Expected tire spin 426-S

[steve340]

Recently I watched a video posted on Youtube by Richard Holdener. He is quite well known and I believe the info in the test would be accurate.
It was also pretty interesting with were some modifications can cost you.
He took a junk yard 460 Ford big block and put it on the dyno. It was a 1968 motor so he said it was about 10:1 compression. If was fitted with the factory iron 4 barrel manifold.
He used a 750 Holley carb and long tube headers and this was the baseline.
He then swapped on a Weiand dual plane manifold.
The motor lost 35 ft/lbs of torque and it did not match the factory manifold until 3500 rpm.
Although the manifold did make more torque eventually it shifted the RPM of the peak torque way up also.
May be some of reason you are looking to make some changes to get that snap of idle.

 

[Nate S]

Recently I watched a video posted on Youtube by Richard Holdener. He is quite well known and I believe the info in the test would be accurate.
It was also pretty interesting with were some modifications can cost you.
He took a junk yard 460 Ford big block and put it on the dyno. It was a 1968 motor so he said it was about 10:1 compression. If was fitted with the factory iron 4 barrel manifold.
He used a 750 Holley carb and long tube headers and this was the baseline.
He then swapped on a Weiand dual plane manifold.
The motor lost 35 ft/lbs of torque and it did not match the factory manifold until 3500 rpm.
Although the manifold did make more torque eventually it shifted the RPM of the peak torque way up also.
May be some of reason you are looking to make some changes to get that snap of idle.

Good thinking! Just went and dug up a hot rod article where they compared several 440 intakes. Comment on this one: “ The numbers showed a substantial improvement compared to the stocker over most of the range tested, particularly higher up in the range. Interestingly, peak horsepower occurred very high in the rpm range with the CH4B, equaled only by the new Victor. It tended to favor higher rpm performance and was kind of soft at the bottom of the range. The averages were quite good among the other two planes, well ahead of the stocker. No wonder people remember this as a good intake.”

I’ll keep that in mind when I advance the cam. I’ve got a stock intake right here, only challenge is the Holley fuel line. So cam first, then intake. I used these 30 ish years ago and don’t remember many downsides.

 

[steve340]

From what you have found that manifold probably does need a higher stall converter.
As you say cam then manifold and you may not need to do the converter.
There is some blending you can do to a stock manifold that is fairly effective and is real easy to do if you go that way.

 

[R413]

I don’t believe that intake affects BB mopars the same way as the Ford magic. I had an all stock 440 HP with the CH4B and 12” converter and it ran great.

I’ve spent years at the drags. Friends with ford guys and they had a 351C and they said the same thing with a performer intake, it really slowed it down. Same as your 460 ford story.

 

[Nate S]

Update. Instead of my magic marker and tape measure on the harmonic balancer I took it apart and used a proper degree wheel after confirming TDC. Intake CL 114.5, intake .050 -10.

interestingly, if you look up this cam it’s made by several different outfits. Melling CL = 111, intake .050 = -6, crane cL = 110 intake .050 = -5, some places it’s stated at 113 but that’s just dividing open and closed/2 and it’s an asymmetrical lobe. Going for 110. Will go back together tomorrow night.

 

[steve340]

Interested to hear what difference the cam timing shift makes.
I assume any manifold changes will come later?

 

[Nate S]

Interested to hear what difference the cam timing shift makes.
I assume any manifold changes will come later?

Yeah, intake only if I have to. Had a ‘70 Coronet R/T with this intake and a Holley 830 annular discharge and it ripped down low. That was with a MP 280/474 a 4 speed and a 3.54 Dana.

 

[Don Frelier]

It's not the intake.

 

[66Satellite47]

Changing cam timing should help, if you're at 114.5, I'd get to at least 110, maybe 108. I found it takes 4* to really see the difference. As far as intakes, a CH4B would be worth a bit, especially at the higher RPM. A quality 10" converter will amaze you. There is no valid comparison between the Ford motors & Mopar 440, totally different design concepts, especially the Cleveland style, or long stroke 460.

