6.0L flat pistons with LS3 heads?
05-10-2012, 03:00 PM
#1
TECH Apprentice
Thread Starter
iTrader: (2)
Join Date: May 2005
Posts: 353
Likes: 0
Received 0 Likes
on
0 Posts
6.0L flat pistons with LS3 heads? I have a 6.0L iron block that has been bored .30 over. I purchased some sealed power flat top pistons for it but unsure if they will work since they are flat top. I have heard ls3 heads you have to watch for PTV clearance. All the other pistons I have seen have valve reliefs cut in them.
Thoughts?
Here are my thoughts on cams.
Comp cam part number 54-456-11
54-459-11
or 54-469-11 This one is the one comp recommended with the heads.
Thanks
Thoughts?
Here are my thoughts on cams.
Comp cam part number 54-456-11
54-459-11
or 54-469-11 This one is the one comp recommended with the heads.
Thanks
05-10-2012, 03:41 PM
#2
My LS3 specs at 0.135"ptv on intake and 0.185"ptv on exhaust. We found that trying to run a cam with relativly small duration but tight (113) lobe seperation. Wouldn't fit due to valve clearance problems. If your going to run a wide lobe seperation like GM with short duration, you'll be fine, its when you try to modify, that will get you into major problems.
05-10-2012, 03:47 PM
#3
I'm posting from my phone, no editing allowed, I meant the ptv was with piston@TDC, sounds like your cam has a 111 degree seperation angle, depending on lift, I would predict you will have ptv clearance issues with a tight seperation. The GM ASA cam has duration like I wanted to run but, lift is only 0.525" to allow for proper ptv clearance.
Lots of experts here on this forum, I found out the hard way that all you read isn't always the truth. I suspect many of the pushrod and timing chain problems posted here on this forum are due to improper ptv clearances.
Lots of experts here on this forum, I found out the hard way that all you read isn't always the truth. I suspect many of the pushrod and timing chain problems posted here on this forum are due to improper ptv clearances.
05-10-2012, 05:07 PM
#4
Teching In
Join Date: Mar 2012
Posts: 12
Likes: 0
Received 0 Likes
on
0 Posts
I'm posting from my phone, no editing allowed, I meant the ptv was with piston@TDC, sounds like your cam has a 111 degree seperation angle, depending on lift, I would predict you will have ptv clearance issues with a tight seperation. The GM ASA cam has duration like I wanted to run but, lift is only 0.525" to allow for proper ptv clearance.
Lots of experts here on this forum, I found out the hard way that all you read isn't always the truth. I suspect many of the pushrod and timing chain problems posted here on this forum are due to improper ptv clearances.
Lots of experts here on this forum, I found out the hard way that all you read isn't always the truth. I suspect many of the pushrod and timing chain problems posted here on this forum are due to improper ptv clearances.
Not sure what good measuring this way is doing. PTV clearance is not just about the physical clearance, but piston to valve timing. At no time should any valve be at full lift with the piston at TDC. When checking for clearance you are ensuring that the piston and the valves are not out running each other.
In my experiences, you should have adequate PTV clearance with this camshaft.
I'd say from my experience, if you do not mill the heads you should have adequate PTV clearance with the specs for the cam listed.
For instance, the intake begin to open at 26 degrees before TDC on the cam you suggested. Full lift should occur at around 107 degrees BBDC. So in this movement the piston is moving down away from the valve as it opens and you do not want the ramp rate to out run the piston and kiss it.
The exhaust, on the other hand, is opening BBDC and is opening toward the piston as it accelerates up the bore. It will reach full lift, begin closing as the piston reaches TDC, and finally close ATDC. You don't want the piston to get there first.
05-10-2012, 05:34 PM
#6
The first cam you listed (54-456-11) is the Comp 269LR HR12.
It's specs are: 607/.614 219/227 112LSA+5°
That cam is nearly identical in specs to what Bortous is running in his LS3/LS2 engine.
~ (Bortous/Ed Curtis spec - 219/227 .625 .619 112LSA +4°)
He is also running flat top pistons and has reported no problems with PTV and his heads have been milled .030. +/-
Here is a link to the thread: https://ls1tech.com/forums/generatio...earned-23.html
It's specs are: 607/.614 219/227 112LSA+5°
That cam is nearly identical in specs to what Bortous is running in his LS3/LS2 engine.
