the single plane works well with a TB setup vs a dual? don't know why.

 

Here is the x-celerator's specs.
http://www.holley.com/HiOctn/ProdLin...AMSM/7546.html

http://www.holley.com/HiOctn/ProdLin...AMSM/7547.html

Theres 2 different runner styles. Seems that the 7547's powerband is 500rpm higher but overall height is less.

Hmm...maybe a single plane works better because of the spray pattern and atomization of fuel by the injectors as apposed to a carb's fuel bowl setup.

 

my experience with xram is that the spray coats the bottom of plenum. pretty obvious when you look past a cracked butterfly. condensation on floor also when cold start or cold temp as well. now the dual plane with divided plenum maybe some of the same. the divider offrers another area for atomization to condense. also it was said the intake runner can accept fuel from entire plenum(single plane) as no divider rather than one half of plenum. the width of the top of intake is narrower than the spray of the TB injectors and TB venturies. seems a divider would just add to the issue of surface wetting. this is just some of what i read.

 

Thats why i dont care for the Xram. I would rather the 454 TB directing fuel directly into the intake. I think the small upper plenum of the X is also a restriction. Does pat have flow #'s on his site?

 

yea when i put on the xram i had no idea regarding cold weather. now here in wis the temps are dropping especially mornings. the xram strong point is that it is a bolt on and fits the hood. it is only alternative to CF cept what i am doing(7.4L) BUT that requires a lot of fabbing and will not be as cost effective. since a cam is going in i wont be able to compare results. with current set up 222 rear wh hp and 265 tq but the day was 90 and high humidity. car was jetted(?) rich 11.9/1 as well.

 

I hear ya. If theres too much fabbing with the 7.4 I may not go that route. I dont have access to as many tools as i used too, working in IT and all. I would like to be sure that my setup will "work" for my engine setup. Sy1's are expensive and I dont want to get rid of my wipers to use the Offy. Seems that ben is having some trouble with his as well. I would also like to use the prominator with my laptop. Hopefully Ken will come through for us with the CFI.