 

[Nate S]

So the bushing kit had two of the same advance. No 4 but two 6. Put in a six and the new CL is 109. Notably nicer to drive, better idle. Can feel less pull at the top of first but not bad. Still no tire frying off the line but the advanced cam wants a bigger squirter nozzle. A little hesitation now from a dead stop. Getting there. Certainly the right thing to do. Now to tweak the carb.

 

[Frustration]

I just read through this whole thread. I think that the car is set up reasonably well where it is right now, at least for the engine. 3.23 gears, a tight converter, and low compression are not helping you. If you could add 3/4-1 full point (gaskets??) of compression, the car would likely respond well. Even before doing that, I'd install either different rear gears (3.91?) and a looser converter. I used to run the CH4B in my road runner with a Comp Cams Hydraulic Flat Tappet Cam of .501 lift. With 3.91 gears, a 3500 RPM converter of unknown manufacturer, and 9.5:1, the car would run 13.30's through the exhaust (not the setup in the below photo). It went into the high 12.70's with the pipes open. Your issue seems to be getting the engine into it's happy rpm range. The converter is what will do that for you. The gear change just makes it happen faster.

Changing gears to a numerically higher set would really wake your car up. I understand that everyone doesn't want drag strip gears, but the road runner I mentioned above was purchased new by my gf. He did not have another car. Drove it for 250,000 miles before the engine failed. That was all done with 3.91 gears. That gear set is now in our '64 Fury Convertible...that uses a CH4B and a Carter 750. That car is a 4-speed. Good luck. Borrow a set of gears from a buddy and have fun!

 

[Nate S]

I just read through this whole thread. I think that the car is set up reasonably well where it is right now, at least for the engine. 3.23 gears, a tight converter, and low compression are not helping you. If you could add 3/4-1 full point (gaskets??) of compression, the car would likely respond well. Even before doing that, I'd install either different rear gears (3.91?) and a looser converter. I used to run the CH4B in my road runner with a Comp Cams Hydraulic Flat Tappet Cam of .501 lift. With 3.91 gears, a 3500 RPM converter of unknown manufacturer, and 9.5:1, the car would run 13.30's through the exhaust (not the setup in the below photo). It went into the high 12.70's with the pipes open. Your issue seems to be getting the engine into it's happy rpm range. The converter is what will do that for you. The gear change just makes it happen faster.

Changing gears to a numerically higher set would really wake your car up. I understand that everyone doesn't want drag strip gears, but the road runner I mentioned above was purchased new by my gf. He did not have another car. Drove it for 250,000 miles before the engine failed. That was all done with 3.91 gears. That gear set is now in our '64 Fury Convertible...that uses a CH4B and a Carter 750. That car is a 4-speed. Good luck. Borrow a set of gears from a buddy and have fun!View attachment 947437 View attachment 947440

I appreciate the thoughtful reply. I think you’re right about the RPM range. Certainly right about the gears. As for the compression, interestingly the factory 10.1:1 actually measured and cc’d out to 9.75 in this case, I’m not too far off with 9.25. I still have the old heads, 516’s though so I’d give up the 1.74 exhaust valves and hardened seats, now that it’s been decked I’d get about 9.9:1, probably not worth the effort for what I’d give up.

Back 25-35 years ago I had many cars like this. The 3.91s are great, certainly would help in many ways, I remember the disappointment of switching to 3.54s. I’m not really out to crush it on acceleration at the moment. In fact it goes pretty well, just not the way I remember off the line. In particular I remember a ‘68 charger R/T, 727, stock, 3.23s that would vaporize the tires by just stuffing the gas. Also had a ‘67 charger, same combo, same result.

Advancing the cam helped, enough so that now I see a carburetor based pause. Fixing that shortly (accel nozzle). There was a Chrysler service bulletin about torqueflites back about ‘73 where they were explicit about the stall speeds. (See attachment). I bought a tach but have been busy so I haven’t put it in yet. I’m interested to see where this winds up, I have a distinct sense it’s low. Engine is nice and healthy though, just trying to tease out the correct expected behavior.

I’ll post more results as I have them.