A4 to A3 Swap guys in here!
03-05-2007, 02:17 AM
#34
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Found some info on LS1tech...
LS1 style engines to old style trans(th350, 400, 2004r, 700r4, 4l60e)
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here are the facts about fitting an old style trans to the gen3 engines
1. the gm gen1,2 trans will bolt to the gen3 engines but you only use 5 bolts, the gen 3 engines do not use the middle bellhousing bolt on the pass side( no big deal)
2. you do not need a special flexplate, the curved 4.8,5.3,LS1- just need the t/c bolt holes ovaled out a bit and the 5.3 flex plates have a set of holes that match the small gm t/c bolt pattern perfect
- the 6.0 flat flex plate has the same t/c holes as the large gm pattern(th400 and most aftermarket th350 converters that have a dual t/c bolt pattern on them)
3. you need to use a crankshaft spacer when using a gen1,2 trans and converter there are 2 types:
- hughes gen3 crankshaft spacer part # hup-3795, this spacer must be used with the curved 4.8,5.3,LS1 flexplates
- gm stock 6.0 crankshaft spacer 12563532 and longer bolts 12563533, this spacer can be used with either the flat or curved flexplate ( if using the curved style flexplate the flexplate goes on the crank first then the spacer goes on then the bolts, if using the flat 6.0 flexplate the spacer goes on the crankshaft first then the flexplate then the bolts)
LS1 style engines to old style trans(th350, 400, 2004r, 700r4, 4l60e)
--------------------------------------------------------------------------
here are the facts about fitting an old style trans to the gen3 engines
1. the gm gen1,2 trans will bolt to the gen3 engines but you only use 5 bolts, the gen 3 engines do not use the middle bellhousing bolt on the pass side( no big deal)
2. you do not need a special flexplate, the curved 4.8,5.3,LS1- just need the t/c bolt holes ovaled out a bit and the 5.3 flex plates have a set of holes that match the small gm t/c bolt pattern perfect
- the 6.0 flat flex plate has the same t/c holes as the large gm pattern(th400 and most aftermarket th350 converters that have a dual t/c bolt pattern on them)
3. you need to use a crankshaft spacer when using a gen1,2 trans and converter there are 2 types:
- hughes gen3 crankshaft spacer part # hup-3795, this spacer must be used with the curved 4.8,5.3,LS1 flexplates
- gm stock 6.0 crankshaft spacer 12563532 and longer bolts 12563533, this spacer can be used with either the flat or curved flexplate ( if using the curved style flexplate the flexplate goes on the crank first then the spacer goes on then the bolts, if using the flat 6.0 flexplate the spacer goes on the crankshaft first then the flexplate then the bolts)
03-05-2007, 09:02 PM
#36
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Originally Posted by jasond26
Well the truck is back on the road.......one word....AWESOME! I feel like I am driving a drag car. It shifts firm but not jarring. When you are on it and start hammering gears it feels badass. Not to bad cruising around at 60, I wouldn't want to go any faster than that for long periods of time though. I just got done with it so I will get some more driving time with it tomorrow.
When I measured the driveshaft it was 59 inches exactly from the face of the trans to the face of the yolk in the vertical position. It came out perfect.
When I measured the driveshaft it was 59 inches exactly from the face of the trans to the face of the yolk in the vertical position. It came out perfect.
Did the crossmember bolt right up to the truck and tranny? Pics of shifter and shift light install?!?!
03-11-2007, 03:18 PM
#38
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te Fbody crowd usually drops about 3-4 tenths from their 1/4 mile times due to the thm 350 having a lower parasitic drag than the 4l60e trans does.
Also the thm has a closer gear ratio spread and doesnt have as much shift extension like thewide ratio 700r4/60,60e,65e and 4l70e trans do.
A higher stall TC will help teh 700r4, 60e families big rpm drop at the shifts.
peace
Hog
Also the thm has a closer gear ratio spread and doesnt have as much shift extension like thewide ratio 700r4/60,60e,65e and 4l70e trans do.
A higher stall TC will help teh 700r4, 60e families big rpm drop at the shifts.
peace
Hog
03-12-2007, 11:11 AM
#39
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I'm almost done with my swap, and I encountered a few issues, but nothing I couldn't work through on my own.
