Big inch four: Mercruiser 470/485

[jamesdfo]

Well, lately I have stumbled across threads where the Mercruiser 470/480 engines have been mentioned, and only this evening finally found mention of someone who has actually run one (Randy Dupree) ( and @ Bonneville, no less
So, after a quick PM asking for more info, I suggested that my questions be answered here, in a post so that others may also benefit from any info.
Here's what I know so far: Built by Mercury Marine from approx 1978? to about 1984?.....aluminum block, using Ford "385" series (aka: 429/460) cyllinder head. 470 version was 2bbl, w/170HP rating, while the 485 was 4bbl w/180HP rating.
Here are some things I'd like to know:
1)How practical is adaptation to a STREET driven car?
2)What bolt pattern is the back of the block?
3) How much parts interchangeability is there with a 460 Ford (ie: connecting rods, main/rod brgs, etc?
4) If #3 is none, are the mercury parts still available and affordable?
I'm sure there is more to ask, but that's a good start

PS: If there are any errors in the above info, let me know and I will edit!

Thanks in Advance to Randy for taking time to respond.
James

[KY Boy]

This will be a great thread if we get some replys. I alwas wanted to put an aluminum cj head and go all aluminum on one.

[JohnEvans]

Well what I know/found out !! The back of the engine is CHEVY ! bellhousing and crank flange is standard Chevy, so easy hookup to common parts. Now this is what I've been told crank is special to this engine , pistons,rods, head 460 Ford. Have heard problems with having iron head on a aluminum block ,heads cracking. Seems you couls fix that with a aftermarket aluminum head. I found out about this engine after my T was setup for the ChevyII style 4 banger other wise I proubly would have went with one.

[dutchtreat]

The best head to use would be to run an Edelbrock 429/460 head. I think you will have to redo the waterpump setup as it's setup to run-outside water-lake/river. There use to be an aftermarket 4 barrel intake for this engine--almost bought one a few years back. Would make a great Track T engine.--Good luck
Dutch

[bigblock225slant6]

hmm, now im going to keep my eyes peeled for marine engines

[jamesdfo]

here are some older threads I just found with a bit more info....I will add any others as they turn up

http://www.jalopyjournal.com/forum/s...ght=mercruiser

http://www.jalopyjournal.com/forum/s...ght=mercruiser

http://www.jalopyjournal.com/forum/s...ght=mercruiser



James

[bigblock225slant6]

you know, Ive been looking at some of those high horsepower big outboards and wondering if there was a way, but im not sure if Ive got it all figured out yet.

[Phil1934]

Originally Posted by JohnEvans

bellhousing and crank flange is standard Chevy,

Crank flange is neutral balance 289 or 250 six

[tjm73]

Originally Posted by JohnEvans

Well what I know/found out !! The back of the engine is CHEVY ! bellhousing ....

well...not exactly Chevrolet. It is very close to the Chevy pattern I've heard compared to a barn shape. A dowel pin or two doesn't line up according to my research on this same topic. Also the Chevy starter will not work. You need either the original starter (may or may not work) or I have read that an International Harvester V8 (70's era) starter will work.

One other thing on these engineis the alternator. The OEM unit is built into one of the pulleys (crank if I recall) and is prone to failure and is realitvly low output. There are, however, automotive style alternator kits. I bit pricey but a permanent solution to the issue.

There is yet another thing to be cautious about. Something to do with a seal on the cam failing and causing problems. But I am not not up to speed on that issue.

[tjm73]

Originally Posted by Phil1934

Crank flange is neutral balance 289 or 250 six

To clarify that's 289 Ford or 250 I6 Ford.

The 300 Ford I6 is neutral balance and may also be a source for a crank pulley. This is a total hypothesis on my part though.

[bastard]

This thread is going to be good. I am working on two of them right now. Both with boos 429 heads.

I have been looking for info for these motors for a while and there isn't much out there. From what I have seen the bell housing will bolt up to a chevy but there was one whole that needed to be moved I think I will check again when I get to the shop. The rods I pulled out of the two I have both were cast with the 429 cobra jet part numbers. The cranks in these things are really heavy. I just got mine back from the machinest where we were able to take about ten pound off of it. Also we turned down the rod journals to accept chrysler rods. The hardest thing for me to find right now is some one to build me a cam shaft.

Keep the info coming.

