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97 SFA - Lexus V8 1UZ Conversion.... VVT-i vs non-VVt-i

Posted: Tue Mar 20, 2012 1:15 am
by Tumble
Hi All,
As stated in a previous related post on this forum... (See "97 SFA - Lexus V8 1UZ Conversion.... AUTO vs MANUAL")... i've taken the (mental) plunge and i'm doing it... that is - Converting my 97 SFA 2.8D DC Lux to a Lexus V8.
Yes - many, many questions and lots and lots of research - BUT - now i am happy with the decision, and surely the gods will smile upon my particular conversion job and i will emerge a happy man and proud owner of a fantastic new and revitalised '97 V8 Lux.

So - lets admit first of all - I am still not 100% sure on which variant of 1UZ-EF engine - but lets say i am 99.9% there ...and for the benefit of anyone considering going the same route, and for those who wish to add their experience, and tell me im making a huge mistake(!) - you are all most welcome - please post below ... :)

As far as the differences (as i understand them) between the Non-VVt-i and the VVt-i, ive added my 2c worth of PRO's vs CON's:
please feel free to rip it all to shreds... :)

Looking forward to hearing your comments...

Cheers
Jim
p.s. Final decision re VVT-i or non-VVT will be made by wednesday.

Pro's & Con's: Non VVT vs VVT

1UZ-FE Non-VVT-i
PRO's:
1. Cheaper as an initial purchase
2. Simpler - only 1 condenser per row (amongst other things)
3. condensers cheaper (R400 vs R1000 for VVT-i version)
4. if u go Spitronics - only needs 1 ECU module
5. lots of spares around
6. less programming on the ECU to worry about? (could also be a CON?)

CON's:
1. Less fuel efficient (slightly) - (see VVT-i Pro's below)
2. Less power & torque (see VVT-i Pro's below)
3. Older engine (1989-1996)

1UZ-FE VVT-i
PRO's
1. More fuel efficient - but only to the tune of about 10%, will need about 8 years to make up the difference in cost(!) (i am open to correction on this one... :) )
2. More power and torque (yeah - like you really NEED that extra 10% ha ha!)
3. Lots of spares around - and engine core is backward compatible with non-VVTi engines (not the head or the intake manifold though.)
4. Newer engine (1997 - 2002(?))

CON's
1. More expensive as an initial purchase
2. electronics more complex(?)
3. Condensers more expensive (see non-VVT-i PRO's above)
4. Has MORE condensers - (8 vs 2 on the non-VVT-1). BUT - that can also be seen as an advantage - if a condenser fails when you are FAR-AWAY and you forgot your box-of-spiders back home (FAR-AWAY), then u can still get home on 7 or 6 cylinders. (Not the same case for the non-VVT-1 which has 1 condenser per bank of cylinders.)
5. Needs 2 x Spitronics ECU (if this is your choice) - which also means you need 2 x Spitronics ECU carry-on spares in your box-of-spiders if you are going FAR-AWAY.)

Happy to hear you agree or rubbish my brief and admittedly possibly naive, analyses above. I can only learn!
cheers!
Jim

Re: 97 SFA - Lexus V8 1UZ Conversion.... VVT-i vs non-VVt-i

Posted: Tue Mar 20, 2012 7:19 am
by Stef
Jim,

By no means an expert, but my personal choice would be the 2JZ ;-)

As far as VVTi goes, I've heard from the drifting guys that one has to have the original ECU otherwise you can forget about even getting it started. How true that is I don't know first hand.

Re: 97 SFA - Lexus V8 1UZ Conversion.... VVT-i vs non-VVt-i

Posted: Tue Mar 20, 2012 9:37 am
by mark watson
stefan , there is no problem with the vvt and the spitronics , works well , but as for going with the 2j you must remember the 2j is 70mm longer than the 1uz and already it is a tight squeeze , and the 2j is a more expensive motor than the 1 uz non vvt , grantes there is nothing wrong with the j series motors but not in a 4x4 , bmw and the like yes they work like a bomb , have done the conversions already .

Re: 97 SFA - Lexus V8 1UZ Conversion.... VVT-i vs non-VVt-i

Posted: Tue Mar 20, 2012 10:13 am
by TheoM
AFAIK, the VVT-i has the OEM viscous fan and the motor is "slumped" forward requiring less firewall "convincing" in some trucks. That flat torque curve from 1000 RPM is very attractive in 4x4 application.

2c

Re: 97 SFA - Lexus V8 1UZ Conversion.... VVT-i vs non-VVt-i

Posted: Sun Apr 01, 2012 5:02 am
by kfxnando
sure this info could be too late, however pls allow me to still add fuel to the fire

non vvt, has distributors, distributor caps and plug wires, those moving parts somewhere along the way will always need attention

vvt, coil packs, less headaches, imo

as for the extra power of the vvt, as we are basically derestricting the motors from their original set ups, by running no catalytic converters and free flowing systems, then 10% and mire has already been gained, however the same could be said for the vvt, as those now sit in the same boat and have also gained from being derestricting

have fun :beach:

Re: 97 SFA - Lexus V8 1UZ Conversion.... VVT-i vs non-VVt-i

Posted: Tue Jan 20, 2015 8:55 pm
by Rian
Just something we have been playing around with. :boss:

https://www.youtube.com/watch?v=trWzSga ... 5JNFC4fvdw

Re: 97 SFA - Lexus V8 1UZ Conversion.... VVT-i vs non-VVt-i

Posted: Mon May 29, 2023 3:49 pm
by Koos Kiem
Jim,

I am reading your post, I want to do the same conversion. How did yours turn out?