91 silverado 355,carb.

Hello.I have a 91 silverado,regular cab, shortwheel base,two wheel
drive. I use truck everyday to go to work, and I pull a small aluminun
boat and use my truck in the woods.Like to hunt. I want to hop-up
my truck alittle,motor needs overhaul and needs a transmission.
I was thinking of this, I have a th350 in very good condition in my
shop, and I saw several different combinations. What do ya'll think about
this?
350,bored.030 and decked
dart 165/1.94/1.5 valves,( i saw vortec make good power, but i rather
darts, vortec are too thin for me)
kb120 fkattops (looks like 9.5 compression)
cc roller tip rocks and cc dr timing chain
cc xe262 cam
650 holley carb.
a manifold with rpm range upto 6000
my rear end,i already put a 3.73 positve
i putting heads too

Did I miss anything ?


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Nice little torque motor. Use 1 3/4" long tube equal length headers with "X" pipe just behind the collectors, 2 1/4-2 1/2" pipe to the back with mufflers of your choice. RPM intake. All done by 5K.
RPM HP TQ
2000 154 404
2500 195 409
3000 242 424
3500 290 435
4000 326 427
4500 353 411
5000 364 382
5500 325 310

The usual primary would be 1-5/8". Where does the 1-3/4" pipes overtake the smaller ones?

The slightly larger primaries show more torque and hp throughout the range. If you think about it, we used to use 1 5/8" primaries on 265 and 283 Chevies. These are 355's we're talking about here, so they need a little more pipe.

If you do a little math, you can see it easier.
A 1 5/8 pipe is 2.07 square inches in area.
A 1 3/4 pipe is 2.40 square inches in area.
The 1 3/4 pipe is 16% larger.
A 350 is 23% larger than a 283, so even at 1 3/4, the pipe might be just a tad small in comparison to what we used to run on those little mouse motors.

See how my mind works?

I got your reply,techinspector, Thats some really good power for me.
Thanks for the advice with the headers and pipes, I hadn't thought
about that part yet. You said an rpm manifold, I'm assuming you mean
an Edelbrook RPM manifold.
I'll let ya'll know in the future how it went.(hopefully by 6/30/09)
Thanks from, Blazer53

Yeah, it doesn't necessarily have to be an Edelbrock, but a dual-plane, high-rise such as a Weiand Stealth or Professional Products Typhoon.

Use only 1.5 rockers with that cam. That's the way I dyno'd it for you. In my opinion, using 1.6 rockers with an Extreme Energy cam is asking for trouble.

Set your squish to somewhere between 0.035" and 0.045". Again, in my opinion, this is one of the most important aspects of building a street motor that will run on pump gas without detonation. This motor will be building considerable cylinder pressure and could rattle if the squish isn't right.

The stack of parts you're using adds up to 9.001". The nominal block deck height of a small block Chevy is 9.025". If the block is virgin and has never been decked and you slap it together with a run of the mill 0.040" head gasket, the squish will be 0.064" and you could be in trouble.

You can use a thinner gasket so that you don't have to cut the block decks so much. Victor Reinz makes a #5746 composition gasket that compresses to 0.025". With the piston down in the hole somewhere between 0.010" and 0.020", you'd be at your target squish and all will be right with the world.

Hello techinspector1, I looked at the intake manifolds,I think the
weiand slealth,part # wnd-8170 daul plane seems good. But is the
bolt pattern different on that year (91)? Also i looked at your dyno
shows up to 5500rpms. The manifold including Edel. has rpm range
1500-6700. XE262 shows rpm range 1300-5600. Does that matter?
Or make a big different compared to a manifold that makes power
from idle-6000, or from 1500-5500rpms?
Also I read up on deck height I understand about that part.

Thankyou for you help,from Blazer53

P.S. I was looking at the weiand air striker too which is simular too
the edel.rpm air gap, but I think the bolt patteren on this engine is different,
center bolts look like they come straight up and 8 outsiders are angled.
Part #wnd-8501 from Summit.

The following is just my opinion.

Edelbrock made a marketing blunder when they called the Performer a Performer. They should have called it The Chump and described it thusly: "Lightweight aluminum replacement manifold to take weight off the front of your car and provide carb to hood clearance".

The RPM is mis-named. It should have been called the Performer and described thusly: "Lightweight aluminum manifold that produces maximum horsepower and torque on street motors from idle to 6000 rpm's. Over 6000, use a single plane intake manifold."

Here's a Vortec style manifold. Two bolts in each corner for a total of 8.....
http://images.google.com/imgres?img...3D2% 26hl%3Den

Hello again,techinspector1, I can't use vortec manifold. I did some
checking about this motor. I bought the truck two years ago used so I
called the guy up and found out that this was an exchanged motor and
and the bolt pattern is of a latter model. the 8 outsiders are angled and
the 4 middle are facing more downward.
I don't think Edelbrook makes an rpm manifold like that. If I wrong about
Edelbrook, can you help me with the right part #?, If not I might go with a weiand stealth or an weiand action plus-(which is good to 6000rpm)