Build Ed’s Un-Did FJ40

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You might want to drop the tub and tranny hump on it. The po's mechanic installed my sbc/nv4500 setup. He placed the engine so the nv4500 shifter was located in the tranny humps stk hole with very slight alterations. The sbc looks spot on under the hood.
 
pb4ugo said:
You might want to drop the tub and tranny hump on it. The po's mechanic installed my sbc/nv4500 setup. He placed the engine so the nv4500 shifter was located in the tranny humps stk hole with very slight alterations. The sbc looks spot on under the hood.
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I would if it was an option. The tub isn’t here out at my shop. I do at least, have my 40 here for some general comparison.

His tub was a 3 on the tree originally so the trans hump is going to get a fresh hole wherever things land, plus the additional for the AA twin stick.

I’m trying to avoid having a rear driveshaft that’s ridiculously short as I’ve been down that road before.

Any idea how long your rear driveshaft is with your setup?
 
My d/s is really short, but works great. I bought the 40 in 96, so it was an early conversion kit. Its a 1st gen GM nv4500. As far as tell, it was b4 AA casted the 5th gear housing to adapt to the tcase. So the trans output shaft and housing is stk length with the tcase adapter behind it. When I looked at the 40 I wasn't intending to buy it. I wanted to drive it and checkout the conversion setup. Once I checked it out and drove it, I had to buy it. The mechanic/installer did a nice job with a lot of intention to detail and the 40 was in great shape. Your setup should be a lot shorter, you should be fine. If you want to see pics or measurements for engine placement, let me know.
 
pb4ugo said:
My d/s is really short, but works great. I bought the 40 in 96, so it was an early conversion kit. Its a 1st gen GM nv4500. As far as tell, it was b4 AA casted the 5th gear housing to adapt to the tcase. So the trans output shaft and housing is stk length with the tcase adapter behind it. When I looked at the 40 I wasn't intending to buy it. I wanted to drive it and checkout the conversion setup. Once I checked it out and drove it, I had to buy it. The mechanic/installer did a nice job with a lot of intention to detail and the 40 was in great shape. Your setup should be a lot shorter, you should be fine. If you want to see pics or measurements for engine placement, let me know.
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Ok, yeah, the newer adapter from AA that I’m using is much shorter than the OEM rear extension housing. So that’ll help. I’m just shooting for a rear driveshaft that’s ideally at LEAST 24” long. Even with that, it’ll likely need a CV on the transfer case side.
 
The goal is to push the engine nearly as far forward as possible to the fan, probably within 1/4”-1/2” off the water pump which is the longest part on the engine. Which is why I’ll need to collect a few more body parts to verify where the bib actually lands
 
