Vortech on a tired 1UZ-FE

Thermactor

Member
Well, I lost an auction by $.50 to get a 3.33" 6-rib pulley for $20.50, so that is out. It might be for the best, though - Arnout's story of a UCF20 spitting out its rods at 7PSI scared the shit out of me. These rods are a disgrace to the Toyota name. The 7M rods can handle 700hp, with two fewer cylinders. Arrgh..

The car: 1996 LS400 with high miles but runs fine otherwise. No oil consumption, fires on all seven cylinders. (we have seven, right?)
The blower: Vortech V2 SC-trim
What I'm looking for: Better midrange response and power. Right now it's downright pathetic.

I have the car, the blower, and the fish bracket. I have a 12:1 FMU in the mail. To start with, I don't want to run an intercooler if I don't have to. I won't do any fuel or timing adjustment outside of installing the Vortech FMU on the return of the fuel rail. Fuel itself will be 93 octane pump gas. Car is a daily driver.

As it is, I'm sort of on the fence between these two pulleys:
http://www.summitracing.com/parts/VOR-2A036-361/ - Vortech 3.60"
http://www.summitracing.com/parts/VOR-2A036-500/ - Vortech 5"
The 3.60" pulley will spin the blower up to 34,100RPM at redline. I believe that in our application, the 3.60" returns 6-8psi of boost.
The 5" pulley will spin the blower up to 24,000RPM at redline. I think that it should equate to, oh, five pounds of boost at redline. Extremely conservative, indeed. The added benefits of the 5" belt would be greatly reduced belt slippage and less parasitic drag on the motor (of course, and less power). One other benefit I can think of is less pressure on me to get a badass bypass valve. I think a Bosch 110 or 114 would probably do me just fine.

I don't want to overhaul or replace the motor. I don't want to spend money on engine management or any tuning at all, at this point. I'm not about to rip out the stock fuel pump. I can do all of those things, but I have no desire to, because they lead one down a slippery slope of modifications and repairs that quickly eclipse 5-figures.
I am just looking at this as a way to get my power up to LS430 levels, and retain stock reliability and economy. My driving style is conservative. In the past I had an MkIII Toyota Supra N/A that I turbocharged, and kept the stock motor. It was a blast even without going into boost or speeding, and I loved the on-highway power surge I'd get with a gentle tip into the throttle. I want something similar for my LS400.

So I'd like your advice. Which pulley do you think would fit my needs better? 2.87"? 3.33"? 3.6"?

.. 5"?

Thanks :)
 
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kc95sc400

New Member
Here's where I bought my pulley. http://www.superchargerupgrades.com/

I have the 2.25 if I remember right. I have the 7 rib pulley that I was using laying around somewhere, I think it was a 2.4.

Smaller than you want I know but the above sight was allot of options.

I also have one of these - http://www.928m.com/parts/boostlimitervalve.php - sort of. The one pictured in the link appears to be different / updated. In theory, you could run a small pulley to get boost quicker but blow off the boost you don't want.

Also, I don't run a bypass / BOV valve, haven't had any issues. And, if your belt is slipping you either don't have it aligned correctly (I struggled with this allot, ok now) or it's not tight enough (I have a trick if your interested to know).



KC
 
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Thermactor

Member
KC, thanks for the post. I will probably move to a small pulley and a boost limiter valve after initial setup is complete and I have time and money to tinker with cool add-ons like that. In the meantime, I'm still looking for a cheap pulley. It looks like we have a fairly small crank pulley (vs. mustang guys with a 6.87" blower-end crank pulley) so that means that a 3.6" blower pulley is only good for maybe 2.5-3psi, which would be perfect for me. My usual RPM range is between 1500-2500, and if the power is right I don't ever want to go to redline or even past 4000rpm, just like on my old NA-T Supra.
 

stevechumo

Active Member
7 psi with a FMU and a high pressure high flow 255 lph fuel pump is good enough. I just found out the Supra MKIV TT is a better choice than Walbro because it has 300 lph and much higher pressure tolerance.
 

kc95sc400

New Member
Does anybody know if an 8 rib pulley can be used with a 6 rib belt, with no ill consequences?
As long as you align the belt for 6 of the ribs AND the grooves in the pulley are pretty deep, you should be fine. I ran mine with the 7-rib pulley without issue for awhile.

Thermactor said:
Would the Supra pump make the car run excessively rich during off-boost driving?
I wouldn't think so, not more than the ECU can compensate for anyway.

