Need cam guru thoughts/advice

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NC Engine Builder said:
Your results are about what I would expect. The MPH tells the tale. Lost power. But now how much did the cam loose, and how much was the intake. I'm suprised it wasn't worse really, that M1 is a MASSIVE downgrade compared to a pro dominator.
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I think that performance from last Friday night was more to do with the lack of traction and the MP intake, not the cam. As I stated the car spun past the 60 foot light on the first run and past the tree on the second run. I had to satisfy my curiosity about the MP intake and now that I know it'll never be used again!
 
Was the new cam degreed in?

If it turns out you don’t like the new cam, based on you’re description of the damage to the old cam, I’m sure it could be sent back to Bullet and touched up.
 
PRH said:
Was the new cam degreed in?

If it turns out you don’t like the new cam, based on you’re description of the damage to the old cam, I’m sure it could be sent back to Bullet and touched up.
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Yes it was, in accordance with the specs on the cam card.
 

If the Bullet cam uses the particular lobes I think it does……
Assuming I’m correct about that……..
The @.200 numbers for the two cams are-
Bullet 197/202
Comp 193/197

The Bullet has more lift and more high lift area(more area under the curve).

It won’t surprise me if the new cam doesn’t quite run with the old one.
Time will tell.
 
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the comp cam will not keep up with the bullet cam. the M1 won't keep up to the tunnel ram at all. send the bullet cam to get repaired and slide it back in. slap the tunnel ram back on and never look back!!
 
Les Gibson said:
I shift the car at 6500, which I know is a conservative shift point, but I don't like to abuse my equipment unnecessarily. In the 1/4 it does trap around 7000-7200. I have no idea who did the machine work on the W5 heads, and there is minimal epoxy in some of the intake ports.
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8000 isn’t abusing an engine with those parts.
 
Les Gibson said:
I appreciate everyone's responses and opinions on this subject. I should make clear that the only reason that I changed cams is because of the slight damage done to a couple of lobes of the Bullet cam when I had a lifter tie bar break late last season. Both lobes for that cylinder had slight scoring from the lifters rotating in their bore when the tie bar broke. By slight scoring I mean you can see it, but I can just barely feel it with my finger nail. For all I know the Bullet cam may still be perfectly serviceable but I thought it better safe than sorry. In discussing my thoughts on changing cams with the previous owner of the car ( who lives 15 minutes from me) that is when he told me he didn't really like the Bullet cam ( but didn't elaborate on specifics) and thought this Comp Cam would be a good replacement. He told me he felt the Comp Cam would give better top end performance.
Because of the crappy weather we have been experiencing up here in Maine this spring the tracks have been late opening. I was finally able to go to New Oxford Dragway ( 1/8) this past Friday night to do some test & tune runs, but it proved to be fruitless as the track was so green it had no grip. I made two runs. The first run when the brake released the rear tires spun well past the 60 foot light and gave me a 6.26 run at 112. ( normal 1/8 mile passes are in the 5.70s at 118ish.) So I drop air pressure, lowered my launch RPM and loosened the front shocks a couple of clicks and the second run wasn't must better with a 6.23 at 112. I hung it up after that run as it was pointless to do any more passes. I was also trying a Mopar Performance M1 W5 intake that I'd had sitting around as I was curious what it would do. Turns out not much. Engine felt like it was suffocating going down track once I found some traction. So off it came this past Saturday. I thought about putting the Indy single carb intake back on, coupled with Thumper 1050 dominator style carb, but decided to stop experimenting and put the original Holley Pro Dominator dual carb tunnel ram back on as this was on the car when I bought it and I know it works. Planning on running at New England Dragway this weekend as I know the track prep will be top notch and I should get better performance.
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If you broke a link bar it’s a sure sign your spring pressure was down.
 
Newbomb Turk said:
If you broke a link bar it’s a sure sign your spring pressure was down.
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If he’s only spinning the thing 6500, I bet it’s not a spring issue. I mean you have to try pretty hard to loose control of a valve at 6500rpm. Only slightly better than stock springs will go there.
 
Super fast rate solid rollers usually require spring pressure determination by increasing seat and open pressure until parts breakage stops. One of the reasons why there's no such thing as too rigid of a pushrod with that type of camshaft.
 
Newbomb Turk said:
If you broke a link bar it’s a sure sign your spring pressure was down.
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Along these lines, have you put in new springs, or checked spring force of the existing ones? Sounds like they may have been in there a while…they lose performance through use so likely are not what their listed rating is anymore. Your softer cam may crutch this issue a little for the time being.

Would also be good to verify new distance from bind with the decrease in lift. You could shim them some to get back some spring force and get back toward a better distance from bind, thus approaching the max open force available from the spring.
 
dusterbing the peace said:
You could shim them some to get back some spring force and get back toward a better distance from bind, thus approaching the max open force available from the spring.
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Thanks for the reminder on that. The closer the springs operate towards recommended minimum lift, the better control over the harmonics and the less risk of valve float. It’s not just about the pressure, but also about operating the springs near maximum lift to stabilize operation.
 
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Update: After reinstalling the Holley Pro Dominator with dual Venom X carbs reworked by Dominic Thumper my cars performance is right back to where it should be. Finally was able to make some 1/8 and 1/4 runs at New England Dragway this weekend. Best 1/8 run was 5.87 @118 and best 1/4 run was 9.19 @ 145. This is right on par with the cars performance with the Bullet cam installed. So it would appear that I made a decent choice in going with the Comp cam I selected. The earlier fiasco definitely was due to the MP M1 intake.
 
Les Gibson said:
Update: After reinstalling the Holley Pro Dominator with dual Venom X carbs reworked by Dominic Thumper my cars performance is right back to where it should be. Finally was able to make some 1/8 and 1/4 runs at New England Dragway this weekend. Best 1/8 run was 5.87 @118 and best 1/4 run was 9.19 @ 145. This is right on par with the cars performance with the Bullet cam installed. So it would appear that I made a decent choice in going with the Comp cam I selected. The earlier fiasco definitely was due to the MP M1 intake.
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Great to hear, enjoy it!!!
 
Les Gibson said:
I've changed cams in the 422 stroker small block in my Arrow. The cam that was previously in the car was a Bullet grind with the following specs:
Gross lift: Intake .685 Exhaust .682
Duration @ .050 Intake 276 Exhaust 285
LSA 106 Installed 4 degree retard
valve lash hot .026 / .026, set .018 / .020 cold

Current cam is a Comp Cam with the following specs:
Gross valve lift: Intake .659 Exhaust .662
Duration @ .050 Intake 275 Exhaust 284
LSA 108 Installed straight up on the advice of Comp Cams Tech Department.
Valve lash listed on cam card .026 / .028 which I assume is hot, card doesn't specify, set .019 / .021 cold

engine specs are 340 X block 4.10 bore, 4.00 stroke, 13.0 - 1 compression, W5 CNC ported heads, Holley Pro Dominator tunnel ram with dual 850 Venom carbs massaged by Dominic Thumper. Powerglide with 5500 converter, 4.30 rear gear.

The engine builder and previous owner of the car told me he never liked the Bullet cam and has told me this Comp Cam should perform better. My best ET/MPH with the Bullet was 9.12 @ 146 in the 1/4.

My question is what performance can I expect with this cam change. I know there are other variables that will affect performance so I'm asking in general terms what I might expect. I'm worried that I've shot myself in the foot with this change.

Also, with these aluminum W5 heads what would be a good cold lash setting for the Comp Cam?

Should also add that these are both mechanical roller cams with Harlan Sharp 1.5 roller rockers.
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