~ (Bortous/Ed Curtis spec - 219/227 .625 .619 112LSA +4°)
He is also running flat top pistons and has reported no problems with PTV and his heads have been milled .030. +/-
Here is a link to the thread: https://ls1tech.com/forums/generatio...earned-23.html
After months of agony I finally have Ed curtis Camshaft installed and tuned on my setup.
I have an ls2 with cnc L92 heads 11:8 compression, ported fast 102mm manifold and a 2200rpm stall converter, 3:91 diff gears.
I have been through two camshafts with this setup a 224/232 115LSA and a 229/242 114LSA.
Both felt like crap and were sluggish and slow even though they made very good numbers.
420rwhp and 470rwhp. Both of these cams still had the standard 3.46 gears and a 3200rpm/2500rpm stall.
Now with Ed's cam which is a 219/227 .625 .619 112LSA+4, the engine has really come alive.
I cannot believe how much torque the engine has made. It pulls hard down low, is ultra responsive, and quick as hell at any speed. 2nd gear pulls are insane and the top end is just as crazy. Off the line performance smashes my two previous cams.
This camshaft made 400rwhp (lost a little peak hp because of the 3.91 gears) but my god it feels way faster than that. the acceleration rate is just so quick and brutal.
The peak torque it made was as much as my larger camshaft but far better spread out and this is on a much smaller stick!!
My goal with this setup was maximum torque throughout the whole rpm range and Ed surely delivered it if not more.
I'm still shocked at how ballistic this small cam is.
The air velocity feels very intense and the engine is so ferocious.
The torque curve comes on hard at 2000rpm, and holds on till the red line.
Just unbelievable. Feels like a different car.
What I have learnt and also from Ed, is that l92 heads are EXTREMELY fussy with cam selection.
It really takes an engineer to give you the correct part.
I was about to remove these heads and go back to LS2 heads because they did not feel good. If it wasn't for Ed, these heads would have been off by now.
Couldn't be happier.
I have an ls2 with cnc L92 heads 11:8 compression, ported fast 102mm manifold and a 2200rpm stall converter, 3:91 diff gears.
I have been through two camshafts with this setup a 224/232 115LSA and a 229/242 114LSA.
Both felt like crap and were sluggish and slow even though they made very good numbers.
420rwhp and 470rwhp. Both of these cams still had the standard 3.46 gears and a 3200rpm/2500rpm stall.
Now with Ed's cam which is a 219/227 .625 .619 112LSA+4, the engine has really come alive.
I cannot believe how much torque the engine has made. It pulls hard down low, is ultra responsive, and quick as hell at any speed. 2nd gear pulls are insane and the top end is just as crazy. Off the line performance smashes my two previous cams.
This camshaft made 400rwhp (lost a little peak hp because of the 3.91 gears) but my god it feels way faster than that. the acceleration rate is just so quick and brutal.
The peak torque it made was as much as my larger camshaft but far better spread out and this is on a much smaller stick!!
My goal with this setup was maximum torque throughout the whole rpm range and Ed surely delivered it if not more.
I'm still shocked at how ballistic this small cam is.
The air velocity feels very intense and the engine is so ferocious.
The torque curve comes on hard at 2000rpm, and holds on till the red line.
Just unbelievable. Feels like a different car.
What I have learnt and also from Ed, is that l92 heads are EXTREMELY fussy with cam selection.
It really takes an engineer to give you the correct part.
I was about to remove these heads and go back to LS2 heads because they did not feel good. If it wasn't for Ed, these heads would have been off by now.
Couldn't be happier.
My engine is standard. It has not been built.
The whole setup was done for the 229/242 lingenfelter camshaft but I was not told that the low end torque curve would suck big time as my camshaft knowledge was not that good. I wanted maximum numbers but not at the expense of a poor low end as my car is a daily.
The l92 heads were milled.
I think 0.35 thou was taken off. Now that I think about it, compression may have even been set at 12:.1.1
Im still running the standard valves but of course the valve springs etc have been upgraded to suit.
We never ran into any PTV clearance with the lingenfelter camshaft and that had .631 lift so with this smaller stick, also no problem.
I took it for a run tonight to test it further.
From 50mph-90mph, the vehicle is quicker than both of my previous camshafts.
Also from 50mph, the car loses traction. I have the new michelin pilot super sport tyres plus the eaton tru track diff and all stiffened suspension bushings in the rear subframe etc and it still manages to lose traction.