[hotrodjohnny77]

In stock form, junk junk junk junk junk! I am a master certified Mecrcruiser tech for 12 years now. Prone to blown head gaskets, cracked heads, poor charging, bad ignition etc. Is and was a problem child from day one. Please pm if you need any specific info, be glad to help.

Jon

[Phil1934]

Just send the cam for a regrind and add adjustable studs and rockers. Starter is 392 IH, but not obtainable, so best to stick with Mercruiser. The owner of http://www.innovationeng.com/ had a Jon Kaase built Boss headed BBC rodded stroker Mercruiser in a dragster. There is an extended bellhousing so he can do a flywheel if you need. If auto you can just shim.

[JohnEvans]

Well I guess I stand corrected!! Got my info from Phoenix area midget guru Dave Ellis who first told me about this engine. Interesting engine none the less.

Bastard try Delta Cams ,have had good luck with them.Running a 350 HP Chevy grind in my 153 now and got to order the same for the 181 I'm now building.

[jamesdfo]

Originally Posted by bastard

This thread is going to be good. I am working on two of them right now. Both with boos 429 heads.
Keep the info coming.

bastard: PICS!!......we need PICS!!! (I've got my own kleenex)

James

[jamesdfo]

Man, it amazes me how many alias' there are for this engine!

Mercruiser 470 / 485 / 488 / 170 / 180 / 190 / 165
...and I know from the bit of digging I have done that they started around 1978, but this link tells me they went later than I had previously believed (1989?)

http://www.sterndrive.info/sterndriv...0_180_190.html

....and here's another with even more alias'
http://www.jasperengines.com/pdf/37L...IgnitionTB.pdf

...and this one has parts diagrams (broken out by years/serial number ranges)
http://www.perfprotech.com/store/cat...nder,3172.aspx


James

[Wesley]

Here are some things I'd like to know:
1)How practical is adaptation to a STREET driven car? I finished a rebuilt of my friend/neighbors 32 roadster wiyj on of these engines. You would be suprised at how much power that thing makes and how easy it is to drive on the street in a light car.
2)What bolt pattern is the back of the block? he was using a turbo 400 behind the engine. If I recall correctly the 2 top bolt holes had to be modified the dowel locations and the 4 nolts around the dowels were run as is.
3) How much parts interchangeability is there with a 460 Ford (ie: connecting rods, main/rod brgs, etc? About the only thing that is Ford is the head. If I recall corectly the crankshft is from a britsh leyland tractor and everything else is unique to the mercruiser.
4) If #3 is none, are the mercury parts still available and affordable?
I'm sure there is more to ask, but that's a good start Parts are still available from mercruiser and are priced right up there with aviation parts. There are still a few marine mechanics that will work on one of these engine, however around here most of the dearships dont want to know about them. Just so you know even though it was marine engine it ran a closed cooling system so if you find one that was run in salt water is should not be a problem.

PS: If there are any errors in the above info, let me know and I will edit!

Thanks in Advance to Randy for taking time to respond.
James
PM me if you need more info, my friend still has this car and lives 2 blocks away from me, I can get more info from him. Another friend who is a marine mechanic used to work on these engines, I dont know if he still does, but I am sure he has not forgotten anything, I could ask him questions as well.

[bastard]

Originally Posted by jamesdfo

bastard: PICS!!......we need PICS!!! (I've got my own kleenex)

James

There isn't much to take pics of right now. Just got the rocker arms in And the pro charger for one of the motors. Next we have to get the valves and springs here then port the head. These heads are costing me a fortune so I have to buy the parts slowly. I will have about 4 grand in each head when they are done. Hope to have the motors done by end of the winter. Should have the chassis for the anglia that on motor is going in done by then also.

[stude_trucks]

" the 485 was 4bbl w/180HP rating. " ??

I don't know jack about these motors or pretty much anything, but do I have this correct?: 485 ci with a 4 bbl carb and only 180hp made in the 70's and 80's and this is an interesting motor for some reason?

I must be missing something about this. Maybe 485 cc's?

[jamesdfo]

Originally Posted by bastard

These heads are costing me a fortune so I have to buy the parts slowly. I will have about 4 grand in each head when they are done. Hope to have the motors done by end of the winter. Should have the chassis for the anglia that on motor is going in done by then also.

Bastard: What got me going on the 4 cyll research in the first place is my vision of a super-light, 4 cyll Thames delivery.....so I would be interested in seeing what you are putting together......have you posted anything in other threads ( this thread may not be the place, but I would definately like to see what you are working on

James