Two part question about my heads, and 383
 

I was just about finished with my engine. I have every thing bought, all machine work done. all that needs to be done is assembly. At the last moment I decided to go with a different set of heads. I was going to use the alum L-98 vette heads, bigger valves installed, and ported and polished. I am thinking about going with a set of Dart pro 1 alum heads with 200 cc intake runner.
this is what I am building if some one would run a dyno useing both heads.

383
10.3:1 compression
5.7 inch rod
Comp cam Hydrolic roller
276 advertise duration
.502 lift intake side
.510 lift on exhaust side
going to use 1.6 roller rockers
Eld air gap intake
750 holley dp
I would like for some one to run numbers useing both set of heads, the L-98 heads I have flowed 227 on intake side, can not remember what the exhaust side flowed.
I can get these heads at a really good price, just not sure if it is worth it or not, the Dart Pro 1's have not been ported or polished, they are straight out the box.

Right now I have the L-98 heads ported and polished ready to bolt on. I am looking at buying some Dart pro-1's. If I go on ahead and do this, I am going to port and polish these Dart heads my self. My question is, ( I think I already know the answer ) when I am through porting and polishing, are these heads going to have to have another valve job? these heads will be brand new out the box. Is there any thing I can use to put around the valve seat to keep them from getting hit with the porting and polishing tool? So I won't have to have the valve regrind?
Sam





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Sam

The only Dart Pro 1 airflow file i have is for the 215cc heads, with 2.05/1.60 valves. Running through small tube headers and mufflers, i came up with this (very impressive IMO)

rpm hp tq
2000 160 421
2500 206 433
3000 254 444
3500 307 461
4000 358 469
4500 403 470
5000 432 453
5500 444 424
6000 434 380
6500 409 330
7000 372 279

With a pair of L98's with 2.02/1.60 valves (i increased intake/exhaust flow by 10% for the porting, proably not accurate)
rpm hp tq
2000 165 432
2500 213 447
3000 261 458
3500 314 471
4000 362 476
4500 405 473
5000 432 454
5500 441 421
6000 428 375
6500 398 322
7000 358 268

Remember, this is a computer simulation and not entirely accurate by any means. I would think the Dart 215's would make more power, because the flow is pretty darn good (269/174 @.600" lift).

227" is enough to support 467hp.....price is right too!!:cool:

Either way, alum. heads would be good with that compression ratio.

your cam is a little mild to run the pro 1 heads. i would stick with the vette heads. not only would the motor have more torque but they are already done. i don`t know what experience you have porting heads or if you have a flow bench but if you don`t have either one, i would`nt port the pro 1 heads. they cost to much to ruin if you don`t know what your doing.