My big cam never used to do that even though it made that much torque with the 3:46 gears.
I'm still in awe at the power acceleration rate, and brutality of this combination :-)
The whole setup was done for the 229/242 lingenfelter camshaft but I was not told that the low end torque curve would suck big time as my camshaft knowledge was not that good. I wanted maximum numbers but not at the expense of a poor low end as my car is a daily.
The l92 heads were milled.
I think 0.35 thou was taken off. Now that I think about it, compression may have even been set at 12:.1.1
Im still running the standard valves but of course the valve springs etc have been upgraded to suit.
We never ran into any PTV clearance with the lingenfelter camshaft and that had .631 lift so with this smaller stick, also no problem.
I took it for a run tonight to test it further.
From 50mph-90mph, the vehicle is quicker than both of my previous camshafts.
Also from 50mph, the car loses traction. I have the new michelin pilot super sport tyres plus the eaton tru track diff and all stiffened suspension bushings in the rear subframe etc and it still manages to lose traction.
My big cam never used to do that even though it made that much torque with the 3:46 gears.
I'm still in awe at the power acceleration rate, and brutality of this combination :-)
05-11-2012, 12:14 AM
#7
Not sure what good measuring this way is doing. PTV clearance is not just about the physical clearance, but piston to valve timing. At no time should any valve be at full lift with the piston at TDC. When checking for clearance you are ensuring that the piston and the valves are not out running each other.
In my experiences, you should have adequate PTV clearance with this camshaft.
I'd say from my experience, if you do not mill the heads you should have adequate PTV clearance with the specs for the cam listed.
For instance, the intake begin to open at 26 degrees before TDC on the cam you suggested. Full lift should occur at around 107 degrees BBDC. So in this movement the piston is moving down away from the valve as it opens and you do not want the ramp rate to out run the piston and kiss it.
The exhaust, on the other hand, is opening BBDC and is opening toward the piston as it accelerates up the bore. It will reach full lift, begin closing as the piston reaches TDC, and finally close ATDC. You don't want the piston to get there first.
The alternative is to go to the "Cam GURU" for their $500+ SUPER SECRET profiles (many of which are straight out of Comps catalog) and run what they deem is right for you. You could also use a GM HOT or ASA cam in your build. I can buy Comp rollers through the shop I work at for under $360, so I'll continue to spec my own cams you do what you want, either figure out what will fit or go the "little bus" route trusting someone to do the work for you.
My Comp profile, fit the LS3 with some advancing of the cam timing but, everything was pretty tight (0.040"PTV intake and 0.070"PTV exhaust) that wasn't what I wanted, I plan on beating the CR*P out of this LS3 doing drag racing and autocrossing. In hindsight, I made the mistake of reading postings on this forum and the GM High Tech Performance LS3 cam article and believing what I read before ordering ,my cam. Now it's Mahle piston time, no big deal. The bad: additional cost involved in the build, the good: new WAY STRONGER pistons/rods (going with Manley rods, they were on special last month), the VERY BEST thing is the rotating assembly will be lighter/stronger than stock for those 6800RPM shift points I plan on using.
The following users liked this post:
70Zman (10-22-2021)
Trending Topics
05-11-2012, 09:00 AM
#10
OK I'll put this in the form so people who rode the "little bus" to school can understand: Comp Cams lists cam lobe lifts at TDC in their catalog on a couple of different lobe centerlines (very NICE of them to do this!) Because a LS3 head (uncut) has around 0.135"PTV clearance on an intake valve in a motor with no valve reliefs in the piston (stock GM), you should subtract the minimal valve clearance you want (I wouldn't try to run under 0.075"PTV on intake, 0.100"PTV on the exhaust because exhaust valve is opening as piston approaches TDC while intake is closing) Using the Comp Cams listed data figures, you can see if a cam lobe will fit your motor. Using the example of my LS3, we take the 0.135"PTV clearance, subtract 0.075" to come up with 0.060" total allowable ROCKER ARM LIFT. NOW and I'M REALLY TRYING TO GIVE EVERYONE GOOD INFORMATION, you need to DIVIDE this clearance figure by your rocker arm ratio to find allowable cam lobe lift (the figure Comp gives you in their data) So in my situation, we have 0.060" DIVIDED by 1.7 EQUALS 0.035" lobe lift @ TDC at the centerline closest to what you want to run.
