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Search found 2823 matches

by rfoll
Wed Feb 01, 2023 2:01 pm
Forum: Engine Tech
Topic: Cam gurus, I need advice
Replies: 51
Views: 2191

Re: Cam gurus, I need advice

It's got a scat "cast steel" crank it and I'm not sure what kind of rpm it can tolerate. I never minded turning a 327 or 350 up but the longer strokes kinda make me nervous. Also, I've never done it with a hydraulic cam, I've always ran solid flat tappet cams, this is my first hydraulic roller and ...
by rfoll
Tue Jan 31, 2023 5:25 pm
Forum: Engine Tech
Topic: Lowbuck Shop/Race Truck Build
Replies: 78
Views: 5428

Re: Lowbuck Shop/Race Truck Build

"so how would you build the 355?" Turn it into a 406. The first time a made the swap I found a full second and the mph to go with it. Of course, every time I build an engine I start thinking about the next one.
by rfoll
Fri Jan 27, 2023 11:22 am
Forum: Engine Tech
Topic: Selecting a compression ratio
Replies: 27
Views: 1193

Re: Selecting a compression ratio

The cylinder head and it's chamber design can dictate compression ratio. I have a 9.6:1 350 with Vortec heads that almost never pings on regular fuel. The predecessor with different heads pinged terrible at 9.3:1 and required retarded timing. I have no idea how the 300 chamber works. It might be use...
by rfoll
Mon Jan 23, 2023 1:13 pm
Forum: Engine Tech
Topic: Cam gurus, I need advice
Replies: 51
Views: 2191

Re: Cam gurus, I need advice

I didn't see anything about usage. A description of the car etc, but is it a daily driver, or a weekend warrior? Are you looking for best HP or drivability.
by rfoll
Mon Jan 23, 2023 12:20 pm
Forum: Engine Tech
Topic: retarding the cam from 4 degrees to straight up
Replies: 101
Views: 2916

Re: retarding the cam from 4 degrees to straight up

Fortunately for me the question got answered before it transformed, albeit relative, into a discussion on quench. But all told some of it has been enlightening. When we finally finish this motor and get it in the car I will re-visit this discussion and talk about how things work out. The plan is The...
by rfoll
Sun Jan 22, 2023 12:27 pm
Forum: Engine Tech
Topic: Lube for valve stems?
Replies: 55
Views: 20264

Re: Lube for valve stems?

I have had guides go bad, and when I asked my machinist he asked whether I used a liquid or paste as an assembly lube. They warranty the engines they sell and stopped using anything non-liquid years ago. He believes the heavier materials don't allow the oil to get past the thicker material. I use Be...
by rfoll
Mon Jan 16, 2023 8:56 pm
Forum: Engine Tech
Topic: retarding the cam from 4 degrees to straight up
Replies: 101
Views: 2916

Re: retarding the cam from 4 degrees to straight up

With IVC @ 63° the DCR is 8.3:1, about 192 CCP gauge psi, volume/pressure index is 457 (input is CCP × reduced stroke length, etc.). Guessing ratio of heats @ 1.25... Retarding it to 67° gives DCR is 8.05:1, about 185 CCP gauge psi, volume/pressure index is 420. Combustion pressure is down about 8%...
by rfoll
Mon Jan 16, 2023 5:31 pm
Forum: Engine Tech
Topic: retarding the cam from 4 degrees to straight up
Replies: 101
Views: 2916

Re: retarding the cam from 4 degrees to straight up

The engine won't get built while is play at the computer. It has been a good discussion.
by rfoll
Mon Jan 16, 2023 5:04 pm
Forum: Engine Tech
Topic: retarding the cam from 4 degrees to straight up
Replies: 101
Views: 2916

Re: retarding the cam from 4 degrees to straight up

For the discussion at hand it's a matter of how much is enough. The original question was about retarding the cam 4 degrees. It took 3 days and 2 pages to get an answer.
by rfoll
Mon Jan 16, 2023 3:16 pm
Forum: Engine Tech
Topic: retarding the cam from 4 degrees to straight up
Replies: 101
Views: 2916

Re: retarding the cam from 4 degrees to straight up

In regards to the dished piston discussion, there is a world of difference in the types. The Vortec piston has a nice 1/2" flat at the perimeter. I'ts predecessor had a big chamfer to reduce crevice volume for emissions. The Vortec piston will tolerate much more timing without issue, and the chamfer...
by rfoll
Sun Jan 15, 2023 8:32 pm
Forum: Engine Tech
Topic: retarding the cam from 4 degrees to straight up
Replies: 101
Views: 2916

Re: retarding the cam from 4 degrees to straight up

Debate all you want, I told you what to do. It'll work. I've done it 50 times since the mid 90's. But listen to guys with "opinions ". Good luck, hope it works out for you. 👍. Quench works the opposite of what everyone on here thinks. Making it "tighter" isn't better or more "efficient" because it ...
by rfoll
Sun Jan 15, 2023 6:15 pm
Forum: Engine Tech
Topic: retarding the cam from 4 degrees to straight up
Replies: 101
Views: 2916

Re: retarding the cam from 4 degrees to straight up

rfoll wrote: Sun Jan 15, 2023 6:14 pm We will likely spring for the gaskets, The 2 piece timing cover allows for changing valve timing if needed. Thanks for all of the replies, Rick.
by rfoll
Sun Jan 15, 2023 6:14 pm
Forum: Engine Tech
Topic: retarding the cam from 4 degrees to straight up
Replies: 101
Views: 2916

Re: retarding the cam from 4 degrees to straight up

We will likely spring for the gaskets, The valve timing can be tried if needed. Thanks for all of the replies, Rick.
by rfoll
Sun Jan 15, 2023 1:57 pm
Forum: Engine Tech
Topic: retarding the cam from 4 degrees to straight up
Replies: 101
Views: 2916

Re: retarding the cam from 4 degrees to straight up

Would you do it? We have a 2 piece timing cover and can retard it later if necessary.
by rfoll
Sun Jan 15, 2023 1:43 pm
Forum: Engine Tech
Topic: retarding the cam from 4 degrees to straight up
Replies: 101
Views: 2916

Re: retarding the cam from 4 degrees to straight up

Retarding the cam 4 degrees from 64 to 68 will reduce your cranking compression about 8.5 psi. Stan Is that enough to make it less sensitive to pinging? I'd run a .051thick gasket. That will work better, I promise. It actually works the opposite of what most believe. What elevation are you at in Or...