shootitup

Hi,

Our cc stinger 312 has two 454/330hp, wich we try to tune up lightly.

Other engine is orginal merc and other is 2001 marinepower.
Both engine has edelbroc performer rpm intake and stailessmarine manifolds with thru hull exhausts.
carbs are 650 holleys.

We think to change carbs 750-800, do the cam job and make something those small port heads..

Is the L29 Vortec head good choice for this or are there better low price solution.

Edelbrocks seems to go too high in price for two engines
in our budget.

Can those L29 Vortec heads even put in our engines ?

We suppose that bigger oval ports wake up engines for
better flow and rise the hp.

PatriYacht

Spend the money on the Edelbrocks. By the time you rebuild the Vortecs, the difference will be a lot smaller. The Vortecs are detonation prone and only flow about 2/3's of what the Edelbrocks do.

jeffswav

What year is the original engine? The 2001 engine should already have Vortec heads. If you can find a real good deal on them they will work. Just do not put more money into them than you could buy a set of good aftermarket heads for.

shootitup

[QUOTE=jeffswav;3190803]What year is the original engine?

I suppose that orginal are -86.
Orginal has been opened several times in time, latest last winter.

ezstriper

or if you could find some 781 factory heads, work great on boats, large oval port, match the intakes you have, and do change the cams and carbs

shootitup

Those 781 looks great, could be hard to find but if we find..

Also i have read procomp alu heads they are cheaper than
edelbrock..

jeffswav

Yep, 781's are good heads, I used the 820's because they have a smaller chamber. When I did my build I used flat top pistons so the smaller chambers up the comp. Get a custom roller from RMbuilder, well worth the $$$.

Itsallgood995

What heads do you have now...156's? I put a set of ported & flowed L29s on my gen V w/ good results. That being said, with what I had into them I'm not sure I would go that direction again. Don't count out the 156's for mild power increases. They will produce more torque than the bigger heads @ the lower RPMs.

http://cgi.ebay.com/ebaymotors/454-5...item41520868f6

I had this guy do my Vortecs but he has a lot of experience w/ making power out of the peanut ports.

shootitup

Dont know what heads are inside. Other engine is -86 mercruiser 7.4 and other is marinepower 2001.
Head change is in mind to rise the boat top speed. We get now 64mph in gps and try to reach 70.