Roller cams again.
Thread Starter
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
You guys are wimps on adjusting the rockers! 
I have run a solid cam for years and the adjustment on them is way overstated. I adjust them every spring and maybe find one or two that is a coupe of thou out. I love tinkering with it also. The solid adjustment certainly would not keep me from running solids. Even if it meant every 1000 miles it would be no big deal. As far as the noise from the solids it is music to me. At idle to the untrained ear most think the motor is coming apart. Once you get into the throttle you can't hear anything but motor anyway. A DD I would run hyd. cam but for the weekend fun toy why not solids.
I have run a solid cam for years and the adjustment on them is way overstated. I adjust them every spring and maybe find one or two that is a coupe of thou out. I love tinkering with it also. The solid adjustment certainly would not keep me from running solids. Even if it meant every 1000 miles it would be no big deal. As far as the noise from the solids it is music to me. At idle to the untrained ear most think the motor is coming apart. Once you get into the throttle you can't hear anything but motor anyway. A DD I would run hyd. cam but for the weekend fun toy why not solids.
Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
Lifters are more expensive than the cam. I just happen to have a Comp XR286R, 577 intake lift, .583 exhaust lift. 286/292 advertised duration, 248/254 duration at .050", 110 LSA, small base circle brand new in the box I'd take $200 for.
Melting Slicks
Joined: Jul 2006
Posts: 2,373
Likes: 6
From: Baltimore MD
You guys are wimps on adjusting the rockers!
I have run a solid cam for years and the adjustment on them is way overstated. I adjust them every spring and maybe find one or two that is a coupe of thou out. I love tinkering with it also. The solid adjustment certainly would not keep me from running solids. Even if it meant every 1000 miles it would be no big deal. As far as the noise from the solids it is music to me. At idle to the untrained ear most think the motor is coming apart. Once you get into the throttle you can't hear anything but motor anyway. A DD I would run hyd. cam but for the weekend fun toy why not solids.
I have run a solid cam for years and the adjustment on them is way overstated. I adjust them every spring and maybe find one or two that is a coupe of thou out. I love tinkering with it also. The solid adjustment certainly would not keep me from running solids. Even if it meant every 1000 miles it would be no big deal. As far as the noise from the solids it is music to me. At idle to the untrained ear most think the motor is coming apart. Once you get into the throttle you can't hear anything but motor anyway. A DD I would run hyd. cam but for the weekend fun toy why not solids.
Drifting
Joined: Nov 2002
Posts: 1,951
Likes: 1
From: Shore NJ
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Your not going to lose any power up top unless you cut way back on the duration, automatic wider power band with the roller a 114 LSA will stretch the power band up higher even more.
just my 2 cents worth, with all the gearing you have with the 5 speed manual trans 3.70 rear gearing, I would not even consider going any lower then 245 .050. use a 114 LSA to keep the computer happy running the fuel injection. unless your really unhappy now with your power range with 252 .050 don't go drastic cut all the teeth out of your ride, you have all kinds of gearing for torque.
just my 2 cents worth, with all the gearing you have with the 5 speed manual trans 3.70 rear gearing, I would not even consider going any lower then 245 .050. use a 114 LSA to keep the computer happy running the fuel injection. unless your really unhappy now with your power range with 252 .050 don't go drastic cut all the teeth out of your ride, you have all kinds of gearing for torque.
Last edited by Little Mouse; Jul 10, 2009 at 01:10 AM.
Thread Starter
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Already have a set of roller lifters that I bought a year ago.
No daily driver here at all.
Cam duration is the big question as is lobe seperation angle.
I'm liking Gkulls cam and he has real owrld experience with a few cams and has run them in his "small"383 as he says.
No daily driver here at all.
Cam duration is the big question as is lobe seperation angle.
I'm liking Gkulls cam and he has real owrld experience with a few cams and has run them in his "small"
383 as he says.
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Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Already have a set of roller lifters that I bought a year ago.
No daily driver here at all.
Cam duration is the big question as is lobe seperation angle.
I'm liking Gkulls cam and he has real owrld experience with a few cams and has run them in his "small"383 as he says.
No daily driver here at all.
Cam duration is the big question as is lobe seperation angle.
I'm liking Gkulls cam and he has real owrld experience with a few cams and has run them in his "small"
383 as he says.Last edited by Little Mouse; Jul 10, 2009 at 03:58 AM.
Thread Starter
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I think I have settled on a solid roller. 242/248 @ .050. Lift with a 1.5 is at .570/.576. No need to go higher with these heads, they don't flow any better from .500 to .600. The LSA will be a 112. This will be a custom grind billit cam. I talked to Comp Cams and the yactually wanted to go a little larger on the duration. This one should provide good performance and keep the O2 sensors happy with a lot less overlap.
Melting Slicks
Joined: Jul 2006
Posts: 2,373
Likes: 6
From: Baltimore MD
I think I have settled on a solid roller. 242/248 @ .050. Lift with a 1.5 is at .570/.576. No need to go higher with these heads, they don't flow any better from .500 to .600. The LSA will be a 112. This will be a custom grind billit cam. I talked to Comp Cams and the yactually wanted to go a little larger on the duration. This one should provide good performance and keep the O2 sensors happy with a lot less overlap.