The alternative is to go to the "Cam GURU" for their $500+ SUPER SECRET profiles (many of which are straight out of Comps catalog) and run what they deem is right for you. You could also use a GM HOT or ASA cam in your build. I can buy Comp rollers through the shop I work at for under $360, so I'll continue to spec my own cams you do what you want, either figure out what will fit or go the "little bus" route trusting someone to do the work for you.
My Comp profile, fit the LS3 with some advancing of the cam timing but, everything was pretty tight (0.040"PTV intake and 0.070"PTV exhaust) that wasn't what I wanted, I plan on beating the CR*P out of this LS3 doing drag racing and autocrossing. In hindsight, I made the mistake of reading postings on this forum and the GM High Tech Performance LS3 cam article and believing what I read before ordering ,my cam. Now it's Mahle piston time, no big deal. The bad: additional cost involved in the build, the good: new WAY STRONGER pistons/rods (going with Manley rods, they were on special last month), the VERY BEST thing is the rotating assembly will be lighter/stronger than stock for those 6800RPM shift points I plan on using.
The alternative is to go to the "Cam GURU" for their $500+ SUPER SECRET profiles (many of which are straight out of Comps catalog) and run what they deem is right for you. You could also use a GM HOT or ASA cam in your build. I can buy Comp rollers through the shop I work at for under $360, so I'll continue to spec my own cams you do what you want, either figure out what will fit or go the "little bus" route trusting someone to do the work for you.
My Comp profile, fit the LS3 with some advancing of the cam timing but, everything was pretty tight (0.040"PTV intake and 0.070"PTV exhaust) that wasn't what I wanted, I plan on beating the CR*P out of this LS3 doing drag racing and autocrossing. In hindsight, I made the mistake of reading postings on this forum and the GM High Tech Performance LS3 cam article and believing what I read before ordering ,my cam. Now it's Mahle piston time, no big deal. The bad: additional cost involved in the build, the good: new WAY STRONGER pistons/rods (going with Manley rods, they were on special last month), the VERY BEST thing is the rotating assembly will be lighter/stronger than stock for those 6800RPM shift points I plan on using.
Your measurements are still on the physical of a cam and the measurements taken from the head. The piece you forgot in your whole "recipe" is head gasket thickness.
You say you can get any of these lobes out of Comps catalogs. Well, I want to see if they sell you LSG lobes and get back with us.
05-11-2012, 11:38 PM
#13
Dude, what the hell are you talking about that Comp lists their lift at TDC. Lift is lift no matter where the pistons is. The engine can be a t BDC and the lift is still the same no matter what. I just looked at a few Comp cams and it just says "lift" it doesn't say "lift @ TDC".
Your measurements are still on the physical of a cam and the measurements taken from the head. The piece you forgot in your whole "recipe" is head gasket thickness.
You say you can get any of these lobes out of Comps catalogs. Well, I want to see if they sell you LSG lobes and get back with us.
Your measurements are still on the physical of a cam and the measurements taken from the head. The piece you forgot in your whole "recipe" is head gasket thickness.
You say you can get any of these lobes out of Comps catalogs. Well, I want to see if they sell you LSG lobes and get back with us.
Link: http://www.compcams.com/Technical/Ca...obeCatalog.pdf
Besides lift there is ACCELERATION of the lifter off of the base circle of the camshaft, most LS series lobes are pretty quick in getting with the program of getting that valve off the seat and into the air. I know its a lot of visualization and difficult stuff to envision but, there is LOTS of stuff going on in the operation of a valve train, I feel I'm wasting my time here trying to clarify what will fit and what wont. When looking at the lift figures going from a 106degree centerline to a 110centerline, you can see that retarding the camshaft gives you more room, if you want lots of room you retard it even further like GM does so they don't have to worry about high cost parts such a pistons with valve reliefs in them and those NASTY valve pockets probably increase Emissions output of the motor so in GM's mind it is best to do away with all of that nonsense and make one part fit everything from a Corvette to a 3/4ton pick-up truck.
While the piston to valve clearance can be roughly calculated using the TDC numbers there is almost always the case that the valves get tighter sometime before reaching TDC, but some data is better than none at all.
Last edited by 427 zeo6; 05-11-2012 at 11:48 PM.
05-12-2012, 06:14 AM
#14
Gm does "waste" money on pistons with valve reliefs. The l92 has valve reliefs.
