Build my twin 350 tempest for my z29

[DAULEY]

I do have a budget they are 300hp now would like 400+ hp .Can anyone help

[BigGrizzly]

Realistically you need more like a 383 like the Poodles. I talked to a Nascar engine builder and boat freak, he pulled a dyno sheet on that combo, it had gobs of torque (450#) with just under 400HP. He told me that to get a real 400HP you will have to spin it over 6,000. The dyno sheet showed torque dropped after 5,200. In short use the torque and prop it for it. This will give you less strain on the engine and drive components. Scott is free with his information and will help.
With that big of a boat this would be my choice. I know someone will say that they can get 400HP out of the 350, but the engine will be nasty at slower speeds, and tube headders will be a must.

Randy

[DAULEY]

what would you do to motors cams heads ect
thanks

[EricG]

Since no one else has mentioned it....you may want to consider your drives before you start building the monster SBC's....according to your profile - you've got alpha's, which are considered sketchy above about 350HP...just a thought.

I'm casually watching the Z29 market so I can move that direction in a year or two....I know when I move up, I'll consider a relatively stock setup with alpha's, but if the motors have been modded, I'll probably look elsewhere....I've got an alpha now in front of a stock '88 350 Mag and it makes me nervous.....just something to consider.

EG