Last edited by Billysvette; Aug 18, 2009 at 09:24 PM.
Race Director
Joined: Apr 2000
Posts: 17,676
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
There is one hydraulic roller that has always mystified me. It is the Comp Cams 280HT.
With only 230deg duration it get .560" lift with 1.6 rockers you are near .600" lift with no reduction in lift because of valve lash a solid roller would have. It is the Magnum 286HR.
It has more lift with the same duration as solid ( street ) rollers. Someone here is running it an loves it
With only 230deg duration it get .560" lift with 1.6 rockers you are near .600" lift with no reduction in lift because of valve lash a solid roller would have. It is the Magnum 286HR.
It has more lift with the same duration as solid ( street ) rollers. Someone here is running it an loves it
Thread Starter
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Thread Starter
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
There is one hydraulic roller that has always mystified me. It is the Comp Cams 280HT.
With only 230deg duration it get .560" lift with 1.6 rockers you are near .600" lift with no reduction in lift because of valve lash a solid roller would have. It is the Magnum 286HR.
It has more lift with the same duration as solid ( street ) rollers. Someone here is running it an loves it
With only 230deg duration it get .560" lift with 1.6 rockers you are near .600" lift with no reduction in lift because of valve lash a solid roller would have. It is the Magnum 286HR.
It has more lift with the same duration as solid ( street ) rollers. Someone here is running it an loves it
Burning Brakes
Joined: Oct 2000
Posts: 779
Likes: 1
From: Minneapolis MN
Ah. Now I see why you were having trouble with FI and a lumpy idle.
Mass Air systems are great in the sense that you can basically drive it with no tuning - the downside is that you can't tune-out issues like a rough idle or lots of overlap up through 2500. On my megasquirt, I can ask for closed loop O2 feedback only in cruise rpm/load areas.
Mass Air systems are great in the sense that you can basically drive it with no tuning - the downside is that you can't tune-out issues like a rough idle or lots of overlap up through 2500. On my megasquirt, I can ask for closed loop O2 feedback only in cruise rpm/load areas.
Race Director
Joined: Apr 2000
Posts: 17,676
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
I was a little afraid to go to short on duration because of detonation. With 242 on a solid it is about 234 on a hyd roller due to valve lash. On the solids you have to take away 1 degree of duration for every .002 of lash or close to it. It is tough to compare hyd and solids of the same duration. Comp Cams actually wanted me to run 248/254 @ .050 duration on a solid roller. I thought this might be a little much and push the power band up with more rpm. This setup should make good power to 7000 rpm if my heads will flow enough. I'll have to put it on the dyno to be sure about it.
Thread Starter
Race Director
Joined: Dec 1999
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From: Forked River NJ
This is why I am going down to the 242/248 with a 112 LSA. The overlap should be in the low 20s instead of the high 30s where I am now. I did not say it was perfect but I don't want ot go to short and detonate or not have any power in the upper rpms.
Team Owner
Joined: Apr 1999
Posts: 21,953
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Just because your heads don't increase in flow doesn't mean that you need to stop the lift. higher lift = more time at max flow. You have to remember that as rpm rise you start talking about 1/1000 of a sec of total valve open time. That is why you see a very fast drop off in power at some higher rpm. Increasing the head flow potential puts the quick drop off at a higher rpm. It is a simple math formula to fill a cylinder. Time of open valve or duration X rpm, head flow in CFM at each valve lift number, how much time the valve spends at each lift height. That is why a steep ramp solid cam can flow so much more when compared to it's small lobed H-flat cam or even a h-roller
Buy at least 1.6 RR's 1.7's would even be better
Buy at least 1.6 RR's 1.7's would even be better
Thread Starter
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
VALVE ADJUSTMENT .016 .016
GROSS VALVE LIFT .571 .577
DURATION @ .015
TAPPET LIFT 280 286
VALVE TIMING OPEN CLOSE
@ .050 INT 13 49
EXH 60 8
SPECS FOR CAM INST. @ 108.0 CENTERLINE
INT EXH
DURATION @ .050 242.00 248.00
LOBE LIFT .381 .385
LOBE SEPARATION 112.0 FIRING ORDER STD
ROCKER ARM RATIO 1.50 1.50 REQ SHIP DATE
This should work out well. 21 degrees total overlap with a 112 LSA should be fine with the computer and O2 sensors.
GROSS VALVE LIFT .571 .577
DURATION @ .015
TAPPET LIFT 280 286
VALVE TIMING OPEN CLOSE
@ .050 INT 13 49
EXH 60 8
SPECS FOR CAM INST. @ 108.0 CENTERLINE
INT EXH
DURATION @ .050 242.00 248.00
LOBE LIFT .381 .385
LOBE SEPARATION 112.0 FIRING ORDER STD
ROCKER ARM RATIO 1.50 1.50 REQ SHIP DATE
This should work out well. 21 degrees total overlap with a 112 LSA should be fine with the computer and O2 sensors.