Julex

Ok I started back up reading what people are doing for cams and what not, but now I have a few questions. I talked a bit with BatesEngineering and found them to be VERY helpful. Now I was talking about cams for my setup and he suggested rather than doing the 272 regrinds he said it would be best to do a new cam grind to keep the original cam circle, rather than regrinding and making a smaller circle. He was also saying that I should try these specs (sorry he was talking so fast I forgot what he said at what duration he was measuring from but they are:
460 lift intake side, 440 lift Exhaust side, and 241 duration intake, 242 duration exhaust.
What is even better about Bates is that he said they have new blanks that retain the stock cam sensor, so you don't have to run short cam blanks. But he said they are pricey, and they are lol, compared to other cams.

Also what is the advantage of us running a solid lifter, I'm going to buy their lifters anyway since one of mine is cracked, but what will be different? Do ours have a spring inside? I know in our OHV engine the lifters compress due to the spring inside (upgraded to a high tension spring.)

Sorry for stupid questions haha.

xx07cobaltss24xx

not stupid its legitment question lol

Witt

If they can provide you with cam blanks that have the cam sensor pressed in at the correct angle and not just a pair of L61 intake blanks go for it.

With a solid lifter you cannot make adjustments once they are machined to correct lash. They probably provide shims if you would need to do it but the LSJ head will not keep the shims in place. If you are running a solid lifter you can install base circle regrinds with very little comprimise, you throw valvetrain geometry off slightly but the biggest concern with base circle regrinds is the ability of the hydraulic lifter to take up the additional lash. With solid lifters they are machined to fit and this isn't a concern.

Area47

the solid comes into play when you start running extreme rpm's 9k+

my suggestion would be do a slightly less aggressive cam profile. you don't want to **** away all your low end

InfinityzeN

What kind of profile would you suggest then Area, if you could get one ground from blank stock?

Area47

id have to play with numbers. in all honesty, the 272 grinds are not that bad for daily driving and fartin around. you can feel them come in, and go out. all depends on the end user on how aggressive he wants to get with the car.

for a daily driven street deal. comps blower grind isn't bad

after some digging i find the numbers

.423 intake and .436 exhaust valve lift, 252 intake and 262 exhaust duration advertized (210 intake and 218 exhaust @ .050" duration)

Julex

I appreciate all your answers alot.

Trust me I love the bottom end of these cars, Really has the "American Feel" to it. Now here is the kicker, your saying I'll lose bottom end, I'm going to hear ALOT of flak for saying this, but I'm going to be running 10.5:1 compression pistons. Which these will introduce alot of heat, but the guy I talked to at bates said the cams will help with this setup, keep Tq about the same on the low end of the RPM range, but really pull high up too. I will not go turbo with my car, I refuse it, since I already have a turbo cav. And going up blowers might be inline much later once I feel like toying with CAD.

I already have the pistons, that's decided, but ever since finding the broken lifter, it led me to realize I need to build the valvetrain. I wasn't planning on running higher up in the RPM range or anything, but I'm afraid that my springs are just not able to keep up anymore.

Also for those to know, bates sells Single grooved valves, unlike our stock ones, and ferreas which are 3 grooved. And for a good price. I'm Very pleased with there prices, infact really shocked at how fairly priced they are, except for the cams which are almost 900$.

Area47

get cheap parts, get cheap results. im running supertech 78lb springs with zero issues. mine has seen over 8k rpms a couple times. just not a lot.

if bates didn't know what they were doing, they wouldn't be part of the gm racing scene. id fulyl express to them every little detail about how you drive, where you want the torque to be at with a certain pulley size. you goal power over all power. where you want peak to be at. there is a lot of what if's that come into play as well.

InfinityzeN

I'm glad to hear you say that. The comp blower grind was what looked most attractive to me. Just had to figure out if you can get reground to them (most likely not) or were I can pick up a set of blanks with the cam sensor.

If their the only company offering cam blanks with the cam sensor, they can charge what they want for it. But then, that puppy most likely isn't that cheap. Wonder if they would sell just a set of blanks or be able to do the comp grind.

Area47

for reference. the 272's have a .425 int. .405 ext lift.



turbo grind.

gm or bates is the only ones who have lsj blanks.

also, im sure bates can grind them with ease.

InfinityzeN

Oh yea, can tell their a turbo grind. Just like the comp is clearly a blower grind. Higher exhaust lift, longer exhaust duration.

Guess I'll have to give Bates a call myself.

Hummm... wonder what the LSA is...

If it is 110 like stockers, we're looking at 37* of overlap

Area47

break out the trusty calculator, some pen and paper and get prepared for some long ass math

stock is 112.5