doublearrow

Title says it, I bought a 96 vortec with 906 cast vortec heads. The block is at the machine shop. I was not going to use the vortec 906 heads but the owner assured me there would be no problems, in fact he says he prefers them over the other vortec heads.
Now ive never done anything like this, and ive got no clue where to go from here. Its going into a 75 and im hoping for 400 to 450 horsepower with good torque. It is majnly a cruise/date night with the wife car.
I think i can use the edelbrock performer vortec intake and a drop base air cleaner and not have any clearance issues?
Ive got no clue what cam or how to pick which cam and i have no idea which rotating assembly to use. ANY advice would be appreciated on which direction to go with the heads i mentioned. Any general tips regarding engine building would be appreciated as well.


Comp cam recommendation from comp last post

Jig A Low

there are literly hundreds of threads about this so I would recommend spending some time searching them and reading them, we will also need alot of info about the car and what you're looking for out of it---we'll need trans type, rear end gears, tire size, etc, etc---- all this comes into the picture when building a motor. for a cam selection, go to www.compcams.com and start playing with their cam selector. after that, give them a call on their tech line and talk to them (warning---I talked to three different people at comp and got three different recommendations for cams)

when I built my 383, I used a XE256H---I have 2.82:1 gears and an auto so I wanted tons of torque (fun city driving) and didn't worry about H.P.-----your motor is different so that may not work for you, in fact, you likely have a roller cam setup (better). you will also need to figure out which heads, intake, exhaust (headers), lifters, rockers and carb you'll be using before selecting a cam for it.

doublearrow

I've done lots of reading and it leaves me more confused, and in fact I think it causes me to overthink things I don't need to. I see guys say use this cam or that cam, my question is how is this determined I guess? Is there a forumula? Has someone built an engine with these heads and that's how they know it works?
Model 1975

Intake: The edelbrock performer vortec I mentioned, again more confused after researching clearance. Some say their's fits fine some say they had to get an l88 hood, summit says it won't fit under a corvette hood. Why do some fit and some don't with a 350 block and the same year car?

Carb:Not sure, I don't know how to go about picking one, again more hood clearance issues that several people have mentioned.

Gears: Not a clue is there a way to find out? From what research I've done there was 4 options that year. The old man I bought the car from knew less about it than I do, he was convinced it was a camaro.

Transmission: THM400 I will have it gone through and a shift kit added once the engine is complete


Tires: Not sure I will have to look when I get off of work.

Heads: The vortec 906 castings I mentioned in the first post.

Stock brakes

I will fix the ac once the engine is done.

As far as lifters, rockers and what not I don't know how to go about picking which ones? When asked people just say Use this or use those, but why? How did they come up with this?

As for driving like I mentioned it will be a street cruiser date night car. Leave black mark every once in a while, possibly a pass or two down the track. More passes as the years go on and I learn more about this.

Frankenvette

I swapped in the Edelbrock vortec performer intake with my stock 80 hood. So what I did was put a blob of play-doh on air cleaner and gently closed the hood. Reopened to see how much clearance I had using the play-doh as reference. I think I had around an 1 inch or so.

242 Motorsports

How much $$ are you willing to spend on the build?

That will help determine a few of the choices such as roller or flat tappet camshaft, which will in turn impact other choices.

doublearrow

I planned roughly 3500ish with full intentions of using a roller cam. Price isnt set in stone due to im doing it in increments.
So far
Complete vortec engine 150
Machine work 275
Machine heads 200
The engine also came with brand new flat top federal mogul 30 over pistons and rings. I dont have to use these and wont if there is something better. I will sell them if i dont.
Figured 350 for roller cam
Machinist says 800 for eagle rotating assembly but if theres something else i need to use i will.

resdoggie

If your lower end is fine then I'd pass on the rotating assembly and put that money towards a set of aluminium heads and sell your vortecs.

242 Motorsports

Chances are the new pistons will be for the 3.48" 350 CID stroke, making them useless for the 3.75" 383 stroke.

