VVT-i with a turbo?

[jibbby]

Wondering what the draw backs of owning a VVt-i motor when trying to boost it?

I have a friend that is selling a completely stock 98 SC400 VVt-i with decent miles on it and is considering trading straight up for my 1992 SC400 and a few extra bucks.....I am considering the offer...

Can anyone tell me what I am looking at when trying to modify the 98 models?

 

[Lextreme II]

Perhaps you can donate your 92 SC400 Lextreme Foundation for Research and Development? There are two issues you have to over come.

1. VVTi engines are not good for FI (weak rods)
2. VVTi and ECU issue.

 

[jibbby]

That's what I remember reading about these newer vvti motors... I drove the 98 around yesterday and just love it...It's decently quick at stock too.. With all the basic N/A mods I could really get that SC moving...Still need boost though for sure....A little gutless off the line as well...

Boosting it looks like trouble for sure, and a weaker motor to boot.... Man that sucks...

Lex, As far as donating my 92 SC4 for research and development....sure the car still needs lots of developement and just little research...Why not...

Thanks Lex for the reply, so you would advise against the trade swap? Those 98 Sc400's are really a step up in class from even a showroom 92 SC400...

 

[Lextreme II]

Sounds like a good plan.....

 

[Toysrme]

AFA vvt-i itself. There isn't a drawback with a turbo. The turbo is going to follow & enhance the output of the engine in it's N/A form & because the vvt-i itself isn't introducing large amounts of overlap that would blow the charge back out into the intake port - tada!

 

[jibbby]

So Toys - Which would your rather prefer to have, an early model 1uz-fe motor non VVt-i motor or a newer 1uzfe VVt-i motor to boost in your ride?

 

[Lextreme II]

Personally I would put in either Argo rods from Rods (Zuffen) or H beam with good strong forged pistons...... and boost until you get tired..... That would be the ultimate.

 

[jibbby]

Lex, Isn't that what you have in your boosted LS400 now?...I think you have the Ross pistons in if I remember correctly...How is that motor doing these days, did you ever fix the head gasket problem and tune that baby yet?

 

[Lextreme II]

The LS400T is running very well. Driving almost daily (Previa and LS400T) I put back stock injectors right and stock ecu for Smog check and will be installign 550 cc injectors along with a new standalone computer (Adaptronic) very soon and get that baby professionally tune. I am aming for 500 rwhp.

 

[jibbby]

500whp with your LS400 tranny could spell disaster...You may want to re-think your goals with that Lexus transmission...No? Unless your final torque numbers are real low, I would not try that...

 

[WDoherty]

jibby, i would take it, transfer your headers, exhuast, torque converter, and get an srt intake with built in ecu and you should be at about 345hp and i'm guessing mid 13's, add your nos to that and maybe mid 12's and be happy with that unless you really have that turbo bug, then this car could get really expensive.

 

[WDoherty]

oh yeah, your tt auto lsd also. But anyway, i'm guessing he would want your car as is and it would be a biatch to remove all that stuff and put it on your new car and you might be better off switching to tex long tube headers as well.

 

[WDoherty]

also, it really depends on what's most important to you. You seem to like the sc body and you want to go fast in it, is that what it is? Or do you just like the 1uz? If you want to go fast economically and then a 5 speed sc300 is the ticket. If you like the newer body style and want a newer car go for a 97 5 speed. Seriously though if budget is a concern its the way to go a 98 sc400 wil probably be double the cost and having to build the engine, then transmission issues on top of that. Club-nat.com has $1299 t-61 turbo kits, then add yourself centerforce clutch, and some sort of ecu, (map-ecu, aem for na supra) and your done. Those kits are good for around 440rhwp or about 540hp crank on pump gas at 18psi. (for that level add injectors, fuel pump, and headgasket). After that your pushing the w-58, switch to the r-154 or v160 and basically its how far you want to go as far as hp. Anyway, just thought i would share some options as i'm not sure what you goal is, but it seems like you like sc's and you want to go fast. If you are sure your not going turbo, i definately get the 98 sc400 and with those mods i'd think you might be able to hang with the is350 all motor, which is quite a feat.

