Small Block & Big Block Chevy SpecificMouse & Rat Motor Discussion & Conversions
Welcome to LS1Tech.com!
Welcome to LS1Tech.com.
You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join LS1Tech.com today!
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
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.
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.
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?
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
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.
__________________ 94 Z28 M6 3.73's 200cc AI h/c/i 228/234 614/614 forged 355, 11.6:1, Pacesetter LT's, ORY, Hooker aerochamber, SLP intake
Tuned by me
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
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.
BUILT NOT BOUGHT 80 Coupe 6.0 TH400 86 TA 5.3, 4L80 92 S10 ECSB 4.8 T56
Originally Posted by -Ross-
Haw mut horzpowa sbc or lsx eenjun mayk b4 eet need tarbo liked da 2jz?