351w Fresh Paint and Chrome Valve Covers!

DrCC wrote: I didn't think my hose was big enough. So, I had my 1" hose removed and put in some 1 1/4" hose.

That hurts just thinkin' bout it

My understanding is that measuring across the intake manifold, a 302 should be 9" wide and a 351 10 3/4" wide.

TRBenj wrote: Joe, I assume your concern would be any additional hose length between the pick up and RWP? If so, most of the time you can make the change without adding any length- just putting the trans cooler in line rather than running additional lines back to it. Conq/Crus used the same Sherwood pump design (slightly different case) as PCM, fwiw. OMC did use some oddball stuff (ours cross referenced to a Mercruiser RWP).

I am thinking the concern would be the pressure drop of the trans cooler. As long as it was the same cooler and the same pump between the two engines you can assume that you will probably live though. The added joints on the suction side are also places to pull air and possibly cause trouble. You want your leaks on the pressurized side if at all possible that way they are easier to detect and less likely to be of a critical nature.

None of it is likely anything to lose sleep about but I defintely see where the engineers were going when they were adding all that hose.

Joe, I assume your concern would be any additional hose length between the pick up and RWP?

If so, most of the time you can make the change without adding any length- just putting the trans cooler in line rather than running additional lines back to it.

Conq/Crus used the same Sherwood pump design (slightly different case) as PCM, fwiw. OMC did use some oddball stuff (ours cross referenced to a Mercruiser RWP).

I probably wouldn't change the non-pcm motors to the pcm routing, most pumps are much better at pushing than pulling, and some are worse than others at self priming. While a much simpler routing and we all know that it is tried and true with thier pumps and their engines what PCM is doing would not be considered best practice.

75 Tique wrote: My Chevy/OMC is plumbed through the pump first, then back through the trans then back up front to the thermostat.

Interesting, it's certainly not wrong I just haven't seen it done that way before. Seems like a lot of unnecessary hose though.

GottaSki wrote: One snapshot of where the distributor mates the block would also clinch it. If its fairly even with the valley, its a 302, if its about 3/4" below the valley, its a 351.

Agreed, doesnt look my 351. My distributor is much lower than that one, the top of the cap is much lower in comparison to the carb on mine.

Paul,
I don't have strainers on ANY of my boats and have NEVER had a problem. A lot depends on the water you run in!

GottaSki wrote: Alex47 wrote: 8122pbrainard wrote: ...you did use a marine pump rather than an automotive. Please, this is important - tell us about it. I just cleaned up the same fuel pump that was on the engine. Yes, the newer marine pumps look just like that.

I edited my initial post about 15 minuets after making the first one. I spotted the overflow tube!!   

8122pbrainard wrote: EDIT: Alex, I see the overflow tube now. It's pretty hidden - glad to see it on the engine!

eric lavine wrote: Sweet 302/351, you would be able to tell by head bolt size, one of the only physical ways to tell, except for dis-assembling and measureing the bores...there may be other ways, but this is the way that I can tell...i believe the 302 will be a 5/8ths socket and the 35i will be a 3/4 socket   7/16"ths bolt or 1/2" bolt

That's your inner chevy talking Eric...

The bores on 302 and 351 are the same.
So one would need to measure the stroke.

Yes, a head bolt would clinch it.

deck height and width are measurable externally.

One snapshot of where the distributor mates the block would also clinch it.
If its fairly even with the valley, its a 302, if its about 3/4" below the valley, its a 351.


Its also common to find 351 heads on the marine 302's, so anything written under the valve cover is suspect.

My eye also says 302.

Even the rear shot says 302. see how the intake is even with the bellhousing. It would be raised on a 351. This says the deck height is a 221/260/289/302 block.

A very good looking 302, well done

snipe wrote: Are you running straight exhaust? That has to sound great...

Straight exhaust with two hose clamps on each of the through hull fittings. Engine sounds awesome!

Nice job. Are you running straight exhaust? That has to sound great...

Sweet 302/351, you would be able to tell by head bolt size, one of the only physical ways to tell, except for dis-assembling and measureing the bores...there may be other ways, but this is the way that I can tell...i believe the 302 will be a 5/8ths socket and the 35i will be a 3/4 socket   7/16"ths bolt or 1/2" bolt   

Very nice job, Looks awesome.

Did anyone notice the water hose routing? Looks like it comes out of the RWP then goes back around to the trans cooler then back under the motor and up to the thermostat housing. Is that correct for this year? that should work but it seems like an aweful lot of hose.

sweet77 wrote: The valve covers say 351 high performance. where did you get them.

Here