 

[jibbby]

Well WD, it's not that I am in love with the older SC body style but I still like it...I also like going fast and being comfortable doing it at the same time...Hence the SC's..

Well after cruising the 98 with 63,000 miles I found that it was a very nice ride, alot of newer toys and gadgets then what's in my 92, and decent N/A stock power with VVt-i motor...Almost as fast as my 92 without the nos.. He likes my clean 92 with it's looks and power of course...So him and I was considering the swap straight up... I do have the boost bug for the SC's so I was looking to upgrade to the newer model and boost it...Unfortunately the trade is car for car and an additional $1000 cash, oh and I can't remove anything, rims, headers, LSD, etc..NADA....

Anyway, got too much invested in my SC now and don't want a weaker tranny, and motor with more trouble to boost.. Also don't want to give up the $1000 because of the mods I would have to buy afterwards...So I guess I am out on the deal, but it is oh so tempting after driving the 98......End of story...

If it was a clean Supra TT (6 speed manual) I would have had to say goodbye to my SC but just can't do it for a stock 98 SC400...

Thanks for all the input...

 

[Lextreme II]

How much is your car worth and now much is the 98 SC400 worth?

 

[jibbby]

My car is not worth much if I were to sell it, that's for sure, and the newer 98's are relatively rare and still pricey...That's was my delema in this decision....

Dollar for dollar on the market the 98 is probably worth more then twice as much..It's always hard to get a good price even for a super clean and upgraded older mod'd car....I am currently into my SC4 for almost $20,000 now including the purchase price of $8500.. Pound for pound my car looks better on the outside and is faster and handles much better... On the inside the 98's are very clean and upgraded and an absolute joy to drive.. I just can't do it, my older SC is still pretty much in showroom condition in and out..

 

[WDoherty]

it is a dellema, although the trade +1000 cash is a great deal. His car is actually worth twice of what your's is and in a way you'd be recouping value you never could have with your modded car. It seems you have made up your mind though. Just one thought though, lextreme tc $175, tex headers $600 + shipping, install, exhuast $300?, tt auto lsd?, srt intake/ecu $449 and you have a car that will run a mid 13 1/4 and dyno i'm guessing close to 270rwhp all n/a. Now that would be cool, that's as fast as an ls1 camaro, 2005 mustang gt, is350, etc. Then there's that nos stuff your so found of.

 

[jibbby]

WD your points are valid....Your forgeting about a few more expenses like suspension (coilovers) $1000, rims and tires $2000, ECU piggy back and tune ($500), tint, torque converter install ($300) Supra LSD ($500), etc.....

260-270rwhp N/A would be sweet for sure in the 98, but again I would want to boost down the road for sure and that presents a tuning problem from my reads, plus all the these 98 mod expenses is the real killer....

I just got to thinking if I drop a good set of cams and port the heads on my 92 SC4 I will be right there with the N/A rwhp numbers as the mod'd 98... Cams and port job $1000-$1500.... Much more cost effective then all the mod's that will go into the 98, plus I just built up my tranny two months ago for a couple of grand...

My 92 is ripe for boost...

The only decision I need to make now is -

1) Go ahead and single turbo and forget about the cams and heads on my 92 SC...
2) Or port the heads and install the aggresive cams to increase N/A power and stick with my current NOS system for the occasional races....

 

[Lextreme II]

Jibbby,

I can do this for you. Put in a 4.3L lower and use 1uzfe (VVTi) uppers. Now you automatically gain .3 liters for the price of 4.0. Second thing I can do is stroke the crank to bring it up to 4.6L. Now that is something to consider.

 

[jibbby]

Lex we need to hook up one of these days... Besides the above topics, I would love to see how your LS400 runs now, remember, I road in it when it was having those head gasket problems..

I would still need to swap in the 4.3l lower block and stroke the crank then install VVTi uppers...Hmmmm? I would probably need a stand alone ECU to control and tune that beast right?...Sounds expensive...Not as easy as it sounds there Davey....Woundering what N/A power a setup like that would produce?

Interesting suggestion though...