Chevrolet LS series mechanical roller valve train
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Chevrolet LS series mechanical roller valve train
Help me begin my education of the LS engines mechanical roller valve train.
Questions:
*considering the LS3/L92 rectangular-port head.What is required for valve springs and rockers to accommodate adjustable rockers and .750" range lift?
*This engine will spin in the 7800 RPM range and make around 700 horse. It will be carburated with a powerglide, dedicated, trailered, serious drag race package.
I am not interested in a non-adjustable, hydraulic valve train.
Questions:
*considering the LS3/L92 rectangular-port head.What is required for valve springs and rockers to accommodate adjustable rockers and .750" range lift?
*This engine will spin in the 7800 RPM range and make around 700 horse. It will be carburated with a powerglide, dedicated, trailered, serious drag race package.
I am not interested in a non-adjustable, hydraulic valve train.
Larry Woodfin - Team Woodfin Racing - Owner, Woodfin Automotive
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Re: Chevrolet LS series mechanical roller valve train
Thank You about the Manley spring.
For future reference, the LS series has many options and all the parts and modifications we are accustomed to with the generation 1 SBC are also available for the LS series. Mechanical, link bar roller lifters, adjustable & shaft rockers, valve springs to accommodate.750" lift. Also, Brodix, Dart, and GM offer a number of race head packages.
For future reference, the LS series has many options and all the parts and modifications we are accustomed to with the generation 1 SBC are also available for the LS series. Mechanical, link bar roller lifters, adjustable & shaft rockers, valve springs to accommodate.750" lift. Also, Brodix, Dart, and GM offer a number of race head packages.
Larry Woodfin - Team Woodfin Racing - Owner, Woodfin Automotive
Re: Chevrolet LS series mechanical roller valve train
Pac 1335 spring. TD rockers. Machine rocker mounting pedestals around .100 to restore geometry.
Re: Chevrolet LS series mechanical roller valve train
I tested last weekend, made 7 passes between 9.001 and 9.102; 149.80 and 150.78, testing various theories. 2600lb Camaro, powerglide, cast single plane and 4500 Dominator. 7800 shift, 7500 lights. 416ci LS3. But with a hydraulic roller. How fast are you wanting to go? Going solid roller this summer, also interested in responses.
Re: Chevrolet LS series mechanical roller valve train
Id be interested to know some details on your 416.D.B.O. wrote: ↑Sat Feb 24, 2018 7:50 pm I tested last weekend, made 7 passes between 9.001 and 9.102; 149.80 and 150.78, testing various theories. 2600lb Camaro, powerglide, cast single plane and 4500 Dominator. 7800 shift, 7500 lights. 416ci LS3. But with a hydraulic roller. How fast are you wanting to go? Going solid roller this summer, also interested in responses.
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Re: Chevrolet LS series mechanical roller valve train
D B O,
the performance you posted is excellent and in the range of what I expect. My build will be about 2900 with driver so a 5.85 1/8 is a good expectation.
Tell us about your LS 3 heads.
the performance you posted is excellent and in the range of what I expect. My build will be about 2900 with driver so a 5.85 1/8 is a good expectation.
Tell us about your LS 3 heads.
Larry Woodfin - Team Woodfin Racing - Owner, Woodfin Automotive
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Re: Chevrolet LS series mechanical roller valve train
I am considering a 4.065 bore x 4.00 stroke, is that what you have?
Larry Woodfin - Team Woodfin Racing - Owner, Woodfin Automotive
Re: Chevrolet LS series mechanical roller valve train
Yes, 4.070 x 4.00. K1/Wiseco rotating assembly. +5 dome, 14.13cr, OEM 5364 Ls3 castings, REV 2.165 intakes, Ferrea 1.60 exhausts. Gavin @ SPS Cyl. Heads ported them. BTR .685 springs/retainers. 3/8 pushrods, Jesel 1.8, 254-266 .658/.639 111+5.(needs more lift, I know). CID intake, untouched, 1050 dominator converted to 2 circuit.
The 7 passes were with 1.5” spacer to get my scoop to seal to carb plate, though with that large of a plenum, don’t know if it hurt or helped or made zero difference. I do know that Racepak said I only had 4” of vacuum, so I need to look at that. I also know the converter is about 500rpm too tight, again based on Racepak graph.
What else?
The 7 passes were with 1.5” spacer to get my scoop to seal to carb plate, though with that large of a plenum, don’t know if it hurt or helped or made zero difference. I do know that Racepak said I only had 4” of vacuum, so I need to look at that. I also know the converter is about 500rpm too tight, again based on Racepak graph.
What else?
Re: Chevrolet LS series mechanical roller valve train
Very cool. Still using gm lifters? Im building a 4.070x3.622 currently, 10cc dome. 4500 carb. Your 416 is pretty similiar to the direction Im going minus the stroke.D.B.O. wrote: ↑Sat Feb 24, 2018 9:10 pm Yes, 4.070 x 4.00. K1/Wiseco rotating assembly. +5 dome, 14.13cr, OEM 5364 Ls3 castings, REV 2.165 intakes, Ferrea 1.60 exhausts. Gavin @ SPS Cyl. Heads ported them. BTR .685 springs/retainers. 3/8 pushrods, Jesel 1.8, 254-266 .658/.639 111+5.(needs more lift, I know). CID intake, untouched, 1050 dominator converted to 2 circuit.
The 7 passes were with 1.5” spacer to get my scoop to seal to carb plate, though with that large of a plenum, don’t know if it hurt or helped or made zero difference. I do know that Racepak said I only had 4” of vacuum, so I need to look at that. I also know the converter is about 500rpm too tight, again based on Racepak graph.
What else?
Re: Chevrolet LS series mechanical roller valve train
Actually, just took out the OEM valves and lifter not long ago. Using Johnson 2110r lifters now, though the LS7’s have seen 7800 many times
Re: Chevrolet LS series mechanical roller valve train
Your car runs good.D.B.O. wrote: ↑Sat Feb 24, 2018 7:50 pm I tested last weekend, made 7 passes between 9.001 and 9.102; 149.80 and 150.78, testing various theories. 2600lb Camaro, powerglide, cast single plane and 4500 Dominator. 7800 shift, 7500 lights. 416ci LS3. But with a hydraulic roller. How fast are you wanting to go? Going solid roller this summer, also interested in responses.
What's stall speed ?
Been on a dyno ?
Randy
Re: Chevrolet LS series mechanical roller valve train
Racepak shows rpm drops back to about 6200-ish after a 7800 shift.
No Dyno.
No Dyno.
Re: Chevrolet LS series mechanical roller valve train
Flash at starting line ?
Care to share what the current cam is ? the lobes etc.
Randy
Re: Chevrolet LS series mechanical roller valve train
Launch at 5000, rpm instantly climbs to 6200, then converter lugs to motor down to 6000 and then climbs to shift point.
EPS designed cam with Cam Motion lobes. 254-266 @ .050 .621/.604 w/1.7 rockers, but I have 1.8 shafts. I set up preload 1/4 turn after zero lash, cold. 111LC installed on 106
EPS designed cam with Cam Motion lobes. 254-266 @ .050 .621/.604 w/1.7 rockers, but I have 1.8 shafts. I set up preload 1/4 turn after zero lash, cold. 111LC installed on 106