mggdoors

Currently building 2 engines. 489 gen6 stokers. L29 heads pocket ported with incomes exhaust valves. 12551622 cams 224/224 .483 .483 lift. Air gap intakes. Holley 750 vac sec. Pertronix dist. Hge aluminum exhaust. Rod and main bearings are .002. Ring gap .018. How much power. Any issues?

mike tkach

iTrader: (3)

what boat will the engine be going in?if it is a performance boat i don,t think you will be happy,but it might work in a low rpm cruiser boat.as far as bearing clearances .002 is to tight for my liking and ring gap depends on what rings you use.their is no standard one size fits all with ring gap.

mggdoors

It's a Sunsation dominator 32. Won't spin more than 5200. It is twins. I

mggdoors

Also. I'm looking for 450 each. Nothing more. Figured I would be close considering 502 is 415 and I'm point higher compression with better intake etc

Panther

I've been going .003 1-4 mains and .0035 #5 and .0025 on the rods. Slightly less if the cranks were cut. That's been working well for me for a number of years.

.002 is definitely on the tight end of spec in my opinion.

What is being used for an oil pump? Is it a HV pump?

Panther

What rings do you have? Usually there is a spec sheet and it will tell you the gap based on your intended use and bore size. For instance, the last set of engines I did the ring manufacturer suggested .0055 X "Bore Size" for #1 Ring and .005 for #2.

GPM

I think you need a custom shelf cam with the new solid hydraulic roller lifters. Not really, but the cam may be a little small if you're trying to make 450HP. Just my opinion.

mggdoors

The pump I smelling m77 high volume. Rings are total seal. Call for .0175. I went 18-185.

mggdoors

My crank is new from scat. Do you think it will live at .0018 with only 5200 rpm. Why the difference on #5

Panther

It's always .0005 to .0001 larger on the #5. It's a wider journal and ground slightly smaller than the rest. I like to use Merc's Service Manual #3 to reference my specs when I'm putting something together. It's much easier than having to remember. The manual goes from the HP465 all the way up to the 800'sc. The Merc 525EFI runs a little tighter tolerances than what I've grown up using.