Biggest mistake ever- lunati cams

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Rat Bastid said:
At this point, it’s changing SLIGHTLY but I have to do some testing to make sure I’m not going down the garden path to the bottomless rabbit hole.

I pick my @.050 duration based on (mostly) stroke length, then bore size and where I want peak torque to occur.

My math says most of the cams most of the cam grinders calls out doesn’t have enough timing. So they do the easy thing, which is throw some exhaust duration at it (although maybe with some testing I my be slightly LESS opposed to it) and blow the LSA out to get some RPM out of the engine.

And they do that KNOWING they are killing the middle of the torque curve (which is really where all the “street” guys want their power and they bellyache about not enough torque and then they buy a cam that kills power in the middle) because they think (maybe they know) the end user isn’t capable or won’t take the time to clean up the idle and tune the carb and distributor to make the right cam work.

Most of the lobes these cam grinders call out don’t use near enough lift.

The LSA is almost universally too wide for the application.

The @.050 timing is usually not enough and the seat to seat timing is way too long.
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K... explains a bit... i am still ok with my choice :) I would have liked a little more lift but i was trying to be realistic about it and not be my 16 year old self wanting a prostock cam when i only spin to 6000 :)
 
Icetech said:
K... explains a bit... i am still ok with my choice :) I would have liked a little more lift but i was trying to be realistic about it and not be my 16 year old self wanting a prostock cam when i only spin to 6000 :)
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Then you should be making peak torque about 4200-4500 RPM unless you have a powerglide.

Of course, you won’t know where your torque peak is unless you get it on a dyno.
 
Rat Bastid said:
Then you should be making peak torque about 4200-4500 RPM unless you have a powerglide.

Of course, you won’t know where your torque peak is unless you get it on a dyno.
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yeah.. i actually went a little higher on @50 than i wanted cause i wanted a 109lsa and didn't wanna pay for a custom grind.. i ended up at 227/235@50 once i get a gear and converter it will be fine.. just wanted to try not get nuts with the cam..

EDIT: 109 LSA not 108.... thought i went 108.. now i'm annoyed :)
 
Rat Bastid said:
At this point, it’s changing SLIGHTLY but I have to do some testing to make sure I’m not going down the garden path to the bottomless rabbit hole.

I pick my @.050 duration based on (mostly) stroke length, then bore size and where I want peak torque to occur.

My math says most of the cams most of the cam grinders calls out doesn’t have enough timing. So they do the easy thing, which is throw some exhaust duration at it (although maybe with some testing I my be slightly LESS opposed to it) and blow the LSA out to get some RPM out of the engine.

And they do that KNOWING they are killing the middle of the torque curve (which is really where all the “street” guys want their power and they bellyache about not enough torque and then they buy a cam that kills power in the middle) because they think (maybe they know) the end user isn’t capable or won’t take the time to clean up the idle and tune the carb and distributor to make the right cam work.

Most of the lobes these cam grinders call out don’t use near enough lift.

The LSA is almost universally too wide for the application.

The @.050 timing is usually not enough and the seat to seat timing is way too long.
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Lazy cams that tend to be easy on parts due to low loading. That of course in reference to the required spring loading. Kind of what casinos do.
What you state is somewhat what David Vizard uses for cam selection, but coming at it from the other direction. Definately too much LSA and not enough lift.
 
Icetech said:
K... explains a bit... i am still ok with my choice :) I would have liked a little more lift but i was trying to be realistic about it and not be my 16 year old self wanting a prostock cam when i only spin to 6000 :)
Click to expand...
The lift is an easy fix later if you cut the valve pockets now for more lift and the required valve clearance at that lift. The aftermarket now can supply higher ratio rockers for almost any pushrod engine. Besides valve pockets the pushrod to head clearance should be checked. The length from the rocker pivot center to the valve center does not change. The distance from the rocker pivot to the pushrod cup center is shortened which tends to bring the pushrod closer to the cylinder head. Normally a bit of grinding can provide the necessary clearance.
With the rockers you have now the pushrod to the cylinder head can be measured. The rocker dimensions can be measured and the dimension change on the pushrod side can be calculated. Any required grinding can be done prior to final head installation while the heads are away from the shortblock and can be cleaned of grinding debris. Later the rockers can be replaced to get that lift you wanted or close to it. Way less of a job than replacing the cam.
On my 289 I want around 0.500" lift. To get that with a cam I have I am going to use 1.7:1 Scorpion roller rockers. For stability I am installing screwin 7/16" rocker studs instead of 3/8" studs. For my mild cam I should not need a girdle.
 
