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Is there a date stamp on the block, or do I just go by the plate on the door? And yes it is a 5 Speed with the high comp pistons and d shaped runners.
 

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well, i only have 4 front lower timing covers. none of them have the 6m on them. though i think at least 2 are for 7m's, they all seem to have the same size hole for the crank pulley to go through. ill measure them tomarrow, right now im just too tired to go that far into it. thinking of throwing together a stockish 6mge for the 85 since i have all the parts. 20 over 7m block, good std crank, std bearings. 20 over domed pistons and rings, several spare heads, though ill p&p one before it would go on. stock 6m crank pulley, etc... im going to use the 7m ati damper for my weber 6m build, and prolly forged pistons in a custom compression with eagle rods.
 

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I'm in the process of building a Franken-6 using a 7MGE block. I'll be running OE 5MGE electrics, injectors, and intake (1985) along with a Pacesetter header and CAI. I've heard that some people have issues with the engine leaning out after 4500rpm. Has that been solved? I've done a lot of reading about the process and have the block stripped and honed, with new pistons, rings, bearings, etc on the way. During all this reading I've come across a few notes about Knock Sensors being different between the 5m and 7M, and wonder if this might be a source of any ignition or fueling problems if I use the 7M sensor with 5M ECU.

Also, is there any difference in the heads between 82 and 85 (valve size, cam profiles and timing, head gasket design)?
 

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Was that an early 5m pickup Manvir? I don't recall having that problem, I ran a late 5m pump.

Rev, no major differences in the heads, but lots with the intake of course. You should be fine with all 5m electronics, just make sure you don't use the factory pacesetter 02 sensor bung. The sensor needs to be directly in the exhaust stream. You will likely run rich like most every 5m with a header and boltons does.
 

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That cover info made me curious. I just had to pull the lower rear cover off my 6M because of a water leak due to a crap gasket. I checked my 8/84 built 5M and it had the smaller hole outer cover as expected. But I was very surprised that its lower rear cover had the larger hole for the 6M crank nose. Checked the EPC and indeed all "85" 5M's do. That changeover happened 8/84. More good info to know. Yeah, in both cases, it would have only taken a few minutes to clearance either cover. But now we know which ones don't need it.
It was also a good opportunity to fix an oil leak due to a crap Tennessee gasket. All the seals were fine but having everything this far apart, I replaced both lower seals. I thought it was strange that the 6M had a 5M crank pulley. Fortunately, I had both seals on hand.
It also has a cork oil pan gasket. WTF???
So, in case anyone is wondering if the lower rear cover can be removed and replaced without removing the head or oil pan with the engine in the car, WITHOUT any leaks, the answer is a definite yes! I was lucky in a sense as removing the cover didn't result in any damage to either gasket. I very slightly beveled the top and bottom rear edges of the cover to make it easier to reinstall without damaging either gasket. Yes, it's a very tight fit. But I aligned it perfectly and gently persuaded it back into position without damaging anything. Ok, the gently part is a bit of a lie. I had to carefully pry it off with 2 pry bars. Once I had it far enough on to be past the lead edges of both gaskets, I used a small dead blow hammer with a wooden block to "assist" it all the way back on.
I coated both the rear cover gaskets, Tennessee gasket and the front of the undamaged farging cork oil pan gasket with a very thin coat of Ultra gray after thoroughly cleaning every surface with acetone. And I reapplied FIPG at the top rear of the cover where it meets the block and head. I let the whole thing cure for a day and then added the oil and coolant. It's been 2 weeks and no leaks. Yeah!!!
As there's always been minor leaks around the oil pan and it has a pretty significant dent where the drain plug is, if I decide to drop the pan to take care of these issues, it'll be pretty easy to attach the cradle to hold the engine in place and drop the subframe like I did when swapping in a completely upgraded and modded front suspension, steering rack, brakes, Celica struts and steering arms and the 5 lug stuff. At least I now know why it's the way it is. Maybe I'll be lucky when I decide to drop the pan and the farging cork gasket will totally stick to the pan and not the block. Any bets?
 

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I'll bet you a 5 pack that the gasket WILL BE stuck to the pan and not the block,Ray.(You keep one)
"Drop the pan" is a major ordeal. I did that twice in 2 months.:32:

While the pan is out,see what the oil pump screen looks like. Got sludge?
Weld up the oil pan after beating it into submission?Save the 1/4 turn drain plug,if possible.(I like mine,totally)

Like Tanya once said,"the 6M is a unicorn", all by it self. Just left over parts from the '84-'85 5MGE'S.
Then, we all say WTF?
Ray,I never see you ever post photos. Is that because you have a MAC?
 

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Discussion Starter #51
I have the same water leak behind the lower rear timing cover. It's been leaking for almost 2 years now, finally it's gotten to the point I have to put 1/2 gallon in every day (fill resevoir and top rad off). I am not taking any chances with head gasket sealing there so I am pulling the entire engine for a re-seal since it's been 9 years (on 4/20!) and she's got a multitude of oil seeps

I wish my engine had made it 10 years before doing this but oh well. Most other people's builds from around that time have already blown up so I can't complain too much XD
 

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I didn't see anyone posting up what belt to use with a True 6M, 6M timing Gear and 7M Supra crank pulley. I used a 4PK0925 which is a 4 rib belt. I wanted a 900(90mm long) or maybe 910, but the local shop had a 92.5mm belt in stock. This was with a 6M alternator(5M should be the same I think). It was a little on the long side, right about at the end of the tensioner, but it might actually be a good fit for both a 5M and 7M alternator in the 5M location maybe?(I didn't try to fit a 7M alt) I used a 4 rib belt not a 5, as I am driving it off the AC belt spot on the 7M Crank Pulley seems to line up well.
 

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For those curious and since I cannot find anything on it.

6MGE with 83 electronics: AFR runs 14.5 to 15 cruising. Off throttle engine braking is also 14.5 to 15. Doesn't seem to lean out as in the injectors stay closed.
 

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That's interesting. Just keeps burning fuel during decel? First efi car I ever heard that does that.
 

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Hi Guys, back again.
About to take on a 6m motor swap in a barn find MK1. Wish me luck. I'm beyond scared... LOL.
Gonna start with a gasket kit and take my time (hopefully).
 
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