jakesz28

iTrader: (9)

I'm waiting to here back from a sales rep. But does anyone know if the compstar series cranks have a 3.75 stroke for a 5.7 inch rod. I was told all they had was a 383 with 6.0" rod. I would like to run a piston with larger ring lands is the reason I want a shorter rod.

jakesz28

iTrader: (9)

Well they make a crank for a 6 rod and if you want one for 5.7" rods they can mill down the counter weights. Takes about another week and $80.

96capricemgr

iTrader: (1)

IMO you are worrying about nothing. On a 396 then yeah you want to keep the rods shorter than 6" for boost or juice but the rings on a piston for a 3.75"/6" combo are not that high as to be much concern.

jakesz28

iTrader: (9)

What if I'm going to spray a 250 direct port and second stage from a plate. 350 total

96capricemgr

iTrader: (1)

Then I think you better have MASSIVE heads and start at a smaller shot and see where it stops gaining. I would guess you are going to stop gaining long before you reach 350hp total.

jakesz28

iTrader: (9)

I have a set of brodix heads but at this time the numbers are lower then expected. I was hoping for 320+ on the int and 230+ on the exhaust.

Right now the're not much better then stock ported heads.


These are flowed at 28 on a 4.030 bore

int exh lift
195.4 133.5 .300 at 27.97
241.7 162.1 .400 at 27.96
264.5 183.6 .500 at 27.95
274.3 196 .600
283 203 .700

buffman

iTrader: (9)

on the OT did brodix finally make a set of LT1 heads?

jakesz28

iTrader: (9)

No but they will convert there heads to run on the LT1. Instead of welding up the head they will make the changes while casting a new head.

96capricemgr

iTrader: (1)

The reaon I mention the heads is I have watched someone Matt here and I both know switch from 175 to 200 jets and not gain anything, granted that was milder heads but it still demonstrates what I think you will find.

How deep in the 9s are you looking too run?

jakesz28

iTrader: (9)

I was hoping to get 700hp at the flywheel on the motor. But these heads won't allow that much so I may get some different heads. I want to be able to run low 9's on a 250 shot.

dhdenney

iTrader: (53)

Are those numbers out of the box?

jakesz28

iTrader: (9)

No this is an old set of -10 that have been converted to run on the LT1. I took a chance when I got them because they were older castings. By the look of the ports I expected them to flow a lot more. But the place that has them doesn't think they can get that more out of them.

The new -10's flow these numbers out of the box:
2.080 Intake 145 195 240 253 262 262 262
1.600 Exhaust 110 139 155 161 166 168 168

And will flow 320's and 230's ported.

dhdenney

iTrader: (53)

I guess that answers my next question. I was gonna say just have them ported but if the porter thinks it won't gain then not hardly worth the gamble.

jakesz28

iTrader: (9)

I think part of the problem is these are flowed on a 4.030 bore. If they were flowed on a 4.155 bore I bet the numbers would better. But I'm not running a 400 block.

dhdenney

iTrader: (53)

If I were you, I might try to find some better heads. Not that what you have is bad, but you are less than pleased and you are still at the point where you can change the setup without any work.