HP/TQ output?

[88bluestar]

Estimated Torque and horsepower output?

Small block chevy. 9.8:1 compression 357 cid
790 cfm SMI Holley 4 bbl on 1" spacer, victor jr intake
Bowtie vortec 185cc head 2.00/1.55 valve 1.250 comp valve springs
JE 390 gram piston with low tension rings
45 lbs crank with 1.889 rods
248/252 @.050" .359"/.359" Lobe Lift 105 LSA Solid flat tappet
1 5/8-1 3/4 header, straight back exhaust with straight through muffler(3.5" dia)
Altitude 4,200 ft above sea level.

[lefty o]

roughly 450hp 410tq.

[mag2555]

If your heads are flowing 275 intake cfm@28" , at the lift you are running you could make 560 hp, but I do not think the Jr Intake will allow that in stock form.

[Steve.k]

roughly 450hp 410tq.

Id say that would be corrected hp. At 4200 ft the air is thin.

[lefty o]

roughly 450hp 410tq.

Id say that would be corrected hp. At 4200 ft the air is thin.

maybe, my internet dyno doesnt have a calibrated altimeter. lol

[Steve.k]

Thats very close to my altitude. From dyno corrected power to installed in vehicle and running nearly 100hp off of corrected number.

[randy331]

Estimated Torque and horsepower output?

Small block chevy. 9.8:1 compression 357 cid
790 cfm SMI Holley 4 bbl on 1" spacer, victor jr intake
Bowtie vortec 185cc head 2.00/1.55 valve 1.250 comp valve springs
JE 390 gram piston with low tension rings
45 lbs crank with 1.889 rods
248/252 @.050" .359"/.359" Lobe Lift 105 LSA Solid flat tappet
1 5/8-1 3/4 header, straight back exhaust with straight through muffler(3.5" dia)
Altitude 4,200 ft above sea level.

I like the combination. Things seem well matched.
The GMPP vortecs are good heads and will surprise you.

If they are un-ported and a 1.6 rocker is used, I'd say 475ish HP 450-460 TQ
I used those heads un ported on a 383 with a little bit smaller hyd roller and 11.4-1 comp and it made 525HP and 510 TQ.

If they are ported then it will depend on how well that was done.

Randy

[88bluestar]

Well it turns out it has the larger 371 vortec bowtie head which I gather is roughly 215 cc, maybe a bit less on the runners. The cam in it is a comp cams 4/7 ,252/256 @.050, .541 -.550 (1.5) at 108 lobe separation. We have a intake rule no more than 7" from top of block to carb base..540/.560 lift rule 7000 rpm pill
355 cid, 9.5:1 compression now that i had time to check it closer.

[F-BIRD'88]

The low cr and high altitude is really going to pinch the net result.

[MadBill]

It's not clear from your last note if the 9.5:1 CR is by choice or by rules . If by choice I'd target 11:1 or more for pump fuel and with race fuel maybe 13.5, if possible without too much hassle.

[88bluestar]

Bill, The rule is 9.5 max, as well as max 360 cid.