for a 350....

duration at .050: 224 intake/234 exhaust
lift: .496 intake/.520 exhaust
lobe separation: 112

then with 1.6 roller rockers.....

thanks guys

 

IMHO,
That's too big if you are still running a stock converter, stock transmission governer, stock intake manifold, stock runners, unported plenum, 21 lb. injectors, and 48mm throttle body.

You'll need to address the intake by shortening the runner length, and increasing air flow before that cam is optimal. That's a decent grind for something like a Superram or TPIS Miniram with ported heads.

I'd say the biggest you would want to go with an otherwise stock induction system is 218 degrees on the intake duration with 112 degrees being the narrowest lobe separation angle.

I'd suggest you try a 218/224 Xtreme Energy hydraulic roller on a 112 LSA, then replace the intake manifold with an Accel or Edelbrock piece. the cam is P/N 08-502-8 from Comp Cams.

You'll have to make sure you check your heads to see if the valves can handle the half-inch lift. Not all factory heads can, you know. Some run into clearance problems with the valve steam seal & retainer.

--Daniel Burk

 

#1 you need to work on that TPI system. A Holly Stealth Ram would be ideal for a low budget NEW intake setup. Your heads will need some work to accomodate the cam. I.e. new springs and what not.

#2 a good port job where the ports on the intake side flow around 240 cfm would be sufficient for the time being. A lot of work on the exhaust ports would also be very beneficial.

#3 Gears, convertor, tranny work. 3.42's minimum for the rear. 2400 minimum for the stall, and a nice beefy rebuild on the tranny.

I would bet that setup would net you low 13's easily. My setup in the sig gets me 13.7's and I am on stock heads and TPI.

 

would this be better???

duration at .050: 211 intake/219 exhaust
lift: .530 intake/.560 exhaust
lobe separation: 112


I plan on getting new heads and replacing my stock intake with the LT1 intake anyway, so im just wondering what a good cam size to get would be.

thanks

 

Why are you choosing cams with such high lift numbers? You were advised to lighten up considerably but instead have gone radical.

With that kind of duration but such enormous amounts of lift, you are going to need some serious head work in the springs, guides and retainers area.

What precisely are you trying to build? That kind of cam in a daily driver is not going to make for pleasant commutes.

 

lol, no ****, thats why im asking. i'm trying to get opinions

 

I'll give you a setup from a book that I have. You're gonna be amazed.

492 head castings ( Factory GM heads), 2.02/1.60 valves, 64cc combustion chambers, porting and 3 angle valve job, 10:1 compression, TPIS modified manifold runners and plenum, STOCK Throttle Body, custom PROM (chip), 1 3/4" headers, 228*/236* .490"/.510" lift.


356hp at the crank
420ft. lbs. at the crank

Sounds like my setup with the heads I want and the Intake I want. Other than that I have that setup. I figure that I make 280hp and about 340 TQ or so... maybe more.

Take this motor and use it as a template. I am sure that you would be more than happy even if you made 85% of that kind of power.

 

How droll

Now then, please answer the question before we lose patience with your stupidity.

It is not advisable to act the smartass with those who know more about the subject than you do. If that is your objective then why post here asking for answers??? Perhaps you seek to be banned from the forum???

NO ONE can make any sort of informed choice for you UNLESS you tell us what you plan to do with the car

Is it your daily driver?

Is it just for the strip?

Is it supposed to be something in between?

 

ok sitting........settle down. Just asking about those cams, you dont have to get your shorts in a bunch. I'm planning on using my car for a daily driver and for the strip. I want a cam thats not TOO big, but not too weak. I will be gettin AFR heads and an LT1 intake sometime here, so i was just wondering what would be a good cam size for that combo.

thanks

 

The guy you want to talk to is John Millican. He frequents this board and the one at www.thirdgen.org He is the fellow who more or less pioneered the LT1 intake swap and has his own website with lots of "how-tos" here: http://www.lt1intake.com/services.htm

He is using this Crane roller cam on his engine but remember that this is for a 383 and you have a 350.

Part Number: 113802
Grind Number: H-278-2
Engine Ident: 1957-1987 CHEVROLET V-8 262 THRU 400 CU.IN.
GOOD IDLE, DAILY PERFORMANCE USAGE, MILD
BRACKET RACING, 3200-3800 CRUISE RPM

Lift intake: .467 Lift exhaust: .494

Duration: .222 and .234

Thus you may want to cut back in all areas to compensate for the fact it is your daily driver and a smaller engine.

Look for a cam with duration in the .21x and .22x range, and lift in the .45x to .46x range on the intake and .48x on the exhaust.

Also, if you can get the cam with a 112 or 114 LSA, that will make it much easier for a fuel injection computer to deal with.

The one Daniel Haslett suggested sounds about right for your needs.

 

If you're moving to the LT-1 intake then you shoud choose a cam that better suits it. Assuming you are moving to it relatively soon.

You can dial in more duration with the LT-1 than you can with the TPI setup. THe LT-1 like tighter lobe seps (similar to an old carbureted engine) while the TPI certainly likes a wider LSA.

The first cam you mentioned would probably work very well with an LT-1 intake and aftermarket heads (would need to know ALL the specs to say for sure, but it looks reasonable), even if you went with a tighter LSA (110). The ECM can deal with tighter LSAs just fine- it's just if that will make more power or not based on your cam and intake combo.

I wouldn't go with 1.6s on a cam that already has that much lift if you are daily driving it. I'll just say that I've built MANY daily drivers and 1.6s are "hard" on a valvetrain if the cam is already has aggressive lift characteristics. Stuff doesn't last quite as long.

 

Did everyone miss my friggin post where I laid out a complete engine setup finished with final power ratings?

By the way guys, those cams you recommended are not much bigger than an LT1 cam. That cam was in the .450/.460 range. My cam is a bit bigger and I don't find it to be a pain for street driving at all...