The elusive 224/3.7 MerCruiser banger

Does a BBF (our 3.7) header fit if it is put on upside down. I'm thinking a cheap block hugger 460 exhaust header could be modified easily with a turbo flange if the header could be flipped. I didn't know if the bolts were centered in the ports. I can't just go look at mine since my A460 head has BBC exhaust ports.
Would the header clear the valve cover if it was upside down? It may take some extra slicing and dicing at the bends coming out of the ports?

 

spark plugs would want to be in same space and port not centered between bolts

 

Did you use a Word Class main case? What clutch did you use? What flywheel did you use?

 

tjm73,
It was a world class case. I already had the flywheel in my pile, it is an aftermarket steel one with a bolt on weight for a small block Ford, 157 tooth. I removed the weight and checked the balance, and it was good to go. The clutch, case and pressure plate all came from MDL. Paul recommended a dual lining disc, it is 10.5 dia. and as I remember was Kevlar on one side and regular martial on the other. I can look back and get numbers if you need them.

 

I would be interested out of curiosity. That clutch sounds very much like a typical 5.0 Ford setup, which would make sense given the transmission/flywheel configuration.

 

tjm73,
the case was listed as GM Muncie pattern WC T-5 case, I used a MD-900-2503-A hydraulic T/O bearing, CA70071 Pressure plate 10.4 dia, and KK-10.4-10 disk. This was all from MDL. To do believe it is all typical 5.0 stuff.

 

I have been following this thread since 2011.
I found a rebuilt 470, it is a short block needing to be and assembled but it is complete.
I am going to put it in a CJ-5 that has been a abandoned project.
The jeep has been converted into a sand buggy the 4x4 has been remove and a straight front axle with center diff rear axle.
My question is what is the simplest transmission to use?

 

These have a GM bellhousing pattern except for 1 bolt. The bellhousing is about 5/8" longer than the rear of a Chevy. Many guys take a cut off of the rear of the block to mount GM automatics. Look at the previous page for more information. There are ways to mount manual transmissions without cutting the block. Do you want an automatic or manual?

 

I would like to use a GM 350 , 400 or 700r.
It is a 170 with 2bbl would like to use the stock water pump with the truck manifold and a bolt on Alt.
Thanks

 

Where can I get this adapter?

 

Looks like a sprint car part. You'll want one for a Ford small block.

 

I found this one.
https://www.tsirace.com/product/rac...-crank-adapter-sleeve-small-block-ford-to-gm/
Can I use this with stock flywheel

 

The stock water pump would work, but I would be concerned about water leakage into the block like they are known for. There are some posts here about using a Toyota water pump on a home built mounting plate that would eliminate that concern. Glen Wilson has been using one for quite a while on his '32 Ford.
I don't know what you mean by "truck manifold"???
There are kits available to install the big GM alternators. I made my own mounts and installed a smaller Nippondenso
one. If installing a bolt on alternator I recommend removing the stock balancer and stator so you don't have to fight the loose magnets later. SBF balancers fit. A bolt on pulley is needed with a new balancer.

 

What does that adapter do?
I installed a manual trans behind my motor which required a pilot bearing bored into the crank.
I don't know what is needed in the crank for torque converter centering if anything. I had mocked up an automatic behind my motor and had just put spacers between the flex plate and torque converter. That did nothing to align the center of the torque converter. Is that needed?
I am planning an automatic transmission on the next one, so want to figure this out. If it was as simple as installing 5/8" spacers everyone would do that instead of machining the back of the block.

 

I do not want to put a Toyota pump on the seals will be new and I will watch for coolant from weep hole. It looks cleaner.
Truck Manifold for exhaust


That is for a GM Auto trans lifted from FB 470 site.
From BAD ZUK on this site:
I have a th350 bolted to the back of my 3.7. After much measuring and playing with flex plates and spacers and not having a solution I was comfortable with I simply made a bushing on a lath to hold the snout of the torque converter, and then drilled the stock flywheel with the correct bolt pattern for the converter.

So far it has worked well, I was worried about the excess weight of the flywheel and torque converter together, but the engine still revs up well, and on the low rpm it lugs along like a tractor.

I use this in my off road buggy, so it is not a screaming high performance drag machine, but it scoots along just fine.

Total cost? = about 10 minutes of machine time from a friend, and a 2" long piece of scrap tubing.

Having one of the best performing and most unique rigs on the trails...Priceless.
Also from this site:
A Flexplate off a 74 Maverick with a straight 6 fits nicely, and would work perfect by milling the block 5/8". You would still need a pilot adapter for the nose of the torque converter.
However in my case I didn't have the resources to mill the block, so I reused the stock flywheel off the mercruiser and drilled the appropriate pattern in it to bolt up the torque converter. The spacing was perfect, 1/8" between the two.
Then I just fabricated my own pilot bushing that indexed off the pilot in the flywheel.

Ford to GM Flexplate

https://www.tciauto.com/externally-...transmission-adapter-flexplate-50-oz-cpg.html

 

I am looking for the easiest way to a Auto trans mounted to the 470.
170 hp is plenty for my use just cruising around.
I do not want a multi year project.

 

Was this from a Ford truck? I haven't seen one like this. The collector outlet is shaped differently. I expect this is cast iron and heavy? Weight is my enemy.

The flexplate you have a link to will not work as it is. It has the counterweight welded on. That would have to be removed. I used this one which isn't counterweighted and is about 1/4 the cost. PRW Power 1830213 PRW Platinum Series High-Inertia Flexplates | Summit Racing

Does anyone have some drawings or dimensions of the required pilot bushing? Or a link to a commercially available one?

I like the idea of mounting the torque converter to the flywheel however for my usage weight is critical. I pull custom built 4 cylinder powered garden tractors. The total tractor weight has to be under 1150#. By the time the weight of the transmission and automotive rear axle is added it is getting heavy. This eliminates the usage of the stock flywheel. A Powerglide is lighter than a TH350 but 1st gear is too high (1.8 vs 2.52). Either low gear is slightly adjustable with mods (2.75 in the TH350). The torque converter adds considerable weight also. Currently I have a small manual trans mounted using a small dirt track racing clutch. I realize now my clutch isn't going to survive so am looking at the automatic.

 

You do realize how long these motors are right? If a BBF 460 won't fit lengthwise the 3.7 won't either.

I like your post about putting the torque converter onto the flywheel. If that works, I think it would be the easiest due to no block machining required. That flywheel is about 30# if I recall so it will take some of the vibration out of the big 4 cylinder. If reducing weight wasn't such a high priority for me, I would like to try that setup.

The GM automatic is the way to go for you, I think. No clutch linkage and easy shift linkage.

I'm guessing that you are going to keep the cast iron head also? I threw 3 of those away 2 weeks ago. I may still have a couple flywheels. If you aren't concerned about weight, use that "truck exhaust" manifold. An iron Mercruiser exhaust could have the water passages cut off, but it would give you a vertical outlet instead of downward. I have one of those done here if you want a photo. I see a lot of rat rods with their exhaust sticking up from the engine bay.

 

That exhaust manifold is from a HD truck (ie... dump truck).

 

Not worried about length there is plenty of room for the engine.


PRW Platinum Series High-Inertia Flexplates 1830213