What you need to do is if your short block is together, bolt the heads on, find out where in the cycle max lift happens, set your degree wheel to that spec, And use the dial indicator method.
Or buy a cam and hope for The best.
What you need to do is if your short block is together, bolt the heads on, find out where in the cycle max lift happens, set your degree wheel to that spec, And use the dial indicator method.
Or buy a cam and hope for The best.
05-13-2012, 05:10 PM
#15
TECH Apprentice
Thread Starter
iTrader: (2)
Join Date: May 2005
Posts: 353
Likes: 0
Received 0 Likes
on
0 Posts
I have the block already bored .30 over and pistons for it. I am not going to bore it any further if I do not have to or order different pistons. I have a brand new set of 821 ls3 heads and need to know if anyone thinks I will have PTV contact or issues with the cam I have which is a comp lsr 54-469-11 cam. Here are the specs.
Cam Style
Hydraulic roller tappet
Basic Operating RPM Range
2,000-7,000
Intake Duration at 050 inch Lift
231
Exhaust Duration at 050 inch Lift
247
Duration at 050 inch Lift
231 int./247 exh.
Advertised Intake Duration
281
Advertised Exhaust Duration
297
Advertised Duration
281 int./297 exh.
Intake Valve Lift with Factory Rocker Arm Ratio
0.617 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio
0.624 in.
Valve Lift with Factory Rocker Arm Ratio
0.617 int./0.624 exh. lift
Lobe Separation (degrees)
113
Camshaft Gear Attachment
3-bolt
Intake Valve Lash
0.000 in.
Exhaust Valve Lash
0.000 in.
Computer-Controlled Compatible
Yes
Grind Number
281LRRHR13
Cam Style
Hydraulic roller tappet
Basic Operating RPM Range
2,000-7,000
Intake Duration at 050 inch Lift
231
Exhaust Duration at 050 inch Lift
247
Duration at 050 inch Lift
231 int./247 exh.
Advertised Intake Duration
281
Advertised Exhaust Duration
297
Advertised Duration
281 int./297 exh.
Intake Valve Lift with Factory Rocker Arm Ratio
0.617 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio
0.624 in.
Valve Lift with Factory Rocker Arm Ratio
0.617 int./0.624 exh. lift
Lobe Separation (degrees)
113
Camshaft Gear Attachment
3-bolt
Intake Valve Lash
0.000 in.
Exhaust Valve Lash
0.000 in.
Computer-Controlled Compatible
Yes
Grind Number
281LRRHR13
05-13-2012, 07:34 PM
#16
Teching In
Join Date: Mar 2012
Posts: 12
Likes: 0
Received 0 Likes
on
0 Posts
OK I'll put this in the form so people who rode the "little bus" to school can understand: Comp Cams lists cam lobe lifts at TDC in their catalog on a couple of different lobe centerlines (very NICE of them to do this!) Because a LS3 head (uncut) has around 0.135"PTV clearance on an intake valve in a motor with no valve reliefs in the piston (stock GM), you should subtract the minimal valve clearance you want (I wouldn't try to run under 0.075"PTV on intake, 0.100"PTV on the exhaust because exhaust valve is opening as piston approaches TDC while intake is closing) Using the Comp Cams listed data figures, you can see if a cam lobe will fit your motor. Using the example of my LS3, we take the 0.135"PTV clearance, subtract 0.075" to come up with 0.060" total allowable ROCKER ARM LIFT. NOW and I'M REALLY TRYING TO GIVE EVERYONE GOOD INFORMATION, you need to DIVIDE this clearance figure by your rocker arm ratio to find allowable cam lobe lift (the figure Comp gives you in their data) So in my situation, we have 0.060" DIVIDED by 1.7 EQUALS 0.035" lobe lift @ TDC at the centerline closest to what you want to run.
The alternative is to go to the "Cam GURU" for their $500+ SUPER SECRET profiles (many of which are straight out of Comps catalog) and run what they deem is right for you. You could also use a GM HOT or ASA cam in your build. I can buy Comp rollers through the shop I work at for under $360, so I'll continue to spec my own cams you do what you want, either figure out what will fit or go the "little bus" route trusting someone to do the work for you.
