Marks V8 Adapter: Motor Mount placement

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eperry0303

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I know there are a couple of V8 threads out there, but I am wondering specifically about the Marks adapter which allows you to keep the rest of your drivetrain untouched.

Anybody have photos of the Marks adapter in a 55? Specifically the placement of the motor mounts in relation to the shock towers, and thier motor mounts? The Marks kit comes with the V8 mounts, not sure what they look like, where they get welded up on the frame.

I have a 79 55 with stock PS gear, and don't want to move it if I don't have to, so want to make sure I get the right setup for the conversion....
 
Howdy! I'm surprised that nobody with a 79 v-8 conversion has piped up on this, although it is rare, and the Marks Conversion kit is twice as rare in the U.S. Steering box clearance issues would be the same, with or without power steering. I can't really help on this as mine is AA mounts, with a Ranger Underdrive for the conversion to H42, and custom mounted Saginaw PS box. Good Luck. John
 
inkpot said:
Howdy! I'm surprised that nobody with a 79 v-8 conversion has piped up on this, although it is rare, and the Marks Conversion kit is twice as rare in the U.S. Steering box clearance issues would be the same, with or without power steering. I can't really help on this as mine is AA mounts, with a Ranger Underdrive for the conversion to H42, and custom mounted Saginaw PS box. Good Luck. John
Click to expand...

Still no luck on the Marks stuff, but with AA motor mounts, what bellhousing adapter did you use? I used to have a 40 with a 350, and things were pretty tight against the firewall, and as I didn't do the conversion myself, I don't know if the transfer case mount had to be messed with or not.

I want to keep my 4 spd, not move my drivetrain. Can I do this without the Marks V8 adapter? I'd be curious to see what you have, how it looks at the firewall, etc.

Thoughts? Pics?
 
Howdy! I used a Ranger Underdrive to match my 350 to the original H42 4speed. I moved the drivline back a bit, but kept it under the tunnel so I can keep it tucked up high. With the parking brake right at the rear of the tunnel, it places the engine a bit more forward that I would like. I don't have room for a clutch fan on the water pump. I did my SOA with custom shock towers long before I did the engine swap, so I don't remember much detail of the original steering box setup. I run a Saginaw PS that came with the doner engine. John
 
I don't have the answer, but I know there was an issue with the Mark's kit when IPOR installed my V8, so they went with the AA kit. Thinking about it, shifter placement was going to be the issue with the H55 Trans. But if you want the true facts
call Lance Williams at IPOR, he can give you the info. Based off the info I got from Advance Adapters, that's the direction I wanted to go but Lance said it would not work with my setup.


Lou
 
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Marks & H55

Lou,

I also posted this on your build thread but how much length difference and shifter location difference on the top plate is there between a H55 and a stock four speed? I'm just trying to figure that in as to why the Marks was not needed with your build. The fit was evident in the pictures of your build when the engine and the H55 went in.

Thanks,
 
Adapter

OK I have some clarification on this issue. First off (thanks to Lou) I was able to find out from Lance at Ironpigoffroad that a Marks Adapter will work fine in a 55 with the stock 4-speed and a V-8. The reason Lou did not need one is that he used a H55 5-speed and the shifter is in a position that worked perfect without it (check out his build). Anyways, I guess we'll find out soon enough since I have purchased a Marks and I will soon be purchasing motor mounts and a rear crossmember for a 55 and the fun begins! I'll try to take pics as I go and see how it comes out.
 
Marks

Another point that has been brought out was why use the rear crossmember if you are going to also have the brackets mounted to the bellhousing to the existing frame mounts. I also posed this question to Lance as to whether it would be overkill to have both. He said it would not be overkill. I guess the sturdier the better. I'll most likely be using both.
 
mtrdud said:
Another point that has been brought out was why use the rear crossmember if you are going to also have the brackets mounted to the bellhousing to the existing frame mounts. I also posed this question to Lance as to whether it would be overkill to have both. He said it would not be overkill. I guess the sturdier the better. I'll most likely be using both.
Click to expand...
Howdy! I used the 3 point mounting system when I did a 350/ NP465 in my FJ40. I really liked it. I used the motor mount that fit across the front of the engine instead of the stock Chevy side mounts. The old style truck bell has mounting tabs on the sides, so I rigged them up like the Chevy side mounts, and then I used the standard mount on the rear of the transfer. Never had a motor mount comes loose or a bushing wear out. John
 
Marks Adapter

I got my Marks Adapter today thanks to a fellow mudder. I'm still gathering parts for the swap and I'm getting fired up and ready. I hope to be pulling the 350 out of the donor soon. I'll post pics as soon as some actual work starts.
 
Hey mtrdud,

Any progress on your project using the marks adapter? Really curious to see how this works out, as this is the setup I am leaning towards, although I'm probably 6 months away.
 
Marks

At the rate I'm going it may be 6 months before I get started (I hope not). I'm still gathering parts. I have the Marks, just got some rear mounts, bellhousing should be here tomorrow. I still have to get motor mounts, rear crossmember, clutch, pressure plate, and throwout bearing. The only obstacle now is a little $$. I'm running sort of low on cash so I'm having to buy a few parts here and there. Hopefully when the ball gets rolling I can make some progress. I'll post some info and pics as I go.
 
55

OK, here's an update. Set to be delivered tomorrow by UPS: (purchased from Georg (OrangeFJ45) and he saved me some $$. AA motor mounts, AA rear crossmember, Centerforce clutch, pressure plate, TOB. I'll still need a flywheel but I'm buying that locally next week. Front motor mounts are cut out and ground down to a clean frame (no turning back now). I'm off all next week and the fun will begin! I'll post some pics soon and especially of the "mock up" of the Marks/motor/transmission.

Also, I think I remember that Lou used a Manafree radiator. What are some other options you guys used? I have a used OEM 55 radiator but I'm skeptical about it's condition.

:clap:
 
mtrdud,

I'm jealous you are getting started now! I'll be keeping an eye out, and thanks for keeping us in the loop on this. I'm curious about a few things, and you are really paving the way for this setup. What flywheel/cliutch, where the GM motor mounts end up in realtion to the shock tower/PS box are of extra special interest to me.

BTW, what SBC are you going to put in? I'm starting to source 2000 and up Vortecs locally, I think I'm going to go that route, likely a 5.3 L.

Watching with great interest!

Eli in Boise
 
55

I will be using a Centerforce Clutch and Pressure Plate. I still will need a flywheel because there is an automatic transmission in it now. I will be using what is "supposed" to be a 87 350 that originally came from an IROC Camaro with low miles. I have yet to get to the casting numbers to verify but it does run great at any rate. I have a Saginaw PS box and I'm curious as well as to what relation everything will be with the steering. I guess we'll see. I also have the Marks Adapter in hand so there is no doubt that this is going to happen one way or another!. I "believe" that the motor mounts will end up being behind or more towards the rear of the vehicle in relation to the shock mounts. Yes, there are some unknowns with this but at least you have the benefit of seing how I come out with it. It should be fun!
 
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