Dale Davies said:
The lift is an easy fix later if you cut the valve pockets now for more lift and the required valve clearance at that lift. The aftermarket now can supply higher ratio rockers for almost any pushrod engine. Besides valve pockets the pushrod to head clearance should be checked. The length from the rocker pivot center to the valve center does not change. The distance from the rocker pivot to the pushrod cup center is shortened which tends to bring the pushrod closer to the cylinder head. Normally a bit of grinding can provide the necessary clearance.
With the rockers you have now the pushrod to the cylinder head can be measured. The rocker dimensions can be measured and the dimension change on the pushrod side can be calculated. Any required grinding can be done prior to final head installation while the heads are away from the shortblock and can be cleaned of grinding debris. Later the rockers can be replaced to get that lift you wanted or close to it. Way less of a job than replacing the cam.
On my 289 I want around 0.500" lift. To get that with a cam I have I am going to use 1.7:1 Scorpion roller rockers. For stability I am installing screwin 7/16" rocker studs instead of 3/8" studs. For my mild cam I should not need a girdle.
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I'm using trickflows and harland sharp rockers.. should be ok.. 1.5s though.. which i'm still ok with.. this is a temp motor when i do the stroker i will swap to a bigger cam anyway :) Just want to get the car moving for now
 
Rat Bastid said:
At this point, it’s changing SLIGHTLY but I have to do some testing to make sure I’m not going down the garden path to the bottomless rabbit hole.
Click to expand...
Absolutely
Rat Bastid said:
I pick my @.050 duration based on (mostly) stroke length, then bore size and where I want peak torque to occur.
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Coupled with overlap?
Rat Bastid said:
My math says most of the cams most of the cam grinders calls out doesn’t have enough timing. So they do the easy thing, which is throw some exhaust duration at it (although maybe with some testing I my be slightly LESS opposed to it) and blow the LSA out to get some RPM out of the engine.
Click to expand...
The old crutch adage of a poor flowing exhaust port. It does have some merit to it. I don’t think it a bad thing all the time. Knowing the intake lobe is mostly, in a sense is dictating the rpm range.
But we know there’s more to that.
Rat Bastid said:
And they do that KNOWING they are killing the middle of the torque curve (which is really where all the “street” guys want their power and they bellyache about not enough torque and then they buy a cam that kills power in the middle) because they think (maybe they know) the end user isn’t capable or won’t take the time to clean up the idle and tune the carb and distributor to make the right cam work.
Click to expand...
Ahhhhh, the 110 and wider C-line thing.
Rat Bastid said:
Most of the lobes these cam grinders call out don’t use near enough lift.

The LSA is almost universally too wide for the application.

The @.050 timing is usually not enough and the seat to seat timing is way too long.
Click to expand...
Truth truth truth.
Singing my song!
Icetech said:
I'm using trickflows and harland sharp rockers.. should be ok.. 1.5s though.. which i'm still ok with.. this is a temp motor when i do the stroker i will swap to a bigger cam anyway :) Just want to get the car moving for now
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Then any cam will do.
 
MerlinsMopar said:
Well 1st off, lunati tech support really sucks. 2hrs 45 minutes and got hung up on.
My issue was my mistake tho. I ordered the voodoo cam/lifter and spring PKG. Cam # 10200703. Spring # 73195k which was fine and dandy for stock x head spring height however, I got the speed master heads bug from someone, dumped another 1k into them and assembled the motor. When I went to check spring psi and installed height, closed height was almost a 1/4" more than stock x heads.
Installed height is 1 .84 on the speed master heads and closed psi is 115lb.
Closest spring I could find was trickflow # 16972-16 which show 1.85 installed height at 109lb which may be able to be shimmed to get close. The main issue with them is the outer diameter of 1.46 and the heads use a 1.437 dia spring. Its turning into a big mistake buying this junk. I am ready to pull this cam and throw it thru a window. Should have stuck with Mopar. If anyone has this setup and any helpful information, I sure would appreciate it. I wanted to take the car to Carlisle in July but at this point, I will never make it.
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Do not call Lunati for support. They were purchased by Edelbrock. Call Edelbrock's support line.

I ordered the 20230713LK - The biggest hyd roller they make (made) - from Pace Performance, because they had the lowest price on the cam and lifter set... Heard nothing for a month and then finally called again yesterday and had Pace call Edelbrock and found out that they discontinued that cam....maybe all of the Mopar cams? Who knows...don't care at this point either. Screw them and Comp (Also under Edelbrock now). I'm getting the Hughes Steamroller.
 
