Motor Build

9

93missl96

Forum Member
Im building a motor right now, id like to know how much HP/TQ i can expect from this setup. If you have any ideas for improvements, let me know please.

60's Corvette Block bored .040 over.
Speed Pro .040 pistons.
3.48 stroke
5.7 rods
Vortec heads- P/N 10233906 with stock 1.94/1.50 with 64cc chambers. Stock springs, recommend me a set for cam below.

Considering these rocker arms- http://www.summitracing.com/parts/SCC-SCP1036BL/

Cam specs.

DURATION AS ADVERTISED INTAKE: 308° EXHAUST: 318°
DURATION @ .050 INTAKE: 234° EXHAUST: 244°
LIFT @ CAM (Lobe) INTAKE: 0.325" EXHAUST: 0.34"
LIFT @ VALVE INTAKE: 0.488" EXHAUST: 0.51"
LOBE SEPERATION: 112° INTAKE CENTERLINE: 107° IDLE VACUUM @ 1000 RPM: 11"

Running this intake with a Holley 770 cfm carb from a 68 Camaro- http://www.summitracing.com/parts/PFS-52030/

Also will be running a Mallory distributor, dont remember the P/N off the top of my head.

Will probably be dropping this setup in our S10 come spring time. May get bigger valves for the heads. Will be running a th350 for now, possibly with a 3200 stall.

Im just trying to figure out how much flywheel horsepower i can expect.

Thanks Motown :)
 
Last edited:
300 - 325 hp is my guess. Getting a head with a 2.02 intake valve would help. Also a camshaft with a tighter LSA will improve your hp. Home much compression is it going to have
 
That intake will not bolt to vortec heads, you need a vortec specific intake.
The vortec heads will only take around .480 lift before the retainers get to close to valve seals, springs start to coil bind right around there to. With the those rockers your getting about another .030" of lift so your definatley will have a problem. Stick with the stock size valves, vortecs flow good and unless the fully ported by someone that knows what there doing shoving a bigger valve hurts them
 
too much lift unless the guide boss have been cut/seals changed.
pushrod holes will have to be opened with that lift or 1.6 rockers
Xe268 is popular with those heads
 
Pro Systems Carbs would set him up with a 780 Holley and it would work great. I always reccomend them. Their custom carb costs the same as an off the,shelf holley hp but its made specifically for your engine.

Some simple head work and a hyd. roller cam away from 400hp+
 
The comp cams beehives and retainers fit without machining, I have them on my vortec heads. Biggest problem was finding shims that let me get the install heights back down to 1.800" (they installed about 1.920"). I measured .555" of clearance between the retainer and the seal, so I figured I was safe for .525" of lift total. I also went to screw in studs instead of the press in. I picked an XE274 for mine.
 
Don't use that intake either. I would use an RPM AIR Gap, too much palenum volume for that set up. Air speed will be your friend with this set up. XE 268 or 274 works good with those heads. Should make just about 350HP. Be sure to check the port alignment, and match to the heads. It's easy to match the last 2 inches or so of the intake to the head, and keeps from killing the air speed by eliminating the tumble and turbulance of a mismatched port. And yes, even if you use a Victor Jr you need to check the port alignment/size.
 
You must log in or register to reply here.
Back
Top