First of all, do not round out or oval out the flexplate holes. That's a bad idea, especially if you're going to run a decent amount of power with a high stall TC. I went with ATI's flexplate, which is SFI approved, and it comes with the spacer shown above. TCI's is also a good choice and it too comes with the spacer. You put the spacer on the crank and then the flexplate, you bolt it on with longer bolts and that's it for the flexplate. Both TCI's and ATI's Gen III flexplates are flat and they come with a dual bolt pattern, so you can use an off the shelf TH350/400 TC. That's also why the spacer is needed.
I went with a JW Ultra Bell, because I like my feet/legs and I don't want to deal with the PITA a scattershield would provide. This caused an issue with the top 4 bolts that hold the rear engine cover on. They protrude out past the flange that the tranny bolts too. I had to hit the bellhousing a little with a grinder so they wouldn't hit. Also the Utra bell is designed to bolt to multiple engines, so the driverside "ear" needs to be cut of to clear a ground on the back of the engine.
My crossmember had already been modified for the T56, so all I had to do was add a 1" spacer to the top of it and bolt it down. If you don't have that luxury, then I would get a factory 5spd crossmember and add the spacer on top of that.
My biggest gripe is the ******* driveshaft. I have an extended cab, so I have a 2 piece. The driveshaft will need to be lengthened if you go with the short 4" tail TH400. No big deal, and I wanted to upgrade to 1350 u-joints anyway. My issue is that I wanted to run a thicker walled tubing so it won't twist up using the t-brake. Turns out that the diameter of our driveshafts is odd, and possibly metric, so thick walled tubing is costly. Also both ends needed quite a bit of machining, so what should've been a $150-$200 job turned into a $350 job.
I haven't hooked the shifter up, but the instructions are straight foward and it should be easy.
Oh yeah, go with Lokar's 36" firewall mount universal flexible dipstick. It's long enough so you can convieniently mount it anywhere and it looks good too.
First of all, do not round out or oval out the flexplate holes. That's a bad idea, especially if you're going to run a decent amount of power with a high stall TC. I went with ATI's flexplate, which is SFI approved, and it comes with the spacer shown above. TCI's is also a good choice and it too comes with the spacer. You put the spacer on the crank and then the flexplate, you bolt it on with longer bolts and that's it for the flexplate. Both TCI's and ATI's Gen III flexplates are flat and they come with a dual bolt pattern, so you can use an off the shelf TH350/400 TC. That's also why the spacer is needed.
I went with a JW Ultra Bell, because I like my feet/legs and I don't want to deal with the PITA a scattershield would provide. This caused an issue with the top 4 bolts that hold the rear engine cover on. They protrude out past the flange that the tranny bolts too. I had to hit the bellhousing a little with a grinder so they wouldn't hit. Also the Utra bell is designed to bolt to multiple engines, so the driverside "ear" needs to be cut of to clear a ground on the back of the engine.
My crossmember had already been modified for the T56, so all I had to do was add a 1" spacer to the top of it and bolt it down. If you don't have that luxury, then I would get a factory 5spd crossmember and add the spacer on top of that.
My biggest gripe is the ******* driveshaft. I have an extended cab, so I have a 2 piece. The driveshaft will need to be lengthened if you go with the short 4" tail TH400. No big deal, and I wanted to upgrade to 1350 u-joints anyway. My issue is that I wanted to run a thicker walled tubing so it won't twist up using the t-brake. Turns out that the diameter of our driveshafts is odd, and possibly metric, so thick walled tubing is costly. Also both ends needed quite a bit of machining, so what should've been a $150-$200 job turned into a $350 job.
I haven't hooked the shifter up, but the instructions are straight foward and it should be easy.
Oh yeah, go with Lokar's 36" firewall mount universal flexible dipstick. It's long enough so you can convieniently mount it anywhere and it looks good too.
03-28-2007, 01:10 PM
#40
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When you guys swaped in the TH400, did yall get a BRAKE and ABS light??? And what did yall do about the gear indicator? I left the little black box on there in park but on monday it was pouring hard and I think water got into it or something cause the truck thinks its in 2nd or 3rd gear sometimes. I couldnt start the truck twice so we had to override the starter.
We used HPTuners to disable the PRND321 but nothing happend, still shows 2nd gear.
We used HPTuners to disable the PRND321 but nothing happend, still shows 2nd gear.