NightTrain66

pretty good reading material here for those interested. i do not agree 100% with all of his thinking but for the most part I do agree.

http://www.babcox.com/editorial/ar/eb90252.htm

http://www.popularhotrodding.com/tec...ics/index.html

http://www.stockcarracing.com/techar...ths/index.html

Vizard quote:

"There is much said about LSAs that needs to be thrown out with the garbage. First let me make one major point quite clear. For a given spec of engine there is only one LSA that will give optimum torque and horsepower. It is not, as many cam company techs would have you believe, a variable parameter."

Nothing wrong with the Comp XFI "lobes" it is just the placement of then (LSA/ICL/ECL) that hurts the cams in the catalog.

BTW, the Vizard articla will list LCA as LSA. LSA and LCA are the same thing with a different name. I guess it is an older term since my dad still calls it LCA as well.

I sent the OP a cpl of cams he could get thru Comp that were much better than the shelf stuff. Anyone that sells Comp can get them for him. I do not even sell Comp cams or springs at all. I do use there retainers, locks and locators though.

Lloyd

Orr89rocz

I got a similar grind from Bauer. 230 on the intake, .603 lift on a 109. Not an aggressive ramped lobe but makes 400whp on my 383 but its gonna go up soon as i dial in the new tune for the custom MAF and CAI.

you dont always need a aggressive lobe to make power, its more in the head flow and how/when you open the valves during the piston/crank cycle

pr0zac

i have the 280xfi in an otherwise stock lt4 with shorty headers, a 52mm tb and 4.10's. i have a pcmforless tune. its quite a smooth cam.. its more mellow then i think it should be. i don't know if something is off from my car/tune or if its just the cam. the best i could get out of it at the track on all seasons was a 12.7@111.9 and best 1/8th was IIRC a 8.1@90. i think i might have been revving it out more than i should have though.

NightTrain66

my point was if you want a cam with the same amount of overlap (similar idle, vacuum, etc) you can go down in duration (224/230) an dtighten the LSA to get the overlap where it is equal to the 230/236 113 LSA cam.

You would end up with a smaller cam 'on paper" but one that fills/empties the cylinders better and makes more power EVERYWHERE even though it has less duration.

Lloyd

TenSecondZ

For the amount of effort and expense to change a cam, it makes sense to go with a custom cam. Off the shelf cams are designed to be idiot proof thus compromises are made. IE wide lobe separations due to overcamming etc...

Call up Lloyd or AI and get a cam designed around your goals. It's maybe $100 more than off the shelf...big deal. (not to mention Billet vs cast cam core)

As a side note.. Some have had trouble trying to control those XFI lobes, even when using beehive springs. Spend sometime on CZ28.com
and look for results of that cam, not too many are impressed.

Vette Threat

Looking to get a custom cam to replace my 280XFI...pm sent

Vette Threat

I'd say somethings off. My stock LT1 with 130,000 miles, headers, 4.10, roller rockers, 52mmTB stock tune, K&N air filter, ran 12.86@110MPH on a 1.96 60FT "lift" shifting

tpivette

somethings up with your combo/tune... my LT4 with only a hotcam, port-matched intake, free mods, and tune went 12.2 at 116mph. that was shifting at 6500rpms with a half fried clutch

pr0zac

they were 1.99 60 foots fwiw. couldn't launch more than 2000 rpms.