My Comp profile, fit the LS3 with some advancing of the cam timing but, everything was pretty tight (0.040"PTV intake and 0.070"PTV exhaust) that wasn't what I wanted, I plan on beating the CR*P out of this LS3 doing drag racing and autocrossing. In hindsight, I made the mistake of reading postings on this forum and the GM High Tech Performance LS3 cam article and believing what I read before ordering ,my cam. Now it's Mahle piston time, no big deal. The bad: additional cost involved in the build, the good: new WAY STRONGER pistons/rods (going with Manley rods, they were on special last month), the VERY BEST thing is the rotating assembly will be lighter/stronger than stock for those 6800RPM shift points I plan on using.
The alternative is to go to the "Cam GURU" for their $500+ SUPER SECRET profiles (many of which are straight out of Comps catalog) and run what they deem is right for you. You could also use a GM HOT or ASA cam in your build. I can buy Comp rollers through the shop I work at for under $360, so I'll continue to spec my own cams you do what you want, either figure out what will fit or go the "little bus" route trusting someone to do the work for you.
My Comp profile, fit the LS3 with some advancing of the cam timing but, everything was pretty tight (0.040"PTV intake and 0.070"PTV exhaust) that wasn't what I wanted, I plan on beating the CR*P out of this LS3 doing drag racing and autocrossing. In hindsight, I made the mistake of reading postings on this forum and the GM High Tech Performance LS3 cam article and believing what I read before ordering ,my cam. Now it's Mahle piston time, no big deal. The bad: additional cost involved in the build, the good: new WAY STRONGER pistons/rods (going with Manley rods, they were on special last month), the VERY BEST thing is the rotating assembly will be lighter/stronger than stock for those 6800RPM shift points I plan on using.
Then could you explain how this spec works with piston dwell and valve ramp rates?
This may be a pertinent spec for cam designers, but I have never found a practical use engine building.
05-13-2012, 11:21 PM
#17
TECH Apprentice
Thread Starter
iTrader: (2)
Join Date: May 2005
Posts: 353
Likes: 0
Received 0 Likes
on
0 Posts
54-469-11 because it was the smallest one designed for the rectangular ls3 heads and this is the cam that the guy from Comp recommended for my application over the phone. The guy from Comp said he didnt think I would have any issues with ptv but I would like to double check since some people are on edge saying im chancing the engine. The specs are listed in my previous post.
You said it should have clearance, I just want to make sure you know which cam I plan on going with now.
Thanks
Oh and sorry I still ride the short bus as I figure this out. I figure its better to ask questions and learn than be the fool who turns the key and F*@(S the whole thing up.
05-14-2012, 12:09 AM
#18
In my opinion, asking for opinions on an internet forum where 99% of the people have no first hand experience with your particular setup is asking for trouble.
Also, keep in mind, gm's spec for deck square is .006 from end to end. So you could potentially lose that from one hole to the next.
Also, every engine is different. If your setup is borderline fitting or not without crashing valves, and you don't verify ptv for yourself, that is plain laziness. And you will have nobody to blame but yourself when your buying new valves, gaskets, bolts and whatever else if they do crash.
Asking questions is great, but this is not a question anyone on here can answer 100%. And it only takes 1% to turn you into the fool who turns the key and ***** everything up.
Also, keep in mind, gm's spec for deck square is .006 from end to end. So you could potentially lose that from one hole to the next.
Also, every engine is different. If your setup is borderline fitting or not without crashing valves, and you don't verify ptv for yourself, that is plain laziness. And you will have nobody to blame but yourself when your buying new valves, gaskets, bolts and whatever else if they do crash.
Asking questions is great, but this is not a question anyone on here can answer 100%. And it only takes 1% to turn you into the fool who turns the key and ***** everything up.
05-14-2012, 01:00 AM
#19
Okay I'm going to beat the dead horse some more. Can you show me where in the Comp catalog there is a lobe with .035" lift tdc? According to your figures there is no lobe that will fit a LS3.
Then could you explain how this spec works with piston dwell and valve ramp rates?
This may be a pertinent spec for cam designers, but I have never found a practical use engine building.
Then could you explain how this spec works with piston dwell and valve ramp rates?
This may be a pertinent spec for cam designers, but I have never found a practical use engine building.
05-14-2012, 01:56 AM
#20
427 zeo6. you seem like a knowledgeable guy, but you come off as a total ***. Try not to insult people, you wont earn your respect that way. If you dont care about "respect" why post?
Not everyone knows everything , thats why we post and discuss.
cheers bpatrol
Not everyone knows everything , thats why we post and discuss.
cheers bpatrol