By running an XE256 cam on a bone stock LM1 350 with an 8.2:1 cr? This engine makes 160 hp stock.

i would say ur gonna notice a BIG differnce......at the flywheel im gonna guess 265 or 275 HP......equivalent to around 50 hp or more.....than what u had....i would be willing to bet that itll make more power than i said..... maybe someone else will chime in and say what there opions are.....

*EDIT*

desktop dyno says witha dual plane intake a 600 cfm carb....stock 1.94 1.50 heads....and small tube headers with mufflers and the cam 4 degrees retarted

261hp at 4500
357ft lbs at 2000(----- thats a good low end GRUNT!! :eek:

i was close.... :D

Holy cow! 100 more HP from just a cam swap?? :eek: Tell me this isn't so...for if it is I'm astonished!!

I didn't think I could get much from a low performance smog era 350, especially with an 8.2:1 c.r.

Now what size "small tube" headers are we referring to? It currently has 1 5/8 primary headers feeding thru a dual 2 1/4 exaust with glasspacks however I'm now thinking about putting on the Flowmaster 2 1/2 dual exaust kit using their Super 40 mufflers. This will be ok right?

BTW why would one want to have their cam 4 degrees retarded? :confused:

You don't need 2.5" exhaust. 2.25" is fine. In fact, I think 1-5/8" headers are on the large size for what you have. Better mufflers are a good idea. I use Dynomax SuperTurbos on my driver and like them a lot.

It's not a good idea to retard a cam. That is installing it at more than the LSA (for example, a 110º LSA cam installed at 114º). Straight up (110º at 110º) to 4º-6º advanced (106 or 104 for a 110º cam) is the way to go. Don't be confused by the timing marks on the timing set. The marks are in addition to any advance built into the cam.

The 256 cam is on the large side for an 8.2 engine. If you can get your CR up there are a lot more cams available. Shim head gaskets are a relatively easy way to increase the CR about 1/2 ratio while, in most cases, improving the quench distance.

Well I was thinking of trying to make this engine perform the best I can without rebuilding the whole engine....I figured a cam and intake swap would be a very good idea to extract a little more HP/TQ from this engine.

So an XE256 cam is too big for my application? Then what would be a good cam?

BTW Flowmaster doesn't make a 2 1/4 exaust kit that I'm aware of.

get a good performer intake and while u have the intake off i would take the heads off and do as pat said and change the headgaskets and get more comp. and then ull be able to go even bigger cam and even have more power.....maybe the 262* with 462"/469" lift if u raise ur comp up to 9 to 1 comp.....

The XE256 would be perfect IMHO for a stock 350
Summits sells a complete 2.25" mandrel bent exhaust system with mufflers for A bodies for $129 graemlins/thumbsup.gif

You won't see big gains. Doesn't do a whole lot of good to put a good air/fuel pumping cam in with out using good heads,intake,exhaust. If you can't get the air in...........you can't get the air out. Don't get me wrong......you will feel a difference.......just nothing earth shattering.

and rember that is flywheel horsepower not rear wheel horsepower.....your going to have to get more compression and good flowing heads and and exhuast worth a **** if ur gonna want real gains..... get some heads and exhaust and some comp and then we well tell u if u should go on up to a bigger cam or not.....get some double humps,a performer rpm intake, 2.25 or 2.5 exhaust and then we might step u up to the 268h high energy cam......maybe..... but with out those other things it would defeat the whole purpose in my opion......

Originally posted by SSMAN69:
You won't see big gains. Doesn't do a whole lot of good to put a good air/fuel pumping cam in with out using good heads,intake,exhaust. If you can't get the air in...........you can't get the air out. Don't get me wrong......you will feel a difference.......just nothing earth shattering. Well I have the exaust...my intake is a stock 4 bbl cast iron intake but I think I want to go to a Weiand aluminum intake....but what about the 882 heads? How well do they flow?

BTW I kinda don't wanna go into the internals of the engine as far as replacement (other than amybe a cam) as this engine is only going to be in this car until I can get a big block.

As far as the heads go, I'm not sure if it is Car Craft or Chevy High Performance that published a book (black cover, about the same size as many of the How to Rebuild ______ books.) It included quite a few SBC build ups, including a tear down of a Targetmaster 350 that ended up being lower CR than advertised, then they did cam swaps and intakes and such up til they swapped the heads and stuff.

Anyway, I think the last chapter was dedicated to chevy heads, stock, GM Hi Perf/Vortec, and aftermarket. They rated the 882 as the best flowing head in it's family. So its basically the best flowing head of that design/size/SMOG family, according to their flowbench testing.

Don't let anyone discourage you..go for the cam,intake swap and exhaust.

I assume this has as automatic with a stock converter. Take a look at the 4x4 cams also. XE254 4x4 will add just a tad bit more bottum, the XE262 4x4 will add a bit more top end. But if it were me, I wouldn't go above the 254 or 256 unless I had a higher than stock stall converter.

This one might be hard to beleive, but in the 383 that I built I used a Performer intake, Vortec heads, 1 1/2" headers, 2 1/4" exhaust going into 2 1/2" Dynomax Hemi Super Turbo mufflers and a XE250 4x4 cam. I installed it in my 1/2 ton 4x4, 3:08 gears, standard trans and 31" tires. It has a ton of torque right from idle and is still pulling hard at 4500. A small cam like this one would work just fine for a daily driver.

Brian

Originally posted by GRN69CHV:
I assume this has as automatic with a stock converter. Take a look at the 4x4 cams also. XE254 4x4 will add just a tad bit more bottum, the XE262 4x4 will add a bit more top end. But if it were me, I wouldn't go above the 254 or 256 unless I had a higher than stock stall converter. What stall would you recommend?

Also anyone know which 256 to go with? There's two different ones for sbc.