$800.00 sounds a little optimistic for the rotating assembly, I'd count on $1000.00 or so to get a quality, balanced kit.
Consider Skip White for the rotating assembly.
http://www.ebay.com/itm/SBC-CHEVY-SCAT-383-ROTATING-ASSEMBLY-FORGED-030-H-BEAM-RODS-22cc-DISH-1PC-/330929046862?pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr&hash=item4d0ce8854e
I would personally re-use the factory roller lifters, spider, etc., and count on $300.00 for a COMP stick.

The Vortec heads will work with this combo, but if there is $$ in the budget, consider Brodix IK180 or IK 200 heads.

Do you plan to do the assembly yourself or pay ($$) to have it done?

BKbroiler

I have a 383 in my car, with Vortec heads, 082 castings but no different than your 906. I have used the Edelbrock performer intake with a Quadrajet carb. A drop base air cleaner with a 3 inch element will easily fit under your hood. The Qjet allows a 2 inch drop to fit. I have an Eagle CAST crank, stock reconditioned rods, with ARP bolts, and JE forged pistons. This setup has survived hundreds of 1/4 mile runs, on the track, with a best of 12.17 and about 7k miles of street driving over a 7 year period. A roller cam, something like a Comp XE274 will give you all the power you need especially at the bottom and mid range from the way you desribe your expectations. You will need to cut valve stem bosses on the heads for the valve lift.

242 Motorsports

This sounds like a good recipe. 12.17 is impressive.

What cam are you using?
What gears?
What trans?
What weight, w/o driver?

BKbroiler

I changed cams over the winter, but I was using a Comp XE262 flat tappet, 3.73 gears, 3,000 stall, TH350, 3,420 lb.

augiedoggy

why in the world wouldn't he use a roller in an engine already designed and setup for one?

242 Motorsports

1: roller will cost more money and sometimes that extra $150.00 is a deal breaker.
2: mild applications have little to gain, performance wise.
3: the much higher lift created by the typical roller cam will necessitate more expensive mods to the Vortec heads.

63mako

Your rear gear ratio is needed to make any decisions or recommendation's.

doublearrow

From reading i did the l48 came standard with the 3:08. Im going to assume this is the ratio for all purposes until i have a chance to pull the cover off.

242 Motorsports

The smallish 262 COMP mentioned earlier by BK will produce mucho low end torque and work fine with a set of 3.08 gears.
It'll have a smooth idle and pull hard as soon as you hit the pedal.

You can easily find a roller cam that specs out like the XE262.

Taijutsu

I'm running a 218-224 HR w/1.6 RRs 350.
It is a little soft off idle, I have 3:55 gears w/M21 trans.
The engine smooths out @ 2200, the sweet spot seems
to be an almost perfect 2800-3000 rpm. 20mpg.
peak rwtq 315 comes on very hard @ 4100.

I drove the orignal combo for 90K, so I knew what
I wanted to change.
Tall gears require low end to get rolling.
Low gears are required for big top end.
You will have to make some chassis improvements.
The vendors will be happy to assist you.

I want to fill in transfer slot in AG intake.
That should improve off idle and low end.

Be honest w/yourself and ask:
How am I going to spend most of my time
driving my car.
A smooth running tq monster is always
fun for a street only car.

People were not being sarcastic when they told you to
do some searching. Most members are not shy about telling
you what they think. We have a few gurus that have been known
to share their hard earned experience. Try to listen.

The better you can define your needs, the better the outcome.
If you are on a budget, you can always add the better heads
later. You will need a stout bottom end.


jmho

R

242 Motorsports

Are you planning headers and free flowing exhaust or are you subject to inspections that require cats?

doublearrow

I have headers on now with dual magnaflow mufflers that i will reuse. Im not too concerned with gas mileage if that matters. We will mainly be around town (midland texas). You mention the cam above would be good with the 3.08, would i be better off getting a different cam and changing gears? I will do some research on a roller cam to match. Thanks

242 Motorsports

The two biggest issues with a gear change is the cost of the operation (especially if there is nothing mechanically wrong with the existing posi and gears) and the additional RPM at cruise speed.

Even the 3.23 gear in my T/A has the Poncho wound pretty tight at 75MPH.