cfabe

I'm going to be building a 400 to replace the 70s truck 350 with a TPI on top in my trans am. I'd like to do a custom setup using a drilled carb manifold. I've read all the related posts on here and still have a few questions. I've got a Computer Quadrajet laying around, could I gut that and use it for the throttle body as it has the TPS in it? Do you need an IAC or can you run without one? With say one of the Weiand manifolds, do you HAVE to use their fuel rails or will stock ones fit? Comments on taking a normal single plane EGR carb manifold and drilling it myself and epoxying in injector bungs. How much chip work will need to be done to get this running; I have the chip burning equipment but have just started to get into it. Who's got a setup like this running now? I know earlier this year there were a few people who had ordered parts. Any other comments/suggestions?

Thanks

airdeano

ok, using the carburetor intake is doable, but
the cost and gains arent there. by the time you
get the manifold drilled for injector bungs
make fuel rails, fuel rail stand offs...
id say youve got $400 into it. just get a GM
TPI off any of these boards or eBay.
the 400 (14% bigger 350) is fine with a TPI.
if your wanting some major power.. look to a
miniram or superram. the flow requirements
for the larger CID engines is tremendous.
but if you not going to buzz any faster than 5200
the edelbrock, or accell streetram will be
fine.
chipping will be custom. any good tuner should
be able to. keep cam selection 220@.050"
and 114 lsa if you think TPI. you can get a
lil wilder the the short runner manifolds.
the carb manifold runner is plain too small,
too long to build upper hp with FI.
as for using the carb as a throttle body...
yes it has a TPS, but again by the time you
have "made" it work.. youve got some $$$ in
something that will be restrictive on a 400.
performance speaking.
an "EGR, single plane manifold" for MPFI?
why?? emissions?? if you dont have to DONT!!
weiand already has manifolds drilled for MPFI
and i believe they have rails too. hooley, and edelbrock
have ready to run MPFI also.
airdeano

cfabe

thanks for your input, I'm planning on building this 400 with a real solid top end, I've got a TPI 350 now and I feel that while having real strong low end torque has its advantages, I'd rather build up an engine with a good high end, even if it does mean sacrificing some low end torque. The torque from a 400 TPI would be, IMHO, too much... too had to get traction and would likely shred my t-5 and rear end to bits.

Actually what I think i'm going to be doing now is converting a LT1 intake to work on my older block. Seems like it'd be close to or just as good flowing as a miniram, and I dont mind doing the work to get it to work. Pretty cheap too. Any comments on the LT1 intake?