Better yet.. call bullet, call Howards, call anyone else... edelbrock is a company that doesn't stand behind their products.
 
Well between this and the e body site, I got the information I was looking for. I also got some informative videos which pushed me to making a smart decision.
I decided to remove the inner springs for cam break in just to give the cam it's best chance to survive.
Spring psi is set and I am using a product called Z paste for the cam, lifters, pushrod tips, and valve tips along with the drivin br30 break-in oil. I was looking for the easy way out and excuses to leave the inner springs in but that's not following the instructions and was foolish to take reputable machinists recommendations, even if it would possibly get thru the break in.
I appreciate all who chimed in on the issue and will post the outcome once I get thru this. I also got a reply for the pc3048 torque specs from speedmaster and they stated 95ftlb with their studs.
I can finally finish what I started without regret.
 
MerlinsMopar said:
Well between this and the e body site, I got the information I was looking for. I also got some informative videos which pushed me to making a smart decision.
I decided to remove the inner springs for cam break in just to give the cam it's best chance to survive.
Spring psi is set and I am using a product called Z paste for the cam, lifters, pushrod tips, and valve tips along with the drivin br30 break-in oil. I was looking for the easy way out and excuses to leave the inner springs in but that's not following the instructions and was foolish to take reputable machinists recommendations, even if it would possibly get thru the break in.
I appreciate all who chimed in on the issue and will post the outcome once I get thru this. I also got a reply for the pc3048 torque specs from speedmaster and they stated 95ftlb with their studs.
I can finally finish what I started without regret.
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Im not sure what Z paste is but there are some questionable cam lubes out there.

Excellent decision to remove the inners.

Excellent decision to use a dedicated break in oil.

Just make sure you have a known good carb and ignition.

Drop the distributor in and line it up so it has at least 30 degrees of timing on it when it fires. 40 degrees is even better. Retarded timing builds exhaust heat and that will stick exhaust valves.

A small oil or water leak isn’t an issue so keep the engine running unless it’s gushing leak.

I start at 2500 RPM and cycle the engine up to 3k or so for a bit and then down to 2k for a bit. Varying the RPM helps keep the lifters rotating.

Once you get through the 20-25 minute break in cycle, cut the filter open and get a look. Drop your inners in and do another 15-20 break in cycle.

Cut the filter open again and if it’s clean screw a new filter on it, change to your regular oil and go beat the snot out of it.
 
Follow Rats advice. I might add have a helper available to run the throttle so you are free to observe things, adjust timing, retrieve tools or whatever.
 
This goes back to the old "you can pull your hair out" trying to make a decision. Just pick one that matches your combo and go have fun. You will leave power on the table "somewhere" no matter which camshaft you chose. All this for a street engine? Ridiculous.
 
Rat Bastid said:
Im not sure what Z paste is but there are some questionable cam lubes out there.

Excellent decision to remove the inners.

Excellent decision to use a dedicated break in oil.

Just make sure you have a known good carb and ignition.

Drop the distributor in and line it up so it has at least 30 degrees of timing on it when it fires. 40 degrees is even better. Retarded timing builds exhaust heat and that will stick exhaust valves.

A small oil or water leak isn’t an issue so keep the engine running unless it’s gushing leak.

I start at 2500 RPM and cycle the engine up to 3k or so for a bit and then down to 2k for a bit. Varying the RPM helps keep the lifters rotating.

Once you get through the 20-25 minute break in cycle, cut the filter open and get a look. Drop your inners in and do another 15-20 break in cycle.

Cut the filter open again and if it’s clean screw a new filter on it, change to your regular oil and go beat the snot out of it.
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Once the intake opens and the piston comes up, that's when it is tdc correct? How do you figure out the 30° with rotating the distributor? Also will that be clockwise or counterclockwise? I always just lined up the cap with the rotor, fired and set the rpm then grabbed the timing light. If there is a better way, I would want to know. I realize that is crucial. Everything will be primed and visually checked for oil before I start it. I have a Holley 750 black diamond series which was more costly than a brawler and used the brawler on my last motor which had a leaking float right out of the box. It stayed running but eventually started flooding it.
 
