fgj777

Okay, so I have a 1985 trans am with a 350 in it. I started working on the motor recently and I was wondering what you guy think of my parts list so far.(I have the majority of these parts already)
Parts: Summit racing vortec heads (67cc up to .520 lift), summit racing stage 3 intake (air gap), Msd streetfire distributor, msd spark plug wires, scorpion 1.6 roller rockers, comp cams 282s camshaft kit with new pushrods, double roller timing chain, shorty headers, and a edelbrock 750 carburetor.
What do you think of this setup?

TURBOTOMMY

Looks like fun to me

fgj777

To much for a stock bottom end?

TURBOTOMMY

Na,,,Id Say Your Good togo

fgj777

What kind of numbers do you think I could pull out of this setup?

midias

You most definitely are not good to go, you are going to have issues.
282S cam

http://www.compcams.com/Company/CC/c...?csid=220&sb=2

with .495 lift at intake and exhaust on a 1.5 rocker
That puts you are a .528 lift with a 1.6 that you want to use. That is a recipe for coil bind. Even the .495 is closer than I would feel comfortable with.

You don't state where the 350 came from the compression could be a bit low for that cam.

I would probably go for a smaller carb too but that is a debate I don't feel like getting into.

You don't say what trans, if it is an auto you will need a new stall and lock up kit.

Other than that the magnum cam is a 20+ year old design and mechanical flat tappets can be a PITA. I would look into their extreme energy line. If your 350 is a roller block get a roller cam.

Don't cheap out on headers 1 5/8 minimum primaries.

fgj777

The valve lash is .022 so if I subtract that from .528 I'm down to .506 and if I use 1.5 ratio I'm at .473 because I'm using solid lifters
As for the 750 edelbrock I've already used it before any of my upgrades and it worked fine with no problems.

fgj777

The motor is late 70's but I don't know the exact numbers. Also the transmission is 5 speed manual.

midias

473 puts you right on the edge of safe coil bind margin I would seriously consider trying to get them bare and building them your self or at least installing new springs. The spring rate is also a bit low for 6K RPMs but it will work.

fgj777

So do you think 1.5 scorpions would be a better choice. The only things I haven't bought already is the rockers and distributor.

midias

You should probably ask then buy but that being said IMHO 1.5RR are you only choice without changing the heads for more lift.

IIRC the 282S is .022 at cold probably around .015 or so hot with 1.6RRs you are going to be in seriously dangerous territory.

I like to keep at least .050-0.060 spring bind margin. Although too much and you can run into other issues.

Also IIRC those summit heads are center bolt valve covers so you may need scorpion slim RRs to clear the bolts.

fgj777

I was planning on buying self aligning narrow body scorpions so would .473 be safer? I'm buying arp rocker studs because I don't like the summit ones also

TURBOTOMMY

Changing heads for more lift?? Solid lifter cam,,i missed that sorry,,but my brother's running the summit vortec heads with a Lunati 508 lift hydraulic flat tappet cam with a 250 shot on top of it,,,no problems so far...That cam looks kinda small to me but to each there own..I know alotta guys running a hellu lot more lift on stock vortec heads with a spring upgrade....

midias

Yes you have to make a change to the head to get more lift. It might be new springs or maybe some machining work. I cant remember off the top of my head what springs these heads can accommodate.

fgj777

Did your brother change springs on his vortecs or was he running the stock summit ones that came on them?

midias

Just remember

[valve-spring installed height on the seat – (cam lobe lift × rocker arm ratio) + valve lash – safety margin] gives you the remaining open spring length, which should be equal to or greater than the spring manufacturer’s published coil bind height.

Do some calculations ahead of time. Then you can decide what you think is safe or how willing you are to take a chance on coil bind.

TURBOTOMMY

Stock springs that came on the heads...

fgj777

I think I'll stick to the 1.5 roller rockers to be a little safer lol I'm not trying to break my motor yet. What kind of hp range do you think I could pull out of that set up? I was contemplating just building a 383 out of a summit block and scat rotating assembly if my 350 isn't up for the job

TURBOTOMMY

I remember talking to Summit about those heads,,because my brother ordered them without me knowing..Those heads are way too small for what he was wanting todo,,but he was lured in by the price..If I remember correctly they told me to stay under .525 lift and id be fine..So far so good,,it makes enough power to shatter the hell out of 2 7.5inch rear ends in an S10,,were building an 8.5inch its gotta last longer.....

fgj777

When I was up at summit the guy told me to use 1.6 rockers on that camshaft with my heads saying they weren't to much for the heads I was a bit skeptical about it though