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Old 05-22-2022, 12:12 AM   #1
Keith6987
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How far can I move the engine forward?

I’m just getting started with my power/drive train mock-up on my Blazer 4x4. I don’t have any of the original parts, so I don’t know what stock looks like. I’m going with an NV4500 with a NP241C trans case and a small block. With the engine and transmission crossmembers in the stock position, the trans mount holes are 3 1/4” to the rear of the trans. crossmember. I have heard of people moving the engine forward 2”, but is 3 1/4” too much. I plan on using an electric fan setup. Are there any other clearance issues I’m not anticipating. Also, is a 4 degree tilt to the rear a good number to shoot for? Thanks, Keith
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Old 05-23-2022, 09:28 AM   #2
hemi43
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Re: How far can I move the engine forward?

The first thing you need to install is the transfer case. Everything else is located off of it.
As far as the 4 degrees, this is not a number to just guess at. The engine MUST be the same angle as your pinion angle, and you want around 3-4 degrees of angle in your U-joints.
Oil pan clearance is the reason you can't move the engine too far forward, so make sure your pan is on during mockup.

Install the transfer case, install the rear diff, install the rear driveshaft and the rest will fall into place.

Edit; I just realized you're using an NP241. My info above was if you used the original transfer case and it's factory mounting points.(Not sure why you would use the 241)

Last edited by hemi43; 05-23-2022 at 09:39 AM.
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Old 05-23-2022, 10:43 PM   #3
Keith6987
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Re: How far can I move the engine forward?

Thanks for the reply. I don’t have any of the original drive/power train. I do have an NV4500/NP 241c passenger drop. I don’t plan on any heavy off road use, so a 205 TC isn’t really needed, and I didn’t think it was worth buying adapters to make it happen. The NV4500 and NP241 are made to go together. My research indicated that the SM465 was 19 1/4 long and The NV4500 is 20 1/2, so I thought 1 1/4 would be no problem to deal with. Fabrication is my strong point, so I can remake the side mount to fit the 241. I thought I would move forward at least 2” since it is common with the 700r4 swap. Then I would get a drive shafts made to fit. I know I’ve got a big can of worms.
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Old 05-24-2022, 09:41 AM   #4
kwmech
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Re: How far can I move the engine forward?

Most of the moving forward I have done entails the engine x-member moving on the drivers side to the next forward hole, then drilling the pass side to match. At this point you can use the 2wd fan shroud and throttle cable. If you are going with electric then your only concern would be the trans shifter interfering under the dash or the oil pan, and then of course a lot more custom parts. Oil pan not a problem if you have at least a 4'' lift. Don't use the 205 side mount on the 241. The 241 has/had a rod that goes up to a bell housing bolt
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Old 05-24-2022, 01:37 PM   #5
JJH Jimmy
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Re: How far can I move the engine forward?

Since you are using a small block i would keep the engine on the stock crossmember and move the trans mount back. you want the engine as far back as you can get it for ride and handling.
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