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Search found 946 matches

by piston guy
Fri Jun 04, 2021 10:40 am
Forum: Engine Tech
Topic: Press Pins and Balance
Replies: 16
Views: 751

Re: Press Pins and Balance

I have an older "shadow graph" style holding fixture. I can weigh the rod and piston assembly together and come up with a bob weight.
by piston guy
Tue Jun 01, 2021 10:36 am
Forum: Engine Tech
Topic: 4781/850 DP jetting.
Replies: 16
Views: 731

Re: 4781/850 DP jetting.

I ran a 4781 on my Boss 302 engines and it liked 80 in the front and 88 in the rear with the power valve blocked. It was faster than the 4780 in "my" application. Still have it 40 years later.
by piston guy
Fri May 14, 2021 2:58 pm
Forum: Other - For Sale or Wanted
Topic: Racing Engine Preparation by Waddell Wilson
Replies: 2
Views: 150

Re: Racing Engine Preparation by Waddell Wilson

Ben ,
I do have a pristine copy I can part with. PM me your address information and we'll work something out.
by piston guy
Tue May 04, 2021 4:24 pm
Forum: Engine Tech
Topic: piston weight
Replies: 81
Views: 7824

Re: piston weight

No, cracking was due to them not designing the piston properly to handle the rpm in the first place The white paper was toilet paper, used to clean up the mess on the ground after another engineering disaster.. Usually due to inadequate wall thickness on the wrist pins. Being the simplist part to d...
by piston guy
Tue Apr 27, 2021 1:00 pm
Forum: Engine Tech
Topic: piston weight
Replies: 81
Views: 7824

Re: piston weight

There is a good Honda white paper from their V8 F1 engine about piston design, and them cracking due to the rpm’s they were running at the time. No, cracking was due to them not designing the piston properly to handle the rpm in the first place The white paper was toilet paper, used to clean up the...
by piston guy
Fri Feb 19, 2021 4:20 pm
Forum: Engine Tech
Topic: Shelf life of unopened synthetic "racing" engine oil?
Replies: 51
Views: 1825

Re: Shelf life of unopened synthetic "racing" engine oil?

I must have bullet proof oil pans last failure was 35 years ago.
by piston guy
Fri Feb 19, 2021 11:12 am
Forum: Engine Tech
Topic: Shelf life of unopened synthetic "racing" engine oil?
Replies: 51
Views: 1825

Re: Shelf life of unopened synthetic "racing" engine oil?

I still have a case of Kendall GT1 in cardboard cans. Hell yes I am going to use it! Next time I change oil in the race engine. Sealed cans are just that. I can see a plastic bottle being different but I have a couple cases of those too.
by piston guy
Fri Feb 12, 2021 1:59 pm
Forum: Engine Tech
Topic: Modification advice for 331 Ford
Replies: 68
Views: 2935

Re: Modification advice for 331 Ford

Tracy. The rod to stroke ratio is 1.586 nearly the same as a 5.4 rod 347. @ 1.588. The biggest issue is how far it pulls out of the bottom of the block but after 14+ years of operation it must be OK. Go to the AFR aluminum head for sure. Your 282S cam ( before the 1.7 ratio rockers) is slightly more...
by piston guy
Mon Feb 08, 2021 3:40 pm
Forum: Engine Tech
Topic: Quench vs Compression increases
Replies: 24
Views: 1229

Re: Quench vs Compression increases

There are a couple of important things to note here. (1)The "most" likely combination to detonate is a factory iron head with a ( now) 50+ year old chamber design. "Modern" aluminum heads like your AFRs are vastly different in chamber shape and being aluminum are usually safe to 10.7 on 91 octane we...
by piston guy
Mon Feb 01, 2021 2:02 pm
Forum: Engine Tech
Topic: Piston Dish limits
Replies: 21
Views: 920

Re: Piston Dish limits

Gordon, There are custom piston manufacturers that will make you a -32cc dish piston in 4032 alloy for your Cad. At that volume , "I" would recommend a round dish with a specific width "squish band". I was the first one to "adapt" the conical ( first) and spherical ( later for more volume less depth...
by piston guy
Thu Jan 14, 2021 11:15 am
Forum: Engine Tech
Topic: Flat Tappet vs Roller Specs
Replies: 36
Views: 1731

Re: Flat Tappet vs Roller Specs

Mike ,
.842 flat lifter still "around".0025/degree? It was when I was at Erson's in the '70s.
by piston guy
Wed Jan 13, 2021 12:39 pm
Forum: Engine Tech
Topic: Flat Tappet vs Roller Specs
Replies: 36
Views: 1731

Re: Flat Tappet vs Roller Specs

"To me" , when given a flat tappet and roller with the same "at .050" durations , the roller will run like a flat tappet with 8-10 more degrees of duration.
by piston guy
Fri Jan 08, 2021 12:08 pm
Forum: Engine Tech
Topic: Piston Design Questions
Replies: 38
Views: 1426

Re: Piston Design Questions

Detonation is FAR more common with iron heads , we all agree. "I" don't like to increase piston to head clearance beyond .040 with iron heads because of that. Custom pistons from some piston manufacturers "can" be as little as $100 extra and worth every penny.
by piston guy
Thu Dec 31, 2020 3:26 pm
Forum: Engine Tech
Topic: Crankshaft balancing vs RPM
Replies: 15
Views: 1359

Re: Crankshaft balancing vs RPM

"Balancing" a rotating AND reciprocating engine has always and will always be a compromise. Add to it the variables in cylinder pressures between cylinders and the torsional capabilities of the given crankshaft/material and connecting rod material and it becomes an even bigger challenge, Then you ha...
by piston guy
Mon Dec 28, 2020 2:25 pm
Forum: Engine Tech
Topic: 451ci Windsor Arias Hemi
Replies: 4
Views: 634

Re: 451ci Windsor Arias Hemi

Crower ground me a cam for my "chris cross" 351C heads where the exhaust lobe ran the intake rocker and vice versa. They should be able to do a cam. Arias probably used a Howards from Bobby Johansen.