RustyRatRod said:
This goes back to the old "you can pull your hair out" trying to make a decision. Just pick one that matches your combo and go have fun. You will leave power on the table "somewhere" no matter which camshaft you chose. All this for a street engine? Ridiculous.
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Agreed. Still a lot of $$$ tho. Better safe and good knowledge helps a lot. I only know enough to be dangerous so every little bit of info helps. Also a #s matching motor so a little more stress for me.
 
MerlinsMopar said:
Once the intake opens and the piston comes up, that's when it is tdc correct? How do you figure out the 30° with rotating the distributor? Also will that be clockwise or counterclockwise? I always just lined up the cap with the rotor, fired and set the rpm then grabbed the timing light. If there is a better way, I would want to know. I realize that is crucial. Everything will be primed and visually checked for oil before I start it. I have a Holley 750 black diamond series which was more costly than a brawler and used the brawler on my last motor which had a leaking float right out of the box. It stayed running but eventually started flooding it.
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Yes put the damper on tdc compression stroke. If you are not sure remove #1 sparkplug and put your finger over the hole while bumping it over. With the cap on the distributor mark the dist housing at #1 and #8. #8 is the next terminal clockwise. The terminals are 45 degrees apart. Half way between the terminals is 22.5 degrees. Line the rotor half way between the terminals at 22.5 degrees. Considering some amount of centrifugal advance will be added when it starts this should get you close enough to get it fired off then you can fine tune with your timing light.
Can't stress enough known good carb.
 
MerlinsMopar said:
Once the intake opens and the piston comes up, that's when it is tdc correct? How do you figure out the 30° with rotating the distributor? Also will that be clockwise or counterclockwise? I always just lined up the cap with the rotor, fired and set the rpm then grabbed the timing light. If there is a better way, I would want to know. I realize that is crucial. Everything will be primed and visually checked for oil before I start it. I have a Holley 750 black diamond series which was more costly than a brawler and used the brawler on my last motor which had a leaking float right out of the box. It stayed running but eventually started flooding it.
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When the intake valve closes and the TDC mark comes around you are then at TDC on that cylinder.

To find where 30 degrees is on any damper (or any other degree that you may want to find) is pretty simple.

Take the OD of the damper and multiply that by Pi. Then divide that number by 360 (number of degrees in a circle) then take that number and multiply it by what ever degree number you are looking for.

So…7.25*3.14159/360*30=1.898

That means from the TDC mark on your damper 30 degrees is 1.898 inches. That would be moving clockwise from your TDC mark.

What I do is take a piece of tape about 4-5 inches long and make a mark on the left side that will line up with TDC. Then I measure to the right 1.898 inches and make another mark.

Take that tape and lay the TDC mark on the tape over the TDC mark on the damper. Then lay the tape out CW and where that 1.898 mark is, make a mark on your damper that you can see with a timing light and you have your 30 degree mark.
 
Rat Bastid said:
When the intake valve closes and the TDC mark comes around you are then at TDC on that cylinder.

To find where 30 degrees is on any damper (or any other degree that you may want to find) is pretty simple.

Take the OD of the damper and multiply that by Pi. Then divide that number by 360 (number of degrees in a circle) then take that number and multiply it by what ever degree number you are looking for.

So…7.25*3.14159/360*30=1.898

That means from the TDC mark on your damper 30 degrees is 1.898 inches. That would be moving clockwise from your TDC mark.

What I do is take a piece of tape about 4-5 inches long and make a mark on the left side that will line up with TDC. Then I measure to the right 1.898 inches and make another mark.

Take that tape and lay the TDC mark on the tape over the TDC mark on the damper. Then lay the tape out CW and where that 1.898 mark is, make a mark on your damper that you can see with a timing light and you have your 30 degree mark.
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My damper has up to 60° marked and also grooved every 1/4 turn. So I just spin the crank till say 30° on the damper and line up the cap/rotor?
 
Wow. I never knew that. That just made my brain smoke! Lol Totally makes sense now. Just never thought of setting it up like that. Then just check with a light to dial it in. Most are saying 35° with that cam but don't really need that much to start with.
Rat Bastid said:
Yup. Hell, you’ve got it made. No measuring or math!!
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35 will be good for break in. You can set to what you want for full load timing at ?? rpm after cam is broke in.
 
Awesome knowledge. Really appreciate learning that. I have a good 10-15 rebuilds under my belt over the years. Just turned 60 yrs young last year and just finding that out makes me more wise.
Thanks again!
 
When the EXHAUST valve is closing and the piston is at TDC....Not the intake. That is TDC

Edited to read when the exhaust valve is closing....
 
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