My driveshaft is 18" long flange to flange with a 4" skyjacker lift. The driveline is 37 3/4" long measuring from the frt of the bellhousing to the d/s flange on the E brake drum. The 40 uses the AA style motor mounts with the rubber pucks, with the 90* gussets welded to the frame. The center hole of the mount bracket is about 9 5/8" from the rear shock tower top rivet. The frt top edge of the frame mount height is about an 1 1/8" above the frame. I run the long water pump with a 1 1/2" fan spacer, the fan is 2 3/8" from the radiator. The guy moved the radiator support bracket to the passenger side to help center the fan in the stock fan shroud. The fan is a cheesy plastic flex fan cut down to about 17" to fit in the shroud. It suprisingly runs real cool with no issues. I can almost run an 18" fan. The trans is pushed up about as high as it can be without contacting the tranny hump. They used a hammer on the hump to gain some height. I wish they would've used a rubber mallet. Im not sure it made a difference. They used the stk shift boot mounting holes and made the hole larger. There's not really anything I see that I would change with the position. A common area to look at on sbc conversions is the relationship between pass side exhaust crossover pipe and the frt diff/U joint area and or the frt pulley and diff housing on high suspension flex.
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pb4ugo said:
My driveshaft is 18" long flange to flange with a 4" skyjacker lift. The driveline is 37 3/4" long measuring from the frt of the bellhousing to the d/s flange on the E brake drum. The 40 uses the AA style motor mounts with the rubber pucks, with the 90* gussets welded to the frame. The center hole of the mount bracket is about 9 5/8" from the rear shock tower top rivet. The frt top edge of the frame mount height is about an 1 1/8" above the frame. I run the long water pump with a 1 1/2" fan spacer, the fan is 2 3/8" from the radiator. The guy moved the radiator support bracket to the passenger side to help center the fan in the stock fan shroud. The fan is a cheesy plastic flex fan cut down to about 17" to fit in the shroud. It suprisingly runs real cool with no issues. I can almost run an 18" fan. The trans is pushed up about as high as it can be without contacting the tranny hump. They used a hammer on the hump to gain some height. I wish they would've used a rubber mallet. Im not sure it made a difference. They used the stk shift boot mounting holes and made the hole larger. There's not really anything I see that I would change with the position. A common area to look at on sbc conversions is the relationship between pass side exhaust crossover pipe and the frt diff/U joint area and or the frt pulley and diff housing on high suspension flex.
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Ok, some of those measurements are certainly going to be helpful. I appreciate the help. I agree, the passenger side starter/slave cylinder/exhaust outlet/front driveshaft area is my biggest concern for clearance. I think we’ll likely have to use the AA bellhousing also which puts the clutch slave on the drivers side., guess we’ll see tho
 
@pb4ugo that’s a very clean looking 40 you’ve got there too 👍
 
My slave is on the drivers side. Im not sure what b/h was used.
 
Rock40 said:
@pb4ugo that’s a very clean looking 40 you’ve got there too 👍
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Thanks, I wasn't intending to buy it, but when I saw it i had to. A sometime in the future I'll be changing the driveline and going to a Dana 300 tcase and centering the rear end. It should shorten and strengthen the driveline a ton.
 
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pb4ugo said:
My slave is on the drivers side. Im not sure what b/h was used.
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Almost certainly the AA conversion bellhousing then
 
peesalot said:
Generally is the LS larger than an old school sbc ? I mean the basic block & heads.
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Depends on what size LS but generally I’d agree “yes” they are a bit larger. The 6.0 is significantly larger than the ‘96 Vortec 5.7 it replaced on my own 40. Where I had ample firewall clearance with the 5.7 at the rear passenger head, the 6.0 LS was now about 1.5” into the firewall
 
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peesalot said:
On my 40 I’m running fairly simple Daystar Stinger bumpstops front and rear. That said, the rear is a 4 link in Currie TJ coils and the front is 5 link on coil overs. Bump stops have held up for nearly 15 years tho, I’ve replaced a few cushions over time. My wheelbase is about 102”
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Funny, I been hunting a set of those, spoke to Daystar this morning, NLA, they lost their microfiber producer. I think I found a set of NOS in Florida but we'll see if they ship, I am surprised that there isnt a similar product on the market. I know the TeraFlex are microfiber as well but they dont have a universl application , only Jeep replacements.
 
peesalot said:
Funny, I been hunting a set of those, spoke to Daystar this morning, NLA, they lost their microfiber producer. I think I found a set of NOS in Florida but we'll see if they ship, I am surprised that there isnt a similar product on the market. I know the TeraFlex are microfiber as well but they dont have a universl application , only Jeep replacements.
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Interesting, good to know I guess and kind of bad news.
 
The Daystar guy said he had a set on his TJ for 15 years and the interior rubbers have held up fine, no splitting or deterioration which is a good long term review IMO. He did say that Daystar is looking for a manuf. for the rubbers & will resume production if they find one as they have a niche product with no competition.
I have spoke with numerous people lately expressing dismay with air/hydro bumps and looking to switch, most end up on Timbren parge soft rubber bumps, I am hoping to go your route, fingers crossed. Curious, do your rear bump cans sit below frame or did you build up a contact pad off axle, I got 11 inch between bottom of frame & axle tube so either I hang them down and fab mounts/bracing
 
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