Newby 429-460 question

[OregonHighboy]

Hi,
Great forum here so I thought I would post a question about my new to me '79 F-250 4x4. I bought it to tow an 8,000lb boat and trailer (wt??) from N.CA to N.WA, plus I,ve always kinda wanted a '70's era Ford "custom" 4x4. It did the trick, but when I bought it I was told, like apparently so many people, that it had a '70 Police Interceptor engine. I have receipts for all the work done on it and was wondering if I could get some help interpreting it.

It shows a 1970 429 bored .30 over; Mooly rings, balanced; Crank .010-.010; Cam 262-272;, 479-504 lift, etc. It appears to have been rebuilt, was mated with a C6 auto, this was about ten years and 11,000mi before I bought it and it runs great, except that it does not want to shut off right away and there is some minor valve chatter when I get on at certain RPMs.

Anybody know what the engine might actually be, and what kinda HP/Torque its putting out? I think I saw a D1VE on the block and C 8Ve-E on the heads.

Any help from the experts here is appreciated!

[techinspector1]

it does not want to shut off right away and there is some minor valve chatter when I get on at certain RPMs.

Running on after shutting off the ignition is called "dieseling". Here's one of the best write-ups I've seen explaining it.....
http://mgaguru.com/mgtech/engine/ro101.htm
I used to give my motors a "water tune-up" once in a while. Take one gallon of water and the truck out of town where there are few other people to complain. Take a buddy with you. Remove the air filter. Fire the motor and have your buddy modulate the throttle in Park or neutral with foot on brake while you pour a small stream of water down the carburetor, alternating side to side into the primaries. The water will try to kill the motor, so your buddy will have to keep up by giving more throttle to keep the motor from dieing. After a couple of tries, you'll get the knack of how much water to pour. You won't believe the crud that comes out of the tailpipe(s) during this operation. That's why you don't want to do it near any populated areas. The water is steam-cleaning the combustion chambers and getting rid of the carbon buildup that is the probable cause of the dieseling.

Dieseling was quite a problem with the early to mid 70's motors as Detroit was forced to lower static compression ratios, retard camshafts and raise engine operating temps. I remember an anti-dieseling solenoid mounted on quite a few of the GM cars I drove in that period. It was a solenoid that when activated, allowed the primary throttle blades to open to the idle position. When the key was shut off, the dashpot relaxed and pulled the throttle blades completely closed so that no mixture could pass into the motor, thus, no run-on.

The valve chatter you hear is more than likely muffled detonation. It's the same thing as hitting the crown of the piston with a sledge hammer. Here's a pretty good explanation....
http://www.misterfixit.com/deton.htm
Not mentioned in the article is water injection. It provides a fix for motors that were built with too much static compression ratio for the available fuel without having to tear into the motor to change components. I have made a simple and effective water injection unit from an old Ford windshield washer bag with the little motor/pump in it. Run a line to the carb and terminate the line with an old carb jet (drill a blank one) drilled to about 0.030" and using a microswitch to operate the pump at about 1/2 throttle or more. Of course, there are commercial water injection units available at the cost of hundreds of dollars. You can add up to 50% methanol, ethanol or isopropanol to the water to gain back a little energy and aid cooling the mixture further.

If I had to guess what is going on in your motor, it is probably either or both of these....
1. Static compression ratio too high with not enough cam to bleed off excessive cylinder pressure. Using what you perceive as the proper ignition timing probably isn't helping any either.
2. Piston used in rebuild was short compression height, leading to excessive piston deck height and lack of squish. Squish "jets" a part of the fuel/air mixture from the coldest side of the chamber over into the spark plug area when the piston is coming up to TDC on compression. This homogenization and turbulence of the mixture allows a higher static compression ratio engine to operate on lesser fuels which might be the best available at the pump. (Think 11.0:1 on 91 octane fuel as a for-instance)

[hotrodstude]

totly agree with tech.i've always used water injection with all of my hi-compression street engines have had real good luck with it.

[Daffy427]

Stock compression ratio on those is like 10.7 to 1. Gonna be hard to find gas it's gonna like.

[OregonHighboy]

Wow! Thanks for that Techinspector1! Response was more that I could have hoped for for sure!!
Any recomendations on what fuel to use after I get it cleaned out? I''ll look into the water injection as well.

Any guesses on the HP/Torque output?

Thanks again!

[techinspector1]

I think I saw a D1VE on the block and C 8Ve-E on the heads.

D1VE would be the code for a 1971 block, C8VE would be the code for heads that were first cast in 1968. The E suffix would indicate that this is the 5th change in the heads. "A" would have been the first change. These are great heads, although they are small combustion chamber models. Back when they were being produced by the factory, Sunoco 260 racing gasoline was available at the pump at most every corner service station, so running 11.0:1 on the street was no big deal.

There are too many variables to estimate the power of your motor.

[OregonHighboy]

Interesting . . . Thanks! Just out of curiosity; What do the numbers in compression ratio 11.0:1 mean?

[Paul Kane]

Hi,
Great forum here so I thought I would post a question about my new to me '79 F-250 4x4. I bought it to tow an 8,000lb boat and trailer (wt??) from N.CA to N.WA, plus I,ve always kinda wanted a '70's era Ford "custom" 4x4. It did the trick, but when I bought it I was told that it had a '70 Police Interceptor engine. I have receipts for all the work done on it and was wondering if I could get some help interpreting it.

It shows a 1970 429 bored .30 over; Moly rings, balanced; Crank .010-.010; Cam 262-272;, 479-504 lift, etc.

Anybody know what the engine might actually be, and what kinda HP/Torque its putting out? I think I saw a D1VE on the block and C 8Ve-E on the heads.

Any help from the experts here is appreciated!

You do not have a 1970 439 Police Interceptor engine. The 429 Police Interceptor engine did not come out until 1971 and uses a different block casting number and different head casting number. The 1970 engine was a 428FE PI engine and is a completely different engine family.

Your heads are from a 1968 production 429 or 460 and the block is from a 1971-1978 429 or 460. Compression ratio is likely between 9.5:1 and 11.5:1 but we can't know for sure without a piston part number.

Paul

[OregonHighboy]

If I had to guess what is going on in your motor, it is probably either or both of these....
1. Static compression ratio too high with not enough cam to bleed off excessive cylinder pressure. Using what you perceive as the proper ignition timing probably isn't helping any either.
2. Piston used in rebuild was short compression height, leading to excessive piston deck height and lack of squish. Squish "jets" a part of the fuel/air mixture from the coldest side of the chamber over into the spark plug area when the piston is coming up to TDC on compression. This homogenization and turbulence of the mixture allows a higher static compression ratio engine to operate on lesser fuels which might be the best available at the pump. (Think 11.0:1 on 91 octane fuel as a for-instance)


Using higher octane fuel and no longer having the two issues I described, better mileage too. Thanks again!

[bluvelle65]

BTW... Welcome to CHR fellow Northwestener!!!

[OregonHighboy]

Thanks Bluvelle! I actually spend a lot of time up in the Anacortes area too, not too far from Everett. Beautiful area!