# Engine Horse Power



## Baaad65 (Aug 29, 2019)

So Pontiac Jim suggested this game and thought it would be interesting and I would like feedback from the experts, so here's my build that I bought second hand. It's a Butler 461, '72 block, 7K heads, just about 9.5 compression.


----------



## Baaad65 (Aug 29, 2019)

Sorry forgot to include it had a Cliff Ruggles carb not sure what size, just says original 400,4 spd carb.


----------



## Old Man Taylor (May 9, 2011)

That looks like a great street engine with lots of grunt.


----------



## Baaad65 (Aug 29, 2019)

I have the dyno numbers, any guess's anyone ?


----------



## Sick467 (Oct 29, 2019)

Was it dyno'd without exhaust? Did I miss what was being used for exhaust...headers or mani's?

Assuming headers and HP at the flywheel...490 hp / 505 ftlb


----------



## Baaad65 (Aug 29, 2019)

I'm assuming Butler dynode it with headers?


----------



## PontiacJim (Dec 29, 2012)

510HP 530TQ


----------



## Baaad65 (Aug 29, 2019)

Ok here's the dyno results


----------



## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Ok here's the dyno results
> View attachment 142351


Nice. I got close on the TQ. I thought more HP only due to the roller cam as it seems these seem to ramp up HP more so than a flat tappet cam.

Head flow may also have been a restriction that can have a limiting factor on HP. I like the TQ numbers.


----------



## Old Man Taylor (May 9, 2011)

As you said, small cam and stock head flow.


----------



## Old Man Taylor (May 9, 2011)

But as I said, look at the "grunt" - 527 ft-lbs at 3200 RPM.


----------



## Baaad65 (Aug 29, 2019)

Ok so this is what I'm curious about from you guys that are way smarter than me, I made some changes to squeeze some more power out of it and hopefully didn't waste my money. First I swapped the stock intake to an Edelbrock Performer RPM, then swapped the carb after a mistakenly trying a 770 street avenger vac secondary I now have a 850 QFT dp that's been modified with a 1/2" spacer, next swapped in Scorpion 1.65 Race rockers, I put one step cooler Iridium plugs so I could run my intial timing at 19° and there's no vacuum advance, I'm also running the 2.5 outlet exhaust manifolds from Butler. So what do you think I gained if anything.


----------



## Baaad65 (Aug 29, 2019)

Here's the carb specs..it does feel a little better.


----------



## Old Man Taylor (May 9, 2011)

All of those should help, but I'm concerned about your initial timing. You have iron heads with 9.5:1 compression. 19 degrees is A LOT unless the distributor has some kind of limitation. I think 36 degrees total would be pushing it.


----------



## Baaad65 (Aug 29, 2019)

Ok, Butler told me 14-16° initial and 34-36° tot @ 2500 so does that sound right with my changes, and I always run 93 octane. Just thought with the cooler plug and richer carb I could get away with some more advance but I don't want to damage anything.


----------



## Baaad65 (Aug 29, 2019)

Here's how the distributor is set up, from Butler.


----------



## Old Man Taylor (May 9, 2011)

Baaad65 said:


> Ok, Butler told me 14-16° initial and 34-36° tot @ 2500 so does that sound right with my changes, and I always run 93 octane. Just thought with the cooler plug and richer carb I could get away with some more advance but I don't want to damage anything.


I would leave it alone, it looks perfect. I am also not a believer in a colder plug. I've never had good luck with them. I always run the R45S - as long as they are available.


----------



## Baaad65 (Aug 29, 2019)

Good to know, was just trying to keep any detonation away if I wanted to run more timing, so what do you think back the initial down to 16° ? Any other suggestions to squeeze out some horses for cheap? Also want to get it to the track this year to see what it's got so looking at everything what do you think a good shift point is and a redline on this motor, I have the lights coming on at 5700 rpm and rev limiter set at 6200.


