Yeah I see what 1racerdude is referring too. When I originally posted this, the whole idea was to get as much hp as I could out of an engine that would mainly see street use and use pump gas. So that big old nasty cam theory is thrown right out the window for me. Plus I will not go carburated or switch out from a LT1/4 intake setup either. I realize that I am only limiting myself in certain areas but that is what my main goal is ; to keep the LTx style equipment and get what I can out of the car. Now if I wanted an all out drag car, I wouldn't even be using a cast GM LTx block, it would be something more along the line of an aluminum Donnavan block. But that kinda defeats the purpose for me, as I don't want a single purpose drag car.
Hope this helps a little.

L8R

 

So if the stock intake manifold takes 10-12% of flow off, how much can you help the LT1 intake with porting and such? How much do you think making the plenum volume bigger would help?

 

IMO there is nothing ya can do to FIX a LT-1/4 intake. Ya can put a lot of money into it and help some.Ya can't change the runner length and ya can make up (if ya need it) for the plenum some with a 1300CFM TB.
The best place to put your money is get up with Bret and get one of his modified Holley Stealth Ram's.Or get a SR and adapt it to your set up. The height has to be shortened to clear cowl,PORT match(not gasket match) re drill the bolt pattern,port and ya got something. The runners are about 2" longer and a 1300TB works wonders(if ya need it)
Have done 2 with a modified SR and both cars picked up BIG time(not Bret's but similar).One was a Wilson and cost $2500.00 for the mod's.Both had my cams and were capable of using the intake and both were built 383's, one on pump gas.Seems like between 5" and 6" intake runner length (10.5-11.5 total length) is a sweet spot for a 383 with a good set up built in and a good tune.

 

We did some testing at Thunder on the LTX intake manifolds. A stock LT4 intake will knock 25 cfm off of a 280 cfm intake port. However, we've been able to get 15 of those cfm back with specialized porting.

 

IF that's bolted together on the bench that's real good,but the runner length is off to make max TQ&HP.Didn't say it wouldn' t run ok,but there is more available with longer runners.

 

Either way they'll be frigin sweet but there damn spendy!

 

Well if I decided to go with the AFR's, Single plane intake for EFI it would definately have a big stupid 250-260@50 solid roller with 650+lift to make use of the extra air and make some serious power but I think I will stay with my LT1 parts for now and be satisfied with a high 9sec. streetable car. Later Clint

 

My thoughts exactly, only I would even settly for mid 10's on the juice.