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-   -   Vortec Heads on Pre 87 350's (https://www.offshoreonly.com/forums/chris-craft/167660-vortec-heads-pre-87-350s.html)

TAZMAN 08-31-2007 11:25 AM

Vortec Heads on Pre 87 350's
 
Hey do any of you guys know anything about putting the newer Vortec heads on the pre 87 SB 350s. I read the switch is pretty easy and gains 80 hp. I'm thinking of doing it to my 86 Stinger 260 w/ twin 350s.

Any real life experience to share?

Fenderjack 08-31-2007 12:45 PM

Yes you will def pick up power over what ya have now, I am pretty sure you will also need to change intake manifolds aswell..
John

BootyPirate 09-04-2007 05:44 PM

It is probably one of the easier ways to add horesepower cheaply. You will need the vortec manifolds as John said. Edelbrock performer will work good.. Make sure that you vortec heads from the same size engine you want the 64cc heads from a 350 and not the 58s from a 305. The compression would be too high with the 305 heads. Double check the cam lift I think there is spec somewhere that says the heads can't go over .490 but you may be able to chnge the rockers of pushrods to make it work? The vortec stuff will be all roller. Good luck. Sounds like a fun project.

Full Force 09-04-2007 07:40 PM


Originally Posted by TAZMAN (Post 2255416)
Hey do any of you guys know anything about putting the newer Vortec heads on the pre 87 SB 350s. I read the switch is pretty easy and gains 80 hp. I'm thinking of doing it to my 86 Stinger 260 w/ twin 350s.

Any real life experience to share?

80 hp? not from just heads, maybe with cams also. I used the edelbrock rpm's on my limited, with the vortechs needing different intake and rockers, and also needing spring work for more then 490" lift, the edelbrocks made more sense to me, I was very happy with the results.

TAZMAN 09-10-2007 08:19 PM

Good advice. I just found that GM is offering 383 SB stroker w/ 425 HP. Do you think my Alphas could handle that? I know Alphas are rated to 300-330 but that must be conservative. Seems like a deal for 425 HP at less than $5K each (need 2) if I don't need to upgrade drives.

Full Force 09-10-2007 08:23 PM


Originally Posted by TAZMAN (Post 2266160)
Good advice. I just found that GM is offering 383 SB stroker w/ 425 HP. Do you think my Alphas could handle that? I know Alphas are rated to 300-330 but that must be conservative. Seems like a deal for 425 HP at less than $5K each (need 2) if I don't need to upgrade drives.

They can last if driven properly, for sure do drive showers though.

ENGINESPLUS 09-10-2007 09:04 PM


Originally Posted by TAZMAN (Post 2266160)
Good advice. I just found that GM is offering 383 SB stroker w/ 425 HP. Do you think my Alphas could handle that? I know Alphas are rated to 300-330 but that must be conservative. Seems like a deal for 425 HP at less than $5K each (need 2) if I don't need to upgrade drives.

THE 383'S FROM GM ARE 340 HP 435LB TORQUE FOR THAT KIND OF MONEY I CAN GET YOU A 408 Chevy A-2 510 HP 500 Torque OR 383'S FOR UNDER 4000.00
OR BETTER YET MERC HAS 383'S COMPLETE WITH BROVO ONES TRANSOM PLATE STEERING MULTIPORT INJECTION THE WORKS DROP IT IN HOOK UP THE LINES AND PLUG IN THE HARNESS

TAZMAN 09-12-2007 08:48 AM

Do you "Engines Plus" have a web site? What is a 408 A-2? The Mercruiser 383 turn key w/ drive etc are more than $5...right?

BootyPirate 09-12-2007 09:23 PM

The 408 is a 350 block with 4" stroke. The A-1 is 470 HP/ 500Ft/lbs and the A-2 is 510 HP / 500 Ft/lbs. You can pick them up complete w/ Alum heads for around $4800. Add a carb and go. They are typically used in circle track or some of the different NASCAR series. So running all day at WOT is not a problem.

If you are looking for a short blocks or complete check out Ohio Crankshaft. They are about the best around.

psmith 09-13-2007 06:54 AM

Alpha's will not handel over 300hp, need to look at Bravo's and more money.


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