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Re: Lexus 1uz-fe v8 conversion

Posted: 06 Mar 2018 23:46
by Alex Roux
Malcolm

That would not have been Patrol gearboxes?
I have never heard of a Patrol gearbox burning out. Many Lexus boxes yes.
I cannot comment on Chevy conversions as I do not know enough about them, but from personal experience, my Lexus with bell-housing and Patrol box gave me many good miles and memorable trails & trips.

Re: Lexus 1uz-fe v8 conversion

Posted: 07 Mar 2018 05:01
by Peter Connan
If I remember correctly, one of Malcolm's primary objectives when converting his GQ was to get a way from the standard auto box, so he did use the Lexus auto box.

Strangely, I have only ever come across one guy who doesn't hate that box. Chris Boegman loves it!

Re: Lexus 1uz-fe v8 conversion

Posted: 07 Mar 2018 08:31
by Alex Roux
Peter Connan wrote: 07 Mar 2018 05:01 If I remember correctly, one of Malcolm's primary objectives when converting his GQ was to get a way from the standard auto box, so he did use the Lexus auto box.

Strangely, I have only ever come across one guy who doesn't hate that box. Chris Boegman loves it!
I think the problem with the older Patrol auto boxes was lack of power from the TB4.2 and TB4.5, rather than the auto box itself.
In Boegman's case he has the TB45 inside the GQ body and a fairly light one at that. So it does not hunt gears.


Also, the Lexus box, unlike the engine, is not strong enough for 4x4 applications.
I cannot imagine how much it would struggle with a Chevy v8.
Personally I would not consider any conversion of a Patrol unless it retains the Patrol gear box.

Re: Lexus 1uz-fe v8 conversion

Posted: 07 Mar 2018 09:05
by mvcoller
My problem with the standard box was that the ratios on that 3 speed box was all wrong. Max speed in 2nd was about 110 kph, while the 3rd gear ratio was so long, I could not maintain 120 kph on the road in top gear. The revs were just too low, so it had no power. It was happy at 140, but that was not practical. At 110 in second you were doing nearly 4500 rpm (red line was at about 4300 or 4500 IIRC), and once the box changed into 3rd, revs would drop to 1900 rpm. At 120 KPH the engine revs were at 2100. The 4.2 motor did not have any power at 2100. It thrived from 2500 rpm upwards.

Both the Patrol and Lexus boxes were Aisin (or something like that) boxes, so they were from the same factory. The Lexus box was a 4 speed auto and the ratios were much better. Regarding the burning out of the boxes, they were connected to the standard Patrol auto box cooling circuit (bottom of the standard radiator). That turned out the be the problem. It did not cool the box sufficiently. The box and tunnel got so hot, you could not touch the floor of the vehicle. Fortunately Lexus boxes were cheap (R1,200 each) and labour to fit it was R1500. It was more expensive to tow the dead Patrol to the mechanic that it was to replace the gearbox. The inconvenience factor also did not go down well with the missus when the Patrol gearbox problems happened, once in Volksrust and once north of Pretoria.

After the last box burnt out, we fitted a separate bigger oil cooler and that was the end of my problems.

After that the vehicle went well and although I never found someone that could satisfactorily tune the Lexus motor (Spitronics) I got fairly good consumption at 8.5 km/lt on the open road. The low RPM problem persisted though. Even the Lexus wanted to rev about 500 rpm higher @ 120 kph. I actually looked into changing diff ratios to a 4.5 diff from the standard 4.3 diffs, but that would have been very expensive.

Had I fitted an American V8, which generally is much better at low RPM, the Patrol would have been perfect.

I eventually sold the Patrol after I retired as I could no justify owning 3 Nissan 4x4s. Us pensioners need to count our pennies.... 3 x licences, 3 x maintenance & services and 3 x insurance payments quickly eat your money!! :rolling:

Re: Lexus 1uz-fe v8 conversion

Posted: 07 Mar 2018 11:20
by Tinus lotz
If money is a problem just put in a tb42 it wil bolt in and will cost you less than 20k done....

Re: Lexus 1uz-fe v8 conversion

Posted: 07 Mar 2018 12:34
by Wilkie
Tinus lotz wrote: 07 Mar 2018 11:20 If money is a problem just put in a tb42 it wil bolt in and will cost you less than 20k done....
And fit a later model 4 speed auto box to that TD4.2 (R3000..its eating space in my garage).. :rolling:

Re: Lexus 1uz-fe v8 conversion

Posted: 06 May 2018 21:02
by Reenen
Wilkie wrote: 07 Mar 2018 12:34
Tinus lotz wrote: 07 Mar 2018 11:20 If money is a problem just put in a tb42 it wil bolt in and will cost you less than 20k done....
And fit a later model 4 speed auto box to that TD4.2 (R3000..its eating space in my garage).. :rolling:
Is dit n patrol auto, en het jy dit nog? If so, I want..

Re: Lexus 1uz-fe v8 conversion

Posted: 06 May 2018 21:08
by Reenen
Ek is besig met n paar v8 conversions.

1. 351 Cleveland met sy ford 3 spoed auto, op n safari onderstel met 4.88 ratios, onder n 1979 Buick lykswa met 35" bande.
Ek hoop die ford 3 spoed sal cope met die 4.88 en 35".

2. Safari, 4.88 ratio, met vk45de(heel moontlik supercharged) op td42T gearbox en of 31 of 33" bande. Ons kyk na tussen 290kw en 350kw, en 510-750nm op wiele. Hoop die patrol box n diffies gaan dit handle. Kar weeg n skamele 1700kg.

Re: Lexus 1uz-fe v8 conversion

Posted: 07 May 2018 06:20
by Alex Roux
Daars baie goed wat kan breek in so ‘n setup, maar ek sou reken die Patrol diffs en rat kas staan die laaste in die ry van goed wat gaan/kan breek.

Re: Lexus 1uz-fe v8 conversion

Posted: 07 May 2018 08:03
by Wilkie
Reenen wrote: 06 May 2018 21:02
Wilkie wrote: 07 Mar 2018 12:34
Tinus lotz wrote: 07 Mar 2018 11:20 If money is a problem just put in a tb42 it wil bolt in and will cost you less than 20k done....
And fit a later model 4 speed auto box to that TD4.2 (R3000..its eating space in my garage).. :rolling:
Is dit n patrol auto, en het jy dit nog? If so, I want..
het hom nog ...3.0l complete