Trying to get a hp/tq est

[aft3rsh0ck]

I know you guys are pretty smart.
I have a list of parts im tossing on my bone stock 350 sbc. Could you guys give a rough estimate of my hp and tq ill be looking at?

Cam is 234/244 @ .050 duration .488 intake lift .510 exhaust lift, timing set is a double roller timing chain and gears, heads are 1998 chevy vortec 305 heads 520 casting number, 1.84/1.50 valves, heads milled to 56cc combustion chambers, positive valve seals, Z28 springs with dampener removed to clear guide, top of guide machined down to accept more lift, 3 angle performance valve job, valves back cut 30 degrees, edlebrock 700 cfm carb, and edelbrock performer intake, and a decent set of shorty headers

Thanks a ton!

 

[seawolf18]

What are you using for a rear gear and stall? That cam seems alful big for a 350 street engine, especially with 305 heads on top. The vortec 305 heads don't flow as well as the 350 vortecs, but they are better than the 305 HO heads found on the 80's Monte SS. For that cam to work on the street you would need around 4.11 gears and a 3000+ stall. The cams power band probably doesn't start til 3000 rpm as well. You probably won't have enough vacuum for power brakes either. Your heads won't be able to breath enough to take full advantage of the cam. Bigger is not always better when it comes to cams. It needs to match the parts you are using. As for power, around 300HP with a properly matched cam. I would look at a comp XE262H or XE268H cam. The 268H is advertised biggest for stock converter, but it runs better with a 2200-2500 stall.

 

[aft3rsh0ck]

for now just my 10 bolt with posi 373s. Fall I was going to tackle the rear end and trans. I was thinking of running a 2500 stall

 

[seawolf18]

with 3.73's and a 2500 stall, I would seriously consider using the XE268H cam. The driveabily on the street will be much better, and it will still have a nice lope to it.

 

[aft3rsh0ck]

thx for your imput man. really appreciate it
could you let me know what the biggest concern is now with the parts I have?

thanks again bud

 

[Blew86442]

As seawolf stated, that is a lot of cam. Also, I would think that your carb is too big. For that cam an rpm performer intake would be better too, followed by a higher stall, etc...it all daisy chains off of one another. You have to have a pretty good understanding of how all parts work together. What compression are you shooting for?

Too big, or too much of one part and not enough of the other and your performance is going to suffer drastically.

I have a friend that doesn't understand this. He keeps telling me how this engine he picked up has this wild cam and is going to be this street monster. Well he doesn't have anything else to back it up with. Sorry to say, but the car isn't gonna be all that impressive.

 

[Jshock]

That setup will work but not very effectively. Once you get on the pedal, she'll fall flat on her face. Too much cam with not enough flow and an over carbed intake will kill you once you get off the idle circuit. Also as previously stated, you will have almost no if any engine vacuum, so unless you run a vacuum pump you lose power brakes and you'll lose the vacuum used for your timing advance too. If your running a th350 trans, you won't have the vacuum to the shift modulator either. I'd recommend getting a set of 350 vortecs with at least 1.94's or better yet 2.02's. make sure your springs can handle the cam lobe lift. And if it were me, I'd follow those fellas advice on the cam, it will save your project for only a couple hundred

 

[Randy_W]

My single biggest concern would be the heads, they are not nearly the same as 350 Vortecs, they use and impediment to start the swirl unlike the 350 heads, and next the cam is way too big for the combo. I'd rather have stock cleaned up 350 heads than the 305's with all the work and the 268 cam is a great choice. But the heads are still going to be a fly in the ointment.

 

[seawolf18]

Guys would bolt 305 heads on a 350 back in the day to get the compression up in the late 70's -80's low compression smog engines. They get the compression up, but the poor thing can not breath. Try breathing through a short garden hose while running around the yard. Thats basically what your engine will be doing. It will start the run out of breath at around 4500 rpms. The trade off is more torque due to the short runners and more compression. Like the other poster said, I would sell those heads to some one, and either get a set of 350 vortecs or a set of L98 aka 350 TPI heads. Your carb is also pretty big. I would shoot for a 650CFM carb. The 750 edelbrock can work, if you change out the metering rods and jets so its not so fat in the fuel department. I would also run a performer RPM intake instead of the performer. The performer works well for a stock engine, a RPM breaths better in the upper revs.

I do have a set of 305 HO heads on a 350 in my 80 chevy pickup. When I pulled it for a rebuild one of the heads was cracked, and a I had the set sitting here. I pocket ported them and put them on my 350. The engine also has just a Melling MTC 1 RV cam it in. Works perfect for an old pickup, low rpm high torque (under 5K) pulling stuff, and getting through snow drifts in the winter. For a stop light to stop light hotrod, that is not the set up you want.

 

[pontiacgp]

There are 5.7 vortec heads out there, I got my set fully dressed for $300 and that's the cheapest hp gain I have ever found...