Got my car on the dyno for tuning today. First pull they had to shut down at around 3800 rpm due to ping, had 54 degrees advance. HP was at 237 and Torque at 326. Its a 71 350. Their plan is to eliminate vacuum advance and tune the dist. with weights only.

 

Were those the numbers at 3800 rpm? If so, it looks like it will be pretty nice when it is running right.

 

Those were what the numbers appeared to be, to me, in looking at the screen.

 

Shut it down at 4800 rpm, running too lean. HP was 275 Tq was 330.

 

Tuner says he's done. 11 degree initial timing 29 total (says any more and it pings bad, 91 octane with additive). Hp at 285 tq at 338. A/F ratio is good through out the rpm range.

 

Is that a stock 350 or did you add some goodies to it?

 

yea goodies, was thinking it should have broke 300. He wants to give it more timing but it's pinging.

 

did you have the valves cut?

 

#7 heads with 2.07 / 1.6 . Rebuilt before I got it.

 

Would like to learn more. Why is it pinging at only 29 degrees of advance?

 

Pump gas, close to 10:1 cr, iron heads...dunno exactly. Guess I start my research why?

 

What cam is in it? I have learned that with that cr and a cam that the intake closes too soon will give you a really high dynamic cr.

 

Are you sure your balancer is correct? If you're getting pinging at 29 degrees you have some thing wrong inside. The cast iron heads have a rough casting in the chambers. I hope you smoothed them out and took out all potential sharp edges. I have EFI but I run 36 degrees at WOT and 44 at cruise on 89 octane with 9.7 to 1! In Florida! No problem! I didn't have much cam either. Hope you sort it put. Keep us posted.

 

I got the car today and the final results are 11.5 initial 31.5 total. 281 HP...338 Torque. Torque curve flat from 2500rpm to 5000.

 

Would you mind telling what your A/F ratios were? The reason I ask is, I'm using the original point style ignition and the A/F readings were around 8 and 9ish. The fellow who rebuilt the engine claims that the HEI system would get it back up to a more reasonable range.Looking for advice.

 

Bunser- there's no ignition system in the world that will make that much of a difference. You'll have to rejet the carb, a bunch. At this point I'd have to question the level of knowledge of your engine builder.

 

Bunser, I dont have the sheets with me but my A/F ratio was pretty close to optimum. 13-15 somewhere in there. I agree you need jetting. My guy had mine apart 4-5 times for primary jets and secondary rods.

 

I too have to think that a high energy system is not the proper solution.The engine has been completely rebuilt top to bottom and the carb was "overhauled" and refinished.
The engine is from a W31, 1970 vintage with the original carb.He did change out the original secondary rods and hanger.The primaries of course have no metering rods and I don't think the jets are replaceable.I'm open to any more suggestions as I know there are a lot of knowledgeable members on here.

 

I entered 281 hp into a 1/4 mile formula with a car weighing 3600 and got a time of 14.36. I had a 68 W30 years ago that ran a best of 13.93 on a near perfect run. I would say your motor will perform well and you'll be happy. Keep looking for issues but I got a feeling your close to max now. My 360 hp 400 calculated to be around 325hp.
Sounds like a great motor to me.

 

The jets are these slotted brass pieces, and are numbered.
They unscrew with a flathead screwdriver.

They used to sell little threaded boards at the store when I was a kid that you could screw your extra jets into.



Here's another.

 

My apologies Norm, i didn't intend to hijack the thread.

 

The correct response would have been, a link to your new thread:

https://classicoldsmobile.com/forums...-problems.html

Norm

 

What did the dyno pulls and tuning cost?

 

The bill was $540.00

 

I forgot all about this thread. Glad you got it pretty well tuned.
I think that combo has more in it though.

 

Ouch on the $540!