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Discussion Starter · #1 · (Edited)
I'm looking for a new cam to optimize my combo. I will be installing a new cam after the race season is over. I'll use what I've got for now.

I'm looking at a Lunati solid pn 402B4LUN
275/281 (@.05), .669/.675, 108 LSA.

The heads I'm running are basically Edelbrock RPM's sold to GM. They flow very well up into the .700 range, and I want to take advantage of that. The best ET so far is in my signature. The only changes planned for this summer is an anti-roll bar from TRZ motorsports. All else is the same.

Here's the current combo:

454 .060 over
GM forged crank, Eagle rods
GMPP alum rectal heads, 2.19/1.88 valves
SRP pistons, 12.4:1 final comp
Lunati solid 259/267, .625/.625, 110 LSA
Crane Gold roller rockers
CSR electric water pump
Vic Jr intake, Holley 950HP carb
Mallory comp 250 pump, comp 500 filter/regulator
MSD 6AL, blaster coil
GZMS vacuum pump
Th400, Cheetah SCS shifter
Hughes 4000 stall converter, manual/reverse valve body
Ford 9" rear, 4.10 gears, spool, MT 28" ET's.
rear disk brakes, BMR sway bar, BMR u/lca's
supercomp headers, ultraflow 12" bullets
10 point cage

Any thoughts here, guys?
 

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Discussion Starter · #2 ·
The Crane I was looking at is a little less in duration, but same essential lift. Its the pn 131541, 268/276, .648/.669, 108...I like the duration a little more, but there is less lift. Also like that 108 LSA a little better.
 

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I would try moving the one you have before spending the $$ on a different stick. I run a comp 262 270 @ .050 .637 .635 lift on 108 CL installed @ 106 IIRC. I think Harold said he designed the 270 280 grind for comp and have seen him reccomend that b4, but it would need more stall than your 4000 IMO.
 

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Personally, I think I would try 1.8 rockers on the intakes, and a 1050 Dominator. It would probably be more expensive than changing the cam, but the one you have is pretty good IMHO. From the picture it looks like your front springs are probably too stiff. The front sits a little high. Softer front springs will lower the nose of the car a little and give you more stored energy and more front end travel, which would hopefully help your 60' times. Just a thought.
 

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I agree the the new cam might be a little high on the duration numbers. What rpm are you shifting that motor at. I think that motor right now could benefit from shifting around 7200. Also if you do have a 4000 converter, it could help to be looser. I used a 29.5 tire with 4.88's and a 5500 converter with the crane cam just one smaller than you looked at. Mine was the 260/268 .628/.648.
 

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IMO, that cam is too big for your combo. The last iteration of my .030 over 454 (460) before selling it had the following:

Canfield heads 369/299 @ .700"
2.25"/1.88" valves
12.48:1 static compression
.712" i/e 254/[email protected] 108lsa solid roller
Dart single plane
1" Wilson tapared spacer
HP-1000 carb
2" primary/3.5" collector Super Comps
Flowmaster merge collectors

This combo ran a best of 10.38 at 3,745lbs in very average air. I sold this engine to a friend of mine who installed it in a '67 Camaro. The same combo has gone [email protected]+ at ~3,400lbs in good air. Just yesterday we tried back to back testing on this engine/car with an 1,130CFM Pro System dominator. The HP-1000 was initially jetted 84 front with 4.5" P/V and 93 rear plugged. First pass off the trailer the run was aborted as the engine was lean popping at the top of 1st/2nd. Jetted the carb up to 86f and 95r and made another pass. Car went [email protected] Satisfied with those changes as a baseline we installed the dominator with as shipped 88 square jetting. The car ran a full .1 slower and was down 1.2 mph in the 1/8 [email protected] We then tried jetting the carb up to the same configuration as the HP. As the dominator didn't have any P/Vs installed we went 95f and 96r. The part throttle drivability around the pits was terrible. The carb cleaned up after the burnout and another pass was made. The second pass with increased jetting was identical to the first one. Apparently the engine didn't need as much fuel with the dominator due to decreased signal from the carb. I would have liked to of tried installing a front P/V and jetting the carb down, but we didn't. I feel the dominator should have ran at least as fast as the HP, but I suppose we will never know. The test conditions weren't optimal as the wind was gusting to 20-25 mph at times.

I think you should look for a cam similar to the one listed above. That cam made peak power right around 6,800, but would easily go to 7,400 on the dyno. The engine package mentioned above made an honest 685hp on the engine dyno. If I were picking a cam for that same engine today it would have 6-8 degrees more duration on intake and exhaust (e.g. maybe 260/266).

HTH....
 

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kjet you able to street drive on 93-94 octain were upgradeing comp, and solid roller, close to yours
Redbowtie,

The engine combination above was ran on VP110 always. IIRC the warm cranking compression was ~240lbs. Too much compression for pump gas. I probably should have built the engine with 13.5-14:1 compression, but I knew the chamber of the heads was efficient and I didn't want to have problems with hammering starters, etc... A little more cam and a vacuum pump (engine was built with low tension ring set) would pick that engine up 30-40BHP easily.
 

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Discussion Starter · #14 ·
i run a lunati 666/623 256/260 @.50 solid roller. its a very good cam. if you factor in the lash its around 630/600 lift. i run 11.51 @117 so far with a tight 300 stall B&M converter and with 8.1 compression. ive ran this cam with close to 12.1 compression and it was a animal. .02
I have a solid, not a solid roller, but thanks for the suggestion.
 
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