300 for heads 615 to mod..... sweet vortec - priceless
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From: Tempe, AZ
Car: 92 RS, 02 Tacoma, 2 73 Porsche 914s
300 for heads 615 to mod..... sweet vortec - priceless
ok, bought some vortecs a while back on ebay for 300 for the pair having 45k miles on em. took em in to the machine shop, they put 2.02 intakes in, stock exhaust vavle job... screw in studs, new springs, etc... cost = 615 total with the new valves spring etc. btw, these springs are good to .600 lift
ahhh. someday
rockers were 356. LOL rockers were more than my heads... i just realized that. in all i have about 1250 in the complete heads now... they are teaming up with a performer rpm. powermax h290 cam on a 355.
question... how long will my stock tranny and rearend hold up with this engine
135k miles on em.


ahhh. somedayrockers were 356. LOL rockers were more than my heads... i just realized that. in all i have about 1250 in the complete heads now... they are teaming up with a performer rpm. powermax h290 cam on a 355.
question... how long will my stock tranny and rearend hold up with this engine
135k miles on em.

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Joined: Jan 2002
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From: Red Deer, Canada
Car: 89 Shortbox
Engine: 350 Vortec
Transmission: 700r4
Give the intakes a nice polish, and port those little exhaust ports.
And your 700 will probably last about 2000k like mine, 2-3 clutchs are mushy
And your 700 will probably last about 2000k like mine, 2-3 clutchs are mushy
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From: Chicago, IL
Car: 91 Camaro RS Convertible
Engine: 305 TBI
Transmission: 5-Speed
Axle/Gears: 3.42
Looking good you really can't beat that kind of price for some serious head (hehe). Are you planning on staying with TBI?
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Joined: Mar 2001
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From: MA
Car: 93 GM300 platforms
Engine: LO3, LO5
Transmission: MD8 x2
Polishing the intake valves won't help, other than help to retain combustioon heat -- and even that will be only a very small gain. But you should check to see if both the intake and exhaust valves are back cut (see either the Chevy engine book or the Chevy cylinder head book by D.Vizard), and I especially agree on doing mild porting on the exhaust. You don't need the shop to do these for you -- you can DIY them.
Since you don't have them installed yet, it's especially worthwhile to port the exhaust side, and leave the intake alone. There are numerous articles on the LT1/L31 heads and the common comment among them is that they flow extremely well (especially for stock heads), but the exhaust could use some help especially since you've added the big valves on the intake side.
How long will the trans last? IIRC it will last reasonably well if you don't speed shift. If you do speed shift, then you better start saving for the T56... because you will need it soon. HTH.
Since you don't have them installed yet, it's especially worthwhile to port the exhaust side, and leave the intake alone. There are numerous articles on the LT1/L31 heads and the common comment among them is that they flow extremely well (especially for stock heads), but the exhaust could use some help especially since you've added the big valves on the intake side.
How long will the trans last? IIRC it will last reasonably well if you don't speed shift. If you do speed shift, then you better start saving for the T56... because you will need it soon. HTH.
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