Vortec 350, how to achieve 300-400 HP??
#1
Vortec 350, how to achieve 300-400 HP??
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
#3
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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
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
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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
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
#5
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.
#7
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
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#8
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.
#9
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?
#10
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
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
#11
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
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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.
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.
#15
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
#16
what do you mean when you say a cam with the zones pointed out, sorry but im still new to this stuff..
#18
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)
#19
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
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
#20
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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.