KC
 

stevechumo

Active Member
Would the Supra pump make the car run excessively rich during off-boost driving?
The Supra pump with more capacity won't make your car run any richer. Its bigger capacity will allow it to sustain higher pressure and to pump more fuel when needed. It's safe to have it.
 

Thermactor

Member
I have two pulleys now - a 2.4" and a 3.75". I will start off with the 3.75" for initial running purposes, and if I find the power to be inadequate I can switch to the 2.4" and a boost limiter valve.

Now I'm at a crossroads: I can get a JDM 1st-generation (I'm assuming) 1UZ-FE for $575 picked up. This motor will have low miles, of course - and I am at a stage where I have the time to install it. I don't know about the future. An early, relatively fresh 1UZ-FE should be able to take a lot more boost without pooping the bed. Should I go for it or should I just kill the 260,000 mile '96 original first?

As far as mounting up the blower to the fish bracket, I found that the V-2 blower uses 3/8"-16 bolts. It looks like 5" is the right size but it might also be 4" - I will have to actually mock it up on the car to be sure, unless someone's done that part of R&D and is willing to share! Unfortunately the temperatures are consistently around 15 degrees and snowy so it's impossible for me to do anything to the car at the moment.
 
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kc95sc400

New Member
If you have the money and space to keep it, I would say go ahead and get the motor but keep it just in case.

If your current one does ok, build the spare up as you have the time / money. Then put it in and shoot for 20-30 psi!:D

KC
 

Thermactor

Member
If you have the money and space to keep it, I would say go ahead and get the motor but keep it just in case.

If your current one does ok, build the spare up as you have the time / money. Then put it in and shoot for 20-30 psi!:D

KC
Thanks dude. For now I'm going to just run the stock motor. The additional power I need is indeed quite little - comparable to the gain you'd see doing a 5-speed swap and a proper intake and exhaust,
and hyper ground wires,
and type-R stickers
and a junction produce headrest :rolleyes::D

Still waiting on better weather, to clear the docket of other cars that need immediate care, and the current rash of exams to get down and dirty with it.
 

StockSC300

New Member
I'm running a Walbro 255Lph pump on my 1UZFE powered 240sx and it runs pig rich all day long at idle. it reads out 13.5 AFR and when cruising its right at 14.7, but at a stop light or whatnot my eyes burn due to the excess unburnt gas being expelled from the car!!

the factory fuel pump has a staged system I believe, that delivers a certain low voltage to it at idle and then amplifies that voltage a lot higher during normal driving.... maybe.
 

stevechumo

Active Member
I'm running a Walbro 255Lph pump on my 1UZFE powered 240sx and it runs pig rich all day long at idle. it reads out 13.5 AFR and when cruising its right at 14.7, but at a stop light or whatnot my eyes burn due to the excess unburnt gas being expelled from the car!!

the factory fuel pump has a staged system I believe, that delivers a certain low voltage to it at idle and then amplifies that voltage a lot higher during normal driving.... maybe.
The fuel is a return system, so even if it pumps more than a regular pump, the unused fuel will be returned to it. I'd suspect the fuel injectors or pressure regulator, or perhaps swap in a piggyback ECU and tune the injectors.
 

spf_lexus

New Member
It's really hard to ride the edge of safety on an unopened 95+ motor. If you can swap the rods w/ early ones you wont have any nightmares. As far as reaching the 300hp levels of the ls430 I would look at intake + headers + exhaust. Those should turn your 260hp into 285, and if you can get a piggyback to tune it I could see 300crank hp no prob.


The weak rods aren't really a fault of Toyota (to us modders they are!) but an engineering decision to increase power and mpg. 95+ motors gained that 10hp over the early uz from lighter/skinnier rods with a light boost in compression.



As far as pullies go, I am running a 3.4" pulley at 7psi on a procharger. Every .1" increase nets me 1psi of boost. That 2.4" should put out 17psi!!! I don't know if the vortech varies at all.
 
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Thermactor

Member
I've run into a huge problem. The fish bracket won't work on my car. The bottom edge of it is too low. Even with trimming, there are A/C lines in the way of the mounting bolts and blower. I'm not going to remove or reroute the A/C lines, either. I guess this is a stopping point for me. Anyone want to buy a blower?
 

spf_lexus

New Member
hey Therm,

Do you have the second version of the FISH bracket? The 1st one I used smacked the A/C lines until the second version was made. Now I have 2" clearance above those lines. The frame rail shouldn't be any different between our different years.
 
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