Ivelostcontact

iTrader: (1)

i'm about to take my 882 350 heads back off my l69 and put my 416s back on. i'm running the s/c at 9psi right now, i'll cut it back to 4-5 maybe 6. the cams i was looking at were as follows.

isky racing
2000-6000rpms
int 214 exh 221
advertised int 264 exh 270
lift int .450 exh .465
lsa 112

howards cams
1500-5500
int 215 exh 225
advertised int 268 exh 270
lift int .450 exg .465
lsa 112

am i in the ballpark, any suggestions?

also, cr is 9.5, what head gasket should i use to lower it to 9 if possible.

Doom86

Both of those cams are pretty much the same grind.

I tried them both in DD and the results were basically identical. Tried a few other turbo and blower grinds and found one that DD thinks is much better, just keep in mind DD isn't perfect though it looks good. There was better results had using the more aggressive lobes in the comp NX line but I figured you were trying to keep the lift down to stock tolerances.

this is the cam NX262 12-556-4; http://www.compperformancegroupstore...ry_Code=HFTNHP

Ivelostcontact

iTrader: (1)

Well i'm already going to replace the valve seals in the heads, before i took them off the first time they were leaking. so i plan to replace them before they go back on. if i can achieve that .480 lift by just changing out the springs i'd be good to go. otherwise i'd just go with the howards, i like the idea of 1500-5500 rpm range for dd better than 2000-6000

Ivelostcontact

iTrader: (1)

i'd like to think this setup will make more than my 350 882s and stock cam. that setup at 9lbs ran my buddies ls1 vette and only lost by a car shifting at 5k. trying to get the edge on him. =)

Street Lethal

iTrader: (16)

On a 9:5.1 engine w/0.021 compressed thickness, you will need....;

0.039 (compressed) gasket = 9.175 to 1

or...

0.051 (compressed) gasket = 8.96 to 1

Ivelostcontact

iTrader: (1)

ok, .51 sounds great. i know 305 bore is like 3.7 or something. does the gasket bore matter that much? i don't think they make a .51 in 3.7

Street Lethal

iTrader: (16)

Cometics will make you whatever you need, and yes, the gasket bore matters. For your application they will recommend that you go with either a 3.80" or 3.85" gasket bore, just tell them you need 0.051 compressed thickness, and that you need steam holes. The gaskets will outlast your engine, and expect to pay around $180.00 shipped for them. They are worth every penny, ask me how I know....

http://cometic.com/custom.aspx

Ivelostcontact

iTrader: (1)

alright, awesome info guys, thank you. last thing i need is, spring info for my heads. any recommendations on them. do they have to be a certain strenght, is .480 lift even achieveable with stock heads and new springs, etc etc etc. i currently have the stock 416 springs, which i believe can handle the 4.65 lift cam, but if it doesn't cost an arm and a leg for the springs it probably wouldn't be a bad idea.

Confuzed1

iTrader: (4)

I would take the advice of the cam manufacturer before anyone else on the board for the springs to use.....cam companies normally have recommended springs types and pressures for each cam they sell.

Ivelostcontact

iTrader: (1)

I found some copper head gaskets in 3.85 bore, at .93, .82, .7x, .6x, and .42 ...... can i use say the .93 to drop my cr to 8.5ish or is it way to thick and going to cause issues somewhere say like the rod lenghts or springs?

Doom86

Why do you like the idea of being slower? I don't understand (not trying to be a ***** either). The comp NX cam combo would stomp the other in a drag race or road race and suffer no less driving around town. Look at it like this the NX cam makes +50ft/lbs torque (@2000RPM) and +100hp overall over a stock 350TPI.. Do you hear any of them guys complaining about no low end?

Personally I would go higher then both of them, even more so since you have a T-5.

Doom86

Do not re-use stock springs for anything but stock cam.

I agree to use what ever spring the manufacture calls for. Or at least match the specs to that spring.

Stock springs are usually well worn. The 416 heads I just built the stock springs were so spent I could compress them a bit with my fingers and they were permanently smashed down a good .25 inches.

Ivelostcontact

iTrader: (1)

i see. nx262 it is. i was just worried about to much cam for a dd. i'd truthfull like to see 350+hp to the rear wheels. I know it can be done with the 144, just need the right stuff i guess.

Ivelostcontact

iTrader: (1)

and i was just worried about changing out the springs. shouldn't be hard tho since the heads are already off the car. just watched a youtube video on. didn't seem difficult.

Orr89RocZ

iTrader: (20)

Get a valvespring micrometer and check the install height on your heads now. Its easy to replace springs with the heads off the car. Just need to know what is the installed height so you can select a spring that will give you the pressures and lift capacity for the cam.

A lightweight checker spring with a dial indicator can also be used to check absolute maximum valve lift on the head. This should be where the valve retainer bottoms out on the valve guide boss. Stock heads seem to be in the .470 range but there are guys running .500 or so on stock heads without problems. I'd measure before coming to a conclusion about max height for stock heads.

Doom86

No not hard to change them its just time consuming to do it right. Much easier on a bench then on a car.

You need is a spring compressor (you can rent or buy), a hammer, and a good magnet helps.

You will need a valve spring mic and shims to set the install height on the springs. Also consider a machine shop will assemble them for the cost of the mic in most cases, it doesn't take them more then an hour to do it.

The stock springs will be set at 1.7-1.73 and the comp springs want 1.7. Swapping to aftermarket retainers will probably make it a bit more, which is good since you are close to "max" lift for seal/retainer clearance.

Ivelostcontact

iTrader: (1)

cool, i just so happen to have a friend whos dad owns a machine shop. i might just go that route then, get the heads polished up while i'm at it. interesting stuff here guys. thank you.

Orr89RocZ

iTrader: (20)

Yeah take them off, set them up with screw in studs and grind down the rocker boss. Can open up the spring pockets for larger diameter springs but dont have to since there are tons of good small diameter stuff