cam talk

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The slips show a huge improvement in the response and reaction of the package. So what changed and what didnt? You lowered the effective gear with the tire swap and lowered the torque peak with the cam swap. I dont think an improvement of .17 in 60' with little improvement in the incrementals says it's the cam choice. So what do I think the package needs? You still have not said what the trap rpm was and is. IMO, the trap rpm will tell me what carb might be best. Under 6500, the 750 will prob be best. Over 6500 a 4150 series 850 would probably do better properly tuned. The convertor IMO is all off. Which is another reason I think the car is sluggish and lazy. And knowinf the trap rpm vs mph you can calculate slippage. Not as good as trap rpm in the 1/4, but doable. I think an 8" with a slightly lower stall speed might be better. Another trick you can try would be to tighten the lash on the exh side by .005" and see if the car picks up.
 
for trap rpm when the 306 mag was init i would shift at 6800/7000 and just as i shift i would be crossing the 1/8 light so i cant really say what it would be with that cam....now with the 282 it 5000...as for the verta yea i already talked to lenny about a new 1 so thats in the plan for this year, but i think its going to be a 904 instead of the 727....and thanks for the tip i'll try that on my next outting......my buddy has a 8'' 5000 that was behind his 340 we are going to try it with the 727.......i also plan to try a smaller carb and see if it picks up any....i was looking over my papers and the 9.5 verta was set for 5500 maxed out what frank told me on the phone last time i called ( a few weeks ago) and he told me to go 8'' as well.. as for slip if i did it right i came up with 24% which is way much i know should be about what 5 or lessthanks and keep the good info comeing sorry (what changed and what didnt) stayed with the x-cal intake,changed carb from custom 850 to 950hp,same trans and verta changed gears from 5.13 to 4.57 and changed tire from 10/29w m/t slick to 27/10.5 qtp thats it...i went the 1/4 mile in the street and only turned 7200 crossing the traps with 306 mag and 5.13 with 29w
 
Too many changes at once... slippage has to be calculated in 3rd gear, and your rpm has to be higher than the flash stall of the convertor... So you may not be able to get it until you hit a longer track. That custom 850 was probably flowing more, right? I dont think you need more than a dry flowed 850 for it. You'll probably find a good 750 will be quicker in the 1/8 for you.
 
yea that 850 flow pretty good...as far as the changes go it never made any diff. in the motor or the time slips....at the track 1 night we went from like 32 degrees to 38 car never changed went right back out and ran same #'s put ss springs on nothing changed until i figured out the chain problem....now if i move the dist. evrything else moves up or down...what do you think the 306 mag would work best with as far as comp. and head flow.....
 
No. I think it likes the split pattern with what you have now. That was why i said give it less lash on the exh (fool it into thinking theres more exh lift and duration) and see what that does. It might want even more and you can run a 1.6 rocker on the exh side too. Or re-cam it. To use a single pattern you need a good relationship between intake and exh port floe, and set of properly sized headers, which in your case I'd bet are a step starting at 1 5/8 and going up to 1 7/8 (2 steps) with tunable collectors. When those parts are working well with each other you can get the single pattern and it will love it.
 
thanks for the info im not taking this little motor apart .thanks for going along for the ride on this post......i plan to try some of the sugg. stuff to try and inprove on the time slips......
 
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