u can run 9.5-1 compression and run over 20 psi of boost on pump gas, its been done tons of times
Yes WITH INTERCOOLING....
Not going to happen unless and until you get the charge air temp down.
That requires intercooling or water/methanol injection.
They only other way to run big boost without intercooling is to run a very low compression ratio.
The aircharge temp from the turbo at 20PSI boost will be approaching 200°F
On a 80°F day
Its pure physics.
"small valve truck heads" could very well be a beauti set of 041 castings
ya they primarily came on truck motors.
These "truck heads" are equal or better than the famed 461-462 fuelie heads
When these are home ported they flow over 240cfm. That a long way from the crap the poster is working with.
180 to 185cfm in 115 cfm ex. Thats what he has got.
Another example of a small valve truck head is the 305HO head
#4416 I get over 230cfm from these heads by home porting them.
These 416's come on trucks too.
So do 062 vortecs 059 305 vortecs, 083 TPI heads etc
The tpi heads can be ported to 260+cfm.
This is probabily what the 9sec motor has as the TPI manifold bolts to them.
These heads are ALL "TRUCK HEADS" and all are miles ahead of the crap the poster is trying to use.
Any 14 year old who can tweek a mini bike can do a pretty fair job home porting these factory heads.
There is no free lunch. You need head flow to make the kind of power you are talking about.
Right now the gears are the least of his problems. Untill you actually start makeing some horsepower, no point in changine the gears.
You are working with a 160HP cylinder head.
NO BS there.
Copper head gaskets will not fix it.
Get some better large chamber heads and port them yourself.
There are many many to choose from.
EG GM 76cc 920, 441 487 336 EG World products sportsman II WP S/R torker 76cc.
RHS iron lightening 200
The $50 GM 920's will port up over 240cfm and 190++ by home porters ex Pros get a lot lot more.
2.02x 1.60 valves. You should be able to completely build a set for under $500.
You can buy rebuildabe one for $50. They are "truck heads" too.
The one thing you are dead right on about of the 224-224 114 summit cam swap.
The 234 cam is a bit too big.
I bet that 9sec firebird is using a efficient air to water intercooler, cooling down the charge air temp
to BELOW AMBIENT temp.
You say you can show it. Post a link where it is discussed in a forum or other web site BY THE OWNER OF THE CAR.
I know its possible and I know what it takes to achieve that level of performance.
Yup the twin Buick GM turbos work very well. (TWIN being the key word.)
Last edited by F-BIRD'88; 07-23-2012 at 12:25 PM.