Solid Roller camshaft selection those of you running a 408 race application - lobe seperation

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rumblefish360 said:
On a 408;

2.02 - 105.02 LSA
2.08 - 105.68 LSA
2.15 - 106.41

For a 434;

2.02 - 103.56
2.08 - 104.26
2.15 - 105.03

A 26 cubic inch difference between the two. Notice how close the numbers are the trend of which they go. About a degree and a half tighter going to a larger engine. So is a 105 to tight? I don’t think adding two more wider is going to kill it.

According to D Vizard which is Chevy math for the 23* angle. Being the MoPar has a 18* angle, you could probably do with 2* less and be fine. 1* won’t show crap.
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Very true with the four inch crank. I've seen that Vizard states in his seminars a positive correction factor of 0.75 for each point of compression over 10.5:1 and 0.5 of positive correction to LSA for each tenth of rocker ratio increase. So with 12.25:1 as stated by the OP, 1.3 degrees more of LSA. Anywhere from 106 to 108 should be in the sweet spot.
 
rslscobra said:
Thank you! Those Duration numbers are the exact ones recommended by Bullet Cams with a 108 center line and 104 LSA. I am still waiting to hear back from Racer Brown. What converter are you running?
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Sorry missed the converter part.....was running a 904 and it was 5400ish....just switched to a glide last year and had a couple different numbers on it....first was 5500ish with a 4.56 and went 6.59 but it wasn't as consistent as I would have liked so got it loosened up but my guy went farther with it than I would have liked....it's now 6100ish and went 6.64 with a 5.00 gear. 14x32 tires.
 
Garrett Ellison said:
Very true with the four inch crank. I've seen that Vizard states in his seminars a positive correction factor of 0.75 for each point of compression over 10.5:1 and 0.5 of positive correction to LSA for each tenth of rocker ratio increase. So with 12.25:1 as stated by the OP, 1.3 degrees more of LSA. Anywhere from 106 to 108 should be in the sweet spot.
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Thanks for that. Good to have it mentioned.
DV is a serious man when it comes to this stuff. It’s still his deep passion. He deals in facts because that’s what engineers do.

Which way do the correction facts work in?
 
Those calculations are added to the finished degrees of LSA factored by the 128 formula. Likewise, if the compression is less than 10.5:1 or the rocker ratio is less than 1.5:1, then they'd be subtracted from the formulations.
 
Newbomb Turk said:
I sent you a PM
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I’m trying to send you a PM and I don’t know if it’s too late at night to text you. The PM is below.

You once asked if I wanted to sell a set of the lightest S/S springs MP made. I found a set of Facebook on the FABO page.

It s member Mike Koriakos. I do not know his screen name here or if he is here.

https://www.facebook.com/mike.koriakos/
 
So, my push rods are the 5/16 with a .116 wall thickness. I can get by with adding a .060 shim to my current valve springs and then may get 3/8" push rods in .145 wall thickness just to be safe.
 
rslscobra said:
So, my push rods are the 5/16 with a .116 wall thickness. I can get by with adding a .060 shim to my current valve springs and then may get 3/8" push rods in .145 wall thickness just to be safe.
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There is upside and zero downside to running the biggest, thickest pushrods you can cram in. If the exhaust ones are even bigger, that is better still.
I had 7/16 on the exhaust and 3/8 on the intake of a W5 deal.
 
DVs corrrection factor, how it works: once the basic # has been calculated, anything that improves efficiency requires the LSA to be widened slightly. Eg. bigger intake valve, higher CR, etc.
 
Recommendations:

Racer Brown - 270/693 274/683 108 LSA 4000-7500
Crower - 258/685 268/702 105 LSA 4000-7500
Bullet - 271/680 276/670 108 LSA 4000-7500

Not recommended but the following are available too:
Comp Cam - 269/654 276/655 106 LSA 4500-7500
Comp Cam - 275/658 284/661 108 LSA 4800-7500
Howards - 273/680 279/640 108 LSA 4200-8000

Current Cam:
Comp Cam Cston - 254/660 268/660 108 LSA Installed 4 degrees advanced.

So darn confusing! Anyone running one of these?
 
It doesn’t really matter if someone is running any of those……… unless their combo is exactly like yours.

I will say this……… there is no “magic cam”……. But some are better than others.
If you’re expecting “big gains”(40-50hp) from a cam swap, I think you’re going to be disappointed.
However, I do feel like the current cam is leaving something on the table.
 
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PRH said:
It doesn’t really matter if someone is running any of those……… unless their combo is exactly like yours.

