Hydraulic Rollers - Page 3

jmracing · 02-10-2015, 07:36 PM

JMRACING
Go with Comp Cams # 15850-16the best one for the price

Rob Petrie E395 · 02-10-2015, 09:50 PM

I sent Chris at Comp a email and did not expect to hear back till tomorrow but he was able to get back to me tonight.
For those interested here is what he said about the 2 different lifters.

For a race engine the 15850-16 is best for a race application because it only has .030" of travel and it can take over 500#'s of open spring pressure.
The 875-16 has about .100" of travel and can take 400#'s open pressure.

JRyan · 02-10-2015, 10:32 PM

Jeff,

You can only run your '88 as a 138 HP engine with the .921" lifters. I'm sure there is great deal of latitude taken with the "Aftermarket OEM-type lifters permitted" statement by those who like to stretch the rules, but I was told when building our 138 HP Cutlass Stocker, that I had to use the "big" lifter, so we did.

Fortunately, they're able to be shimmed for limited travel, and unfortunately, they're heavy and require the 138HP roller block.

Jerry

Andy G · 02-15-2015, 03:31 AM

When checking the NHRA engine specs for the 1987, 307/138 olds I see that the diameter for these roller lifters is .698".
Is there an advantage to the smaller diameter lifter? I would think that that the larger diameter would be more stable in the bore at higher RPM. The smaller diameter would be lighter. Is the diameter a factor in choosing the better lifter for stock eliminator?

02-10-2015, 07:36 PM	#21
jmracing Junior Member Join Date: Jan 2005 Location: REPENTIGNY, QC. CANADA J6A8G5 514-642-0603 Posts: 39 Likes: 0 Liked 0 Times in 0 Posts	Re: Hydraulic Rollers JMRACING Go with Comp Cams # 15850-16the best one for the price

02-10-2015, 09:50 PM	#22
Rob Petrie E395 VIP Member Join Date: Dec 2007 Location: Woodlawn IL Posts: 1,093 Likes: 162 Liked 220 Times in 79 Posts	Re: Hydraulic Rollers I sent Chris at Comp a email and did not expect to hear back till tomorrow but he was able to get back to me tonight. For those interested here is what he said about the 2 different lifters. For a race engine the 15850-16 is best for a race application because it only has .030" of travel and it can take over 500#'s of open spring pressure. The 875-16 has about .100" of travel and can take 400#'s open pressure.

02-10-2015, 10:32 PM	#23
JRyan Senior Member Join Date: Apr 2003 Location: Aberdeen SD Posts: 642 Likes: 28 Liked 104 Times in 28 Posts	Re: Hydraulic Rollers Jeff, You can only run your '88 as a 138 HP engine with the .921" lifters. I'm sure there is great deal of latitude taken with the "Aftermarket OEM-type lifters permitted" statement by those who like to stretch the rules, but I was told when building our 138 HP Cutlass Stocker, that I had to use the "big" lifter, so we did. Fortunately, they're able to be shimmed for limited travel, and unfortunately, they're heavy and require the 138HP roller block. Jerry

02-15-2015, 03:31 AM	#24
Andy G Junior Member Join Date: Aug 2007 Posts: 4 Likes: 6 Liked 8 Times in 2 Posts	Re: Hydraulic Rollers When checking the NHRA engine specs for the 1987, 307/138 olds I see that the diameter for these roller lifters is .698". Is there an advantage to the smaller diameter lifter? I would think that that the larger diameter would be more stable in the bore at higher RPM. The smaller diameter would be lighter. Is the diameter a factor in choosing the better lifter for stock eliminator?