A750 tranny diesel - petrol differences

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Hi
Is there a difference between the diesel and petrol A750s like there is between the earlier transmissions?
My understanding is that there are usually more plates in the clutch packs in the higher gears in diesel version, however i cant seem to find any information related to this on the A750 - which sort of tells me that there isnt.
The reason im asking is that there are plenty of petrol A750s available at the local wreckers for reasonable prices but theyre asking stupid money for the diesel ones
I figured i could save some bucks using the torque conv and bellhousing off the a343 that i already have and get a petrol tranny
It is going to be mated to a 1KD

Cheers
Kris
 

GTSSportCoupe

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Easiest way to know is compare the two transmissions in the Toyota EPC drawings. They are hosted on the Megazip website. A750 was used with at least a couple diesels, so there might even be differences between those (1HDFTE and 1KDFTV). Best to look up the exact model vehicles to know for sure.

Is that a compound turbo 2LT/3L in your picture? I'd be interested to learn more about that! What sort of fuel upgrades have you done? I find the 10mm pumps are pretty limited. Always thought a 12mm pump from a 1KZTE would be a nice upgrade.
 
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Easiest way to know is compare the two transmissions in the Toyota EPC drawings. They are hosted on the Megazip website. A750 was used with at least a couple diesels, so there might even be differences between those (1HDFTE and 1KDFTV). Best to look up the exact model vehicles to know for sure.

Is that a compound turbo 2LT/3L in your picture? I'd be interested to learn more about that! What sort of fuel upgrades have you done? I find the 10mm pumps are pretty limited. Always thought a 12mm pump from a 1KZTE would be a nice upgrade.
Hi,
Have you got a link to those spec sheets? It only comes up with Suzuki stuff in the search.

And yes, thats a compound 3L, it is running a 12mm plunger boost compensated pump and the fuel injectors were opened up as well.
 

GTSSportCoupe

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Hi,
Have you got a link to those spec sheets? It only comes up with Suzuki stuff in the search.

And yes, thats a compound 3L, it is running a 12mm plunger boost compensated pump and the fuel injectors were opened up as well.



Did you ever dyno your compound 3L? Must go good!
 
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Did you ever dyno your compound 3L? Must go good!
I dynoed it last year just after putting it together, it was only running 28psi at the time on the fresh engine. Manual transmission. Made ~460nm at the wheels from 1700rpm with a small decline all the way to the redline with injection timing retarted to max factory setting and EGT not exceeding 650deg, ~26 Afr. Very safe tune. Later I turned up the boost to 40psi, the gearbox gave up 2 days later, now im on fully manual control A343 which seems to be holding up alright when locked up. Im in the process of replacing the compound setup with a gtb2260 off an x5 bmw because i cant make use of the low down torque with any of the available transmissions. And later on relacing the 3l with a 1kd.
Cheers for the link
 

GTSSportCoupe

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I dynoed it last year just after putting it together, it was only running 28psi at the time on the fresh engine. Manual transmission. Made ~460nm at the wheels from 1700rpm with a small decline all the way to the redline with injection timing retarted to max factory setting and EGT not exceeding 650deg, ~26 Afr. Very safe tune. Later I turned up the boost to 40psi, the gearbox gave up 2 days later, now im on fully manual control A343 which seems to be holding up alright when locked up. Im in the process of replacing the compound setup with a gtb2260 off an x5 bmw because i cant make use of the low down torque with any of the available transmissions. And later on relacing the 3l with a 1kd.
Cheers for the link

That is very impressive! Good work. I can't say I know anyone else who has pushed an L series motor that far. Have you documented the build process anywhere? I would be interested in reading if you have something on another forum somewhere. You must be around 600-650nm at the flywheel at this point? That's quite incredible for a little old IDI diesel. Same power per liter as a 900-1000nm 1HZ to put it into perspective!

That amount of effort into the 1KD will have ridiculous results. :oops: Now I understand why you're interested in the A750, haha.
 
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From what i worked out from the spec sheets, the diesel is different part number but doesnt show the internals so im not sure in what way, it could be just different sensors. The oil pump and torque converter assembly appears to be the same which is quite surprising knowing that the diesels usually got lower stall speeds. I beleieve the oil pump would be different too on a diesel to provide higher pressures on lower rpms.
Im gonna ring up some wreckers and try to get them to put the diesel torque conv on the petrol tranny, if it physically fits it cant be too far off.
If i can get my hands on a diesel tranny, which would my preferred way because ive got more car parts in the shed that i know what to do with, ill post my findings, i beleieve theres enough info on his forum about the petrols to make a comparison

Regarding the build, ive got some pics on instagram, same username as here. Im happy to answer questions or do a write up if youd like. Its not too fancy just something ive worked on during the lock down last year. All done on the cheap.
 

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If you have the cash you could always ring up or email Wholesale Automatics in Australia. They will get you a 750 ready to rock and roll.

If you sit down in front of an EPC like at Megazip and open up petrol and diesel side by side. I would think in less than an hour you will have most of your answers.

Cheers
 
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Unfortunately EPC doesnt have any info on the internals. I spent my last night there. Or i just wasnt lucky enough to find that :)
Im in australia, i can just pick one up for a diesel from the wreckers but theyre usually $2500+ whereas petrol ones go for $200-1000. Low stalling a torque conv would cost approx $300 so the whole project could be pulled out a lot a cheaper if that was the only difference.
None of the repair manuals suggested that certain models would have different number of plates like on the a340s
 
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alright boys, a little update, ive been browsing partsnavigator.com.au for some time now (that site has got all the part numbers of the internals) and heres what ive found:
  • petrol and diesel uses the same oil pump and input shaft
  • they have the same number of clutch and brake disks
  • the only difference in part numbers is direct clutch piston and 1st brake disk - the part numbers are adjacent in both cases so i guess theres not much difference
  • the torque converter is definitely different along with the flex plate
  • a340 torque conv is not likely to work although i have a torque conv out of a KZN '94 Surf that lines up with the KD flex plate but this probably wouldnt help anyone as these cars are non existent outside of Japan and Oz
  • diesels got an extra spacer around the flex plate
based on this im quite confident that a petrol tranny would work on a diesel given the right torque conv and bellhousing are used

im gonna get it running with an a343 and try to find a good deal on a petty a750 while im setting up the ecu for the kd and then ill get into making a controller for the a750

but
dont hold your breath
 

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