5.7 Merc Mods
 

Hi I'm putting a base 5.7 in my 19' Scarab and have seen some info on the web which states that I can get about 320hp with just using a 4 b carb, up-date the exhaust, cam and intake, I'll adviod pulling the heads-no grinding. I hope to be able to fit thru hull exhaust also.
I hear duration of 212-intake and 218-exhaust with 110 overlap and lift around .48-.5? I hear a flap tappet would be fine and I can pick up some more hp running a roller, would I have to swap springs or do anything else???
I'm not that up on this stuff so any layman terms would help.
I also need to order all this stuff, including manifolds, and have no idea how much it cost or where to by it. The exhaust will have to go in last as I need to see how much room I have. I'm building the motor hatch and rear seats afterwards so I've got some flexibility!
Thanks.

I'd put a 5.7 vortec in it....they make 300
hp.

Brand new marine 5.7 vortec long blocks can be bought
for under $ 3K., you'll need proper intake and carb.

You may need a different flywheel and coupler if older
than 86'

What he said especially if you don't have experience installing a cam.
You can get a complete carb to pan 320 hp eng. with ignition, spark plug wires and plugs installed for around $3700 delivered from 1800runsnew.com. No mess no fuss- rejet the carb, bolt on the exhaust, and accessories from your old motor set the timing and go.

Thanks guys, I'm getting the short block for $500, it's in great shape. I'm going to put the L 84 cam, mild mod, and look for a used 4 barrel intake then mount the motor in the 19' Scarab and I'll see how much room I've got to put thru hull exhaust in, so far I think the only area is right where the hull ID # is.
Oh, I'm also having the heads opened up a little.
I'm thinking that if all goes right, 4 barrel, heads, cam, & thru hull, I'll have a sloid 320 hp ?
From what I've been told the 19' Scarab has a good pad for speed?

what was in it to start with.

It had a V6, my friends motor fell thru as it had some water damage. I got another, 93 5.7 short block reman that was used only last summer and it has 4 barrel carbs, everthing except manifolds, for 2K and it's local.

Thanks to everybodies help here and at Scream I see that I'll be best to spend about 1500-2K more and get a reman. 5.7 Vortex that cranks a solid 320 hp! i'll drop a Enteria prop on it and I should be up to about 75 mph?

If it had a V6 in it it probably has a 1.84 or a 1.65
gear ratio drive in it,.....it would be in your best interest to
get a 1.5 ratio upper.

Yea i know, I'll look into it, thanks!