I am building a 350 for my truck.I went through it the other day and found no ridge in the cylinders.Pulled a few main caps and they looked great.So I am assuming the engine is fine.(4 bolt main to)I am planning to have a machine shop put new cam bearings in.And run a comp cams cam kit that is all matched.It has .480 lift for both the intake and exhaust with 230 duration for both.Is this cam to big.The truck will be just a weekend toy.Something to mess around with.Or should I go with a smaller cam.

I have a set of 906 vortec heads.That I am planning to have a local guy port and rebuild them.I plan on running 1.5 roller rockers.The kit I want has springs.I believe they are for regular Small block heads.The guy is supposed to rebuild the heads.With screw in studs,Do alittle porting,New stock size valves,with new seats and springs.He said he should be able to do it all for under 500 bucks.Which is what I was looking for.

I plan on running an airgap intake,650 holley DP,MSd igniton.


So basicly what I am trying to ask is about how much HP and torque am I going to have with a stock bore 350,.480 lift cam,ported vortec heads,airgap intake,650 DP with msd igntion.

I plan on running a 2500-3000 stall convertor with 3.90 rearend gears.

 

That ought to do between 350 and 400 hp. You don't need that much cam lift and duration, it will drink the old gasoline for sure. Something like a Comp XE262 is more than enough and will be more driveable, unless this is just a street toy.

 

Dude thats a very racy cam. it will idle around 1100 RPMS, and will have NO low end torque what-so-ever. I have a 234/244 in my 350 right NOW. it cant even spin the tires...

Now...
<b>I plan on running a 2500-3000 stall convertor with 3.90 rearend gears.</b>

THATS enough to make the thing MOVE. only thing is, how heavy is that truck? A heavy truck will want low end torque no matter HOW much gearing you give it (within reason). 230* @ .050 is ALOT. if your driving it on the street, I would HIGHLY HIGHLY recommend a smaller cam, a smaller stall, and smaller gearing too.

now if you DONT drive on the street much.. then by all means... ]but dont expect fuel economy.

 

I will only be driving on friday and saturday nights and to car shows and stuff like that.I also plan on taking it to the strip.I won't street race it that much.I had a bad experince the other night while racing a new grand am with an idiot driver and don't want to be part of someone getting killed.

to be honest I was just guessing on the cam.I looked through the summit catalog and said ok here is one.There are alot bigger one's and some smaller so it sounds about right.I had planned on a running a tci 10 inch convertor.I might go with something else now.I am still going with 3.90 gears.I want a hard launch.

 

I've had motors with that cam, and I've also had ones with the XE274, also 230° intake duration.... I'll tell you in no uncertain terms, the XE274 had better low-RPM manners, and pulled a good bit harder.

I don't know how much good you can do with Vortecs by porting them; but undercut valves ought to help a good bit. Make sure you get the valve guides cut down so the retainers don't smash into them, and if you want any kind of long-term reliability and high-RPM performance at the same time, get them cut for 1.45" springs and use COmp's part # 986 springs instead of the stock-diameter ones. Above all, don't hallucinate that you're going to run the truck crap that comes on them past about 5000 RPM with any kind of cam like that.

It ought to scream. You'll need some traction improvements for sure.

 

I just ordered the comp cams 270h cam.It's jas 224 duration at .050.With .470 lift.Which is still plenty of cam.I also ordered just the cam and comp cam lifters.I frogot my insurance is coming up here thursday so I couldn't buy everything.

The lifters where 20 more bucks than I though.Old catalog though.

 

I have that cam, check out the sig. it idles at aroudn 800. has crazy power that will scare u, but liek he said i get leik 6-8 miles to the gallon max. hey guys with wut sin my sig if i put a 650 on there with the XE256 would it be a dog? woudl i be liek 300 horse? leik prob mid 14's right? cause man do i need better gas. i am 17 and need a car for everyday and i drive this thing liek once a week. its more of a toy to bring out for me and my freinds when theres no beers lol. thanks

 

I just ordered a comp cams roller timing chain set.And an arp cam bolt kit.

This is the first time I have ordered from summit.And I think it is addictive.I spent 230 dollars today alone.And I still need to order a new oil pump and pan.

 

Yes, you will get better mileage. Probably between 300 and 350 hp. Hot Rod or CHP were making 350 hp with that cam on a 355 ci. I'd guess at least low-14s in the quarter.

 

having the performer RPM couldn;t hurt me right? i was thinkin that a just plain performer would be better matched for them parts but i don;t see how it coudl hurt any right? ok so say i put the XE256 in my car with a edelbrock 650 carb and leave everythign else the way it is. Now what do you think my milage would be? like 15-18 maybe? and liek 10 on it? also does this cam lope at all at idle? or does it soudn basically stock, cause the cam i have now sounds like a race car and i have learned to love it and it is just so awsome sitting at a light and the car is shakin. it just feels badass lol. anyways back on subject, how would all that be? thaks

 

The idle will sound stock but I don't think you'll get 15 to 18 mpg. Maybe 13 or so around town. 20 if you're lucky on the highway.