I will say this……… there is no “magic cam”……. But some are better than others.
If you’re expecting “big gains”(40-50hp) from a cam swap, I think you’re going to be disappointed.
However, I do feel like the current cam is leaving something on the table.
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I agree with your statement and thats why I am looking to change it out. I don’t expect miracles with the swap either. Just want to give it my own little touch….that’s all.
 
PRH said:
Do you have the grind number from the current cam?
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It was a custom grind. Pic attached of the cam card.

IMG_8663.png
 
Of the six choices you listed, the one I like the least is the Crower.
The others all seem in line.
The two Comps will certainly work fine with the TF springs, since those use high rpm semi-endurance lobes.

If the car will be run at the track with the exhaust system in place, I’d lean towards a 108lsa vs tighter.
 
i think your current cam is to big already. the cams that you posted are very close to the cam in my 414 W8 and there is no way a Trick Flow head will compare to a W8.

B3422W5 has a 565 lift cam and runs 10.20's if i remember correctly and close to your race weight.

sometimes less is more.
 
rslscobra said:
Recommendations:

Racer Brown - 270/693 274/683 108 LSA 4000-7500
Crower - 258/685 268/702 105 LSA 4000-7500
Bullet - 271/680 276/670 108 LSA 4000-7500

Not recommended but the following are available too:
Comp Cam - 269/654 276/655 106 LSA 4500-7500
Comp Cam - 275/658 284/661 108 LSA 4800-7500
Howards - 273/680 279/640 108 LSA 4200-8000

Current Cam:
Comp Cam Cston - 254/660 268/660 108 LSA Installed 4 degrees advanced.

So darn confusing! Anyone running one of these?
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FWIW-the Bullet or smaller Comp get my vote. Overlap is 57.5 and 60.5 (respectively) compared to your current cam at 45.

The Crower doesn’t look much different than your current one at first glance, but does increase overlap to 53 with more lift (dunno about valve springs with added lift and lobe aggressiveness, and PTV clearance becomes a thing at some point).

I think you already touched on it, but a converter adjustment will be of benefit for the new cam.
 
dusterbing the peace said:
FWIW-the Bullet or smaller Comp get my vote. Overlap is 57.5 and 60.5 (respectively) compared to your current cam at 45.

The Crower doesn’t look much different than your current one at first glance, but does increase overlap to 53 with more lift (dunno about valve springs with added lift and lobe aggressiveness, and PTV clearance becomes a thing at some point).

I think you already touched on it, but a converter adjustment will be of benefit for the new cam.
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Yes, I will be getting a different converter as the previous owner tried one and it help with the current cam and setup. So, definitely needed. Also, seat pressure does need to increase with a new cam Trickflow heads are at 240lbs. Will be adding .060 shims to get the seat pressure up to 270lbs. Will also be upgrading the pushrods to 3/8 just because. Ty
 
rslscobra said:
Yes, I will be getting a different converter as the previous owner tried one and it help with the current cam and setup. So, definitely needed. Also, seat pressure does need to increase with a new cam Trickflow heads are at 240lbs. Will be adding .060 shims to get the seat pressure up to 270lbs. Will also be upgrading the pushrods to 3/8 just because. Ty
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You probably have already, but if not it’d be good to make sure you have room to take 060 away, and also add whatever lift increase you’re considering.

Not sure how far you are from bind currently, but shimming with the Bullet grind will put you about 080 closer to it…I wouldn’t have been running springs that have that much wiggle room considering you’d like to be around 050-060 from bind at max lift.

Do you have a spring height mic to verify? They’re not too spendy and would give you some peace of mind.
 
dusterbing the peace said:
You probably have already, but if not it’d be good to make sure you have room to take 060 away, and also add whatever lift increase you’re considering.

Not sure how far you are from bind currently, but shimming with the Bullet grind will put you about 080 closer to it…I wouldn’t have been running springs that have that much wiggle room considering you’d like to be around 050-060 from bind at max lift.

Do you have a spring height mic to verify? They’re not too spendy and would give you some peace of mind.
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Current install height is 2” coil bind is 1.1.
 
9secRR said:
i think your current cam is to big already. the cams that you posted are very close to the cam in my 414 W8 and there is no way a Trick Flow head will compare to a W8.

B3422W5 has a 565 lift cam and runs 10.20's if i remember correctly and close to your race weight.

sometimes less is more.
Click to expand...

I think his current cam has a good bit too much lift, but could use more duration. I suspect those heads aren’t doing anything above 600 lift. Aren’t they as delivered from TF?
Also wonder about the 14 degree split.
 
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B3422w5 said:
I think his current cam has a good bit too much lift, but could use more duration. I suspect those heads aren’t doing anything above 600 lift. Aren’t they as deliver from TF?
Also wonder about the 14 degree split.
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No they have 2.08 Int valves and fully cnc ported. Flow numbers posted if you read back in this thread.
 
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