1jsmith

I recently put a 351w in my '67 and had it tested and tuned on the dyno. The problem is that I only have 230rwh and was looking for at least 300. I am about out of ideas on how to make 300, and I dont want to resort to nitrous, a Paxton, or a stroker kit (and I am also now low on cash). Any ideas?

-'74 351w, 30 over and freshly rebuilt
-Edelbrock Performer RPM heads, Performer RPM intake, and Performer 750 carb.
-Comp Cams .500 lift cam with 1.6 ratio roller rockers
-Speed Pro flat top pistons
-Hedman headers

MustangMadness7

ummmmm, theres something wrong. Youv got a 351 with new heads cam and intake with only 230whp? Thats way too low. Have you noticed any problems with it running or anything? I dont have experience with 351's, but a 302 with similiar mods will hit 280 or so whp, so a 351 should be higher than that.

92BOOSTED

Yes there is something way off.
Start with the basics, your tune.

Where is your timing set at?
What plugs are you using?
How much advance?
At what rpm is your full advance in?
How was the air fuel reading on the dyno?
What are specs of the cam and was it put in straight up?
What is your compression?
Are they roller rockers or pedestal mount?( i ask this one because the valves might be adjusted wrong).
every little bit of info helps because your engine according to what edlebrock put together with the same setup but with a lightning shortblock at 9.1 comp. made 409 hp and 411 ft lb. but they used the rpm cam shaft.
Ryan

924banger

i don't know how far off they are from the Lightning 351W, but Twisted Wedge heads seem to give out the most power. You could go all Lightning and have 240 stock power, throw onthe heads, injectors,bigger throttle body and spacer, and you should make 300 easy.....oh, just reread you post, you have carb so I don't know. If you want more info about Lightning 351's go to www.nloc.net. Some guys on there have done carb swaps.

1jsmith

Nope. It runs good and sounds good.

samseed101

What was your torque for your best run?

1jsmith

Okay, my timing, spark curve, and air/fuel were all adjusted on the dyno and I don't honestly remember what everything was set at. Lookingat my printouts from the dyno my spark curve is set at 12/32/42 if that helps. The guy at the dyno tested the timing at different stages and this came up with the best numbers. I really feel he did a good job. As far as my plugs they are NGK's (not sure of the model, but they aren't exotic). The cam is .493 intake, .500 exhaust- 218/224 duration at.050 with 110 degree separation. The compression is about 9.4 to 1. Comp Cams stud mount roller tip rockers (1.6 ratio). Does this help?

1jsmith

Best torque was about 282 with horsepower at just over 230.

samseed101

Hrm... those numbers do seem a little low. I know that the 1995 Cobra R 351w had 280 BHP, which isn't bad for stock. But they had 343 torque which is pretty damned impressive. Of course, those numbers were at the flywheel, but still... factor in the standard loss and you should still be seeing numbers higher than that.

I wouldn't expect you to get 300rwhp from your setup, but I would expect something better than 230. I would have expected something in the 250 - 260 range. I know those still seem lower than you want though.

Our of curiousity, how is your compression? How many miles ago was this rebuilt? I'm wodnering if you have a lot of blowby thats lowering compression. It may take a little time for those rings to settle in and that could explain some loss. Any chance you are losing some compression?

Also, what's your A/F ratio?

PONY GUY

something dont seem right to me I would check your basics like everyone mentioned