Small Block & Big Block Chevy Specific - sbc383 stroker questions
505OUTLAWZWS6
07-02-2009, 05:30 AM
Hello my dad had a 383 built for his vette and it didnt really please him and it recently started knocking, so he is wanting to build it better this time and i am trying to help him with it.
Here are the specs of the original build:
Heads: Pro Comp Aluminum 210CC runner size, 64cc combustion chambers. 2.02 1.60 Valves.
Cam and lifters: Crane Blue Racer-#1064. Adv. Duration -300/310, Duration @ .050- .234/.244 Gross lift- .488"/.510" flat tappet
383 Eagle rotating assembly , dish (?) pistons.
Weiand single plane, open plenum intake.
SS roller rockers 1.6
Holley 750 Vacuum secondary, single pump
A few questions i have. From the research i have done, the pro comp heads are junk. I am trying to get him to go with the afr 195 heads. He has a set of 487 heads that have been gone through recently, bigger valves upgrade springs etc...but would they be any good on a 383? Any other suggestions on heads? What would be a better cam, as he was not satisfied with the one he has? He wants a good lope but the driveability too. The 71 vette never goes to the track, he just want a decent motor for a weekend driver. Any head and cam combos suggestions?
94 guy
07-02-2009, 06:48 AM
what year block are you planning to use?
505OUTLAWZWS6
07-02-2009, 07:23 AM
I believe it is a 4bolt main from early 70's? 71 vette
Isolde
07-02-2009, 11:54 AM
those 487s will never begin to approach the AFRs. Spend the $270 for a set of retrofit hydraulic roller lifters, and install COMP's Thumpr retrofit hydraulic roller cam. The smallest of the 3 choices. That, with the AFR heads, has pleased more than one of my customers beyond words.
kenSS
07-02-2009, 09:16 PM
def. get the AFR heads.
505OUTLAWZWS6
07-07-2009, 05:36 AM
Any other suggestions or combos?
ChevyS10sbc
07-07-2009, 03:49 PM
I would suggest 1.5 roller rocker arms. I dont think your cam is big enoughfor the valves to open that far. That was my problm on my 385 for awhile.
fast01
07-08-2009, 12:44 AM
What exactly is he not "happy" with? Driveability, power, fuel consumption? There are a million combo's that could be thought up, but to come up with something we need to know exactly what you're looking for. There are a few things in your combo that I would change if it were mine, but what makes me happy might be a far cry from what makes your Dad happy.
505OUTLAWZWS6
07-09-2009, 04:07 AM
It doesnt have the lope and the power he wants or thought it would have from what people told him
fast01
07-10-2009, 02:59 AM
Alright then. I can tell you what I would do in this case. This is by no means the best or the only way to go, but it's what I would try first.
I know nothing about Pro Comp heads, but you've got 'em, so you might as well use 'em. Unless of course you've got an extra $1500 laying around for some AFR's. If that's the case do it, but if you're like me you don't have that kind of money laying around. That being said, get rid of the old school cam. It's a proven grind and works well, but it's obviously not what your Dad's looking for and we could certainly benifit from some newer lobe designs. I agree with Isolde on the hydraulic roller retrofit with one of Comp's new Thumpr cams (I agree with the smallest of the 3 as well). That should give you the lope, a boost in power and maintain driveability. With the cam you'll probably have to change the springs on the heads to obtain the proper seat and open pressures and I'd lose the 1.6 rockers and go back to the 1.5 ratio. Lose the single plane intake as well. They are horrible on the street and kill low end and driveability (ask me how I know). A Performer RPM type intake will be more than adequate for your set-up and the power range of the cam. The last thing I would do is try the Fel Pro 1094 head gaskets to bump the compression a bit. This will help power and efficiency. Just make sure the pistons are at least .020" down in the bore at TDC or the quench will be a little too tight. When all is said and done you should be in the 450 hp. range with around 450 ft lbs. as well. If you go with AFR's you'll probably pick up 25-30 hp. on top of that. Also, bear in mind you're giving up some power to get the sound you're looking for. There are some better cam choices out there, but they may not have the exhaust note you're looking for.