----------



## Old Man Taylor (May 9, 2011)

That's all I would do is put it back to 16. As to shift point, I would start at 5700 and work up to 6000. It looks like you have the parts to go 6000 or over, put check with the Butler's to be sure.


----------



## Baaad65 (Aug 29, 2019)

Ok, I was thinking you shift it at the max horse power on the dyno chart but maybe now it's higher with the changes I made? So you think it's good for over 6000 ? Because I don't know to break anything. Any harm leaving the plugs I have in if they're staying clean? What do you think the horse power is now with my changes?


----------



## Sick467 (Oct 29, 2019)

You are certainly getting beyond my experience level with squeezing horses out. Your additions have made a difference in the right direction. Without flow testing the intake, heads, and exhaust mani's...it's hard to say if the new intake did much. I'd say it did some as a guess, maybe not noticeable by the seat of your pants all by itself. Jumping the rocker ratio up has helped the flow only if the exhaust mani's can take it. I am not studied up on the 2.5 mani's and am interested in how they compare to headers as I will be looking to these mani's for my 67 project. The biggest factor would be the new carb IMO...if the motor can use it and I would think it could. 

Bottom line is...If you can feel a power increase by driving the car...you have added at least 20hp. Anything below that and I would be saying " I THINK I can tell a difference", but 20-30 HP should be more than "I think I can feel it".

I can't help with the redline...that's all you! (for obvious reasons). I don't race my motors for that last fraction of a second, so I keep redline in a safe place. My naïve interpretation of the dyno sheet tells me that more HP could be gained beyond 5500, but they did not go there and I would not either. But, racing does require pushing the limits and the cost associated with that can only be experienced by trying. I am curious if further dyno testing, once in the car, can help to determine redline?


----------



## Baaad65 (Aug 29, 2019)

Thanks for the input, what I've read on the exhaust manifolds is their isn't much of a difference from headers on motors like mine I'm sure they wouldn't do you good with huge flowing heads on a 600+ hp motor but there's no way I'm fighting with headers did that once, road clearance problems, rag joint interference...these were nice to work with. I'm happy with the power plenty to get in trouble with especially before the drag radials that was scary, it's a show and go car but I just want to see what it would do at the track once for bragging and to display the read out if it's a good one at shows you know an ego thing ha ha, I would be happy with anything under 12 so I can call it an 11 second car but I've never raced before so it ought to be interesting...who knows maybe I'll get the bug and want to do more


----------



## Old Man Taylor (May 9, 2011)

First confirm what the Butler's think is a safe max RPM for your engine. If you've never raced before then I would shift the first run at 5000. You'll have too many things to pay attention to. It does look like your HP flattened out at 5500. Assuming that's the peak, I go with 200 over peak HP. But you need to determine this yourself for your combination.


----------



## Old Man Taylor (May 9, 2011)

What transmission are you running?


----------



## Baaad65 (Aug 29, 2019)

Thanks for the tips, ya last thing I want to do is break anything that would be bad. It's called an M23Z 4 speed custom built and beefed up with a 2.98 first gear 26 spline output, McLeod super street pro clutch, Strange drive shaft forged yokes, 12 bolt rear 3.42 gear w/the larger forged yoke, Eaton purple spring posi, Strange axles, SSM lift bars, the round triangulation bars, semi boxed upper arms, stock springs, KYB gas adjust shocks and a 1" sway bar, 10" drag radials. If you had a crystal ball and if I hooked up and cut a good light...those are big if's what kind of times do you think this set up is capable of?


----------



## Old Man Taylor (May 9, 2011)

I think you will find that the drag radials don't work well on a car with a standard transmission. They hook up great until they don't. Once they start spinning they don't want to recover. At least mine didn't.


----------



## Baaad65 (Aug 29, 2019)

Good to know, I needed something I could drive around so it was a good compromise and the radials were dangerous when I would get on it...maybe I'll burn them up at the track then I'll have a good excuse to switch to 17" wheels that I would like


----------

