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Marv D · 11-07-2010, 11:49 AM

Wow, this has became a great conversation on valve train tech,, sorry for dragging things so far off topic, but some really great info and thoughts here.

Jays comment was referring to the standard 23° Gen-1 SBC with a retro-fit hydraulic rollers and a reduced base circle cam. We already had a set of Crower retro-fit hydraulic rollers for one of his short duration large lift cams. Was looking for a 1.55" spring to keep it all in check without a rev kit. Why he suggested 400 pounds on the nose?? I honestly haven't a clue. Possibly that is where he felt the lifters would start to have excessive bleed down, axle fatigue, total collapse,,,, really don't know. Sounded like a good number to me as most every spring I found for a hydraulic are on the 130ish# seat pressure and 280-350ish at .6 for hydraulic cams. Figured there had to be some solid thought behind it and really just never questioned it.

c-10simplex.. let me offer something my machinist explained to me a long time ago.

An engine 'builder' takes boxes of parts and pieces, inspects, and machines as necessary to make every component fit with the proper tolerance and clearance.

An engine 'assembler' can take the motor the 'builder' created and take it all apart, replace soft parts and re-assemble.

This is what Super is getting at. 'BUILDING' a new motor from boxes of parts takes a 'builder' . You may get parts that are called' ready to bolt on' but never trust it till you yourself have disassembled, inspected, measured, and checked that it fit's 'RIGHT' .

Theoretically, the Slummit stroker blocks are ready to start dropping rotating 'assemblies' in and make a motor. But in the end,, it's YOUR responsibility to see that it all goes together right.

Especially with a stroker, nothing will EVER be a bolt together. Heck even changing the cam timing will change rod to cam clearance. If you use a cap-screw rod vs a standard GM I-beam rod you will have VERY difference clearance to the bottom of the bores, pan rail and block face. No way can they make a 'one block fit's all' offering. Too many variables. The tolerances such as the thrust surface, journal size, all SHOULD' be on spec and a bolt together. But especially wit the Eagle junk that is finish machined in China,, you better check even that. I have Eagle 4" stroke crank that was + .0007 on the rods, and - on the mains. RIGHT OUT OF THE BOX. You can never just 'trust' anything any more. And ultimately,, who is going to loose here if you don't? They may replace a bad crank, but they aren't going to replace the other parts that get destroyed when it all goes south.

11-07-2010, 11:49 AM	#15
Marv D Registered Truck Offender Join Date: May 2008 Location: hells training ground (aka Ariz) Posts: 3,118	Re: Tell me about your 383 Stroker engines Wow, this has became a great conversation on valve train tech,, sorry for dragging things so far off topic, but some really great info and thoughts here. Jays comment was referring to the standard 23° Gen-1 SBC with a retro-fit hydraulic rollers and a reduced base circle cam. We already had a set of Crower retro-fit hydraulic rollers for one of his short duration large lift cams. Was looking for a 1.55" spring to keep it all in check without a rev kit. Why he suggested 400 pounds on the nose?? I honestly haven't a clue. Possibly that is where he felt the lifters would start to have excessive bleed down, axle fatigue, total collapse,,,, really don't know. Sounded like a good number to me as most every spring I found for a hydraulic are on the 130ish# seat pressure and 280-350ish at .6 for hydraulic cams. Figured there had to be some solid thought behind it and really just never questioned it. c-10simplex.. let me offer something my machinist explained to me a long time ago. An engine 'builder' takes boxes of parts and pieces, inspects, and machines as necessary to make every component fit with the proper tolerance and clearance. An engine 'assembler' can take the motor the 'builder' created and take it all apart, replace soft parts and re-assemble. This is what Super is getting at. 'BUILDING' a new motor from boxes of parts takes a 'builder' . You may get parts that are called' ready to bolt on' but never trust it till you yourself have disassembled, inspected, measured, and checked that it fit's 'RIGHT' . Theoretically, the Slummit stroker blocks are ready to start dropping rotating 'assemblies' in and make a motor. But in the end,, it's YOUR responsibility to see that it all goes together right. Especially with a stroker, nothing will EVER be a bolt together. Heck even changing the cam timing will change rod to cam clearance. If you use a cap-screw rod vs a standard GM I-beam rod you will have VERY difference clearance to the bottom of the bores, pan rail and block face. No way can they make a 'one block fit's all' offering. Too many variables. The tolerances such as the thrust surface, journal size, all SHOULD' be on spec and a bolt together. But especially wit the Eagle junk that is finish machined in China,, you better check even that. I have Eagle 4" stroke crank that was + .0007 on the rods, and - on the mains. RIGHT OUT OF THE BOX. You can never just 'trust' anything any more. And ultimately,, who is going to loose here if you don't? They may replace a bad crank, but they aren't going to replace the other parts that get destroyed when it all goes south. __________________ Still playin with trucks, even at my age! When you're dead, it's only a problem for the people around you, because you don't know you're dead. .....It's kinda the same when your STUPID. I just did my taxes and reviewed my SS statement. Thanks to the current administration it looks like I will only have to work till noon on the day of my funeral.