ilovev8s

Hi, i am wanting to build a street motor, i am going to start with a 350 vortec most likely from a half tonne. Will be converting it to carb. To get in the range of 300-400 hp what will i need to do from the carb to the oil pan, im assuming i wont have to touch the bottom end to much. i was wondering what to use for carb, manifold, most of all what cam and compression ratio and how to set up the heads for this. Im new to engine building and all help will be appreciated, anyone that wants to post there carb vortec combos and hp numbers it would be greatly appreciated, thanks in advance

ilovev8s

come on guys, how should i put this motor together, need some help!!

3.8redbird

iTrader: (3)

crank or wheel?

crank a cam swap and your there.

rwhp your looking at some heads work or swap

Longtube headers, good intake, carb.

1.6+ roller rockers would help a bit too

3.8redbird

iTrader: (3)

crank or wheel?

crank a cam swap and your there.

rwhp your looking at some heads work or swap

Longtube headers, good intake, carb.

1.6+ roller rockers would help a bit too

welldonecj7

iTrader: (13)

Exactly as the above post said, it depends if you are talking crank hp or wheel hp. I would run the performer rpm air gap if I had a choice and wanted a good all around intake. With a different cam you can easily get the the 400 hp at the crank. there was a write up about this in car craft a while back, if you search their web site you can find more on that, they used a roller gm hot cam for theirs and it made right at 400, while still being streetable and making good vacuum.

ZONES89RS

iTrader: (25)

Stock 350 vortec with a cam and carb swap will make near 400 HP.

230/236 @.050 with 500ish lift on a 110 LSA, all you need besides springs.

brandoz28

iTrader: (3)

the GM hotcam works really well in these with some 1.6 rockers, or just get a cam with the specs that zones pointed out and then some 1 5/8's longtubes, and then a performer rpm air gap

blown94

iTrader: (1)

One VERY important thing you're ALL missing here,.......You cant get much over 480 lift I believe on stock vortec heads without swapping the correct spring/retainer combination or machinging the valve guide down. Look into it.

ilovev8s

ok my parts list will include from carb to oil pan, junk yard motor, carb, air gap, .500 lift cam, headers, valve springs, and I need to get the guides cut down, how much would the machine shop charge to do this and would they already know the proper height to cut them to, also would going bigger than 500 lift be better or is the a point where bigger would start to lose power?

brandoz28

iTrader: (3)

you don't want to go past .550, seems liek they stall out around there

and yes, you'll need to have the guides machined, and its not a bad idea to machine the pads so that you can run a bigger spring

ilovev8s

thanks for the info so far guys, so i was also wondering would gasket matching the ports of the heads and intake, and polishing the heads be worth it, is there much power to gain or should i leave them stock, also when do i have to start worrying about piston to valve clearance

ilovev8s

oh and one more thing, there is a 383 stroker kit around where i live for cheap, would i see much power gain throwing this into this motor??

3.8redbird

iTrader: (3)

383 kit will take machining and assembly so take that into the budget. But a 383 is a great engine. Although I may be biased

1994Z28Lt1

iTrader: (1)

unless you plan on using different heads or porting the heck out of the stock vortec's you WILL NOT make any more power than you would with a 350, however you WILL make it at a lower rpm.

You will also see when you get some intake gaskets for the vortec heads, gasket matching will be a non-issue. The gaskets are already larger than the ports on both styles of felpro intake gaskets that i have seen.

ilovev8s

but i thought gasket matching was taking away the metal of the ports until it was even with the gasket? but i think the engine will be potent enough as a 350, so will this setup be lots of power in say a 82-92 camaro or trans am, just wanting a little something for a good burnout, cut a few circles here and there and maybe some time a the strip, any estimate of end times on a well set up 82-92 with this type of motor,i know i know what tranny, suspension, tires etc but just looking for a ball park figure

ilovev8s

what do you mean when you say a cam with the zones pointed out, sorry but im still new to this stuff..

ilovev8s

one more thing, any opinions on a comp xe 268 cam in a stock engine plus the carb swap and headers

SuperSport01

From what i have read vortec heads dont flow after .520" lift without portwork. But there is some good info here... (http://www.chevelles.com/forums/arch...p/t-36483.html) (http://www.carcraft.com/techarticles...ade/index.html) (http://www.speedwaybids.com/tech/Vor..._Max_Lift.html) (http://www.chevyhiperformance.com/te...ift/index.html)

brandoz28

iTrader: (3)

here are a few articles using the GM hotcam
http://www.chevyhiperformance.com/te...ild/index.html

and another with an off the shelf comp cam
http://www.carcraft.com/techarticles...ock/index.html

ZONES89RS

iTrader: (25)

Well, i installed a XE288HR roller cam i my 95 Z28 with the SBC swap, with a performer intake and a set of cheap pace setter headers the engine chassis dynoed 311 HP and 245 TQ, so with long tubes and a performer RPM intake it would probably make closer to 350 at the ground. This was with a set of BS hyper flat tops with 4 valve reliefs.