OnlinBirch

Right, I'm the guy who constantly posts about squeezing a little extra power from my stock 95 LS400. I'm just curious if some aftermarket cams could help in that without killing my motor and sacrificing daily driving.
I'm mainly worried because of the weaker internals compared to the 90 - 94 models.

I'll end up doing an aftermarket ECU before I go for some cams, I'm mainly just curious if it's at all viable for the 95 Models updated engine internals.

RA40

iTrader: (6)

The aftermarket stateside is not strong for performance goodies or read that as zero for off the shelf bolt up and go parts. Would require custom work for nearly every step and more so for the age now. May read through Lextreme to see what others have done.

OnlinBirch

I know Stateside the aftermarkets weak as ****, but I know there are aftermarket cams made specifically for the 1UZ (Kelford makes some). I'm just curious is doing a cam setup would even work on my 95 Motor.

YODAONE

Purchasing a 1998-2000 LS400 (VVTi) presents a less costly option.

You can take that and plug-and-play a 3UZ-FE engine...

400fanboy

How is the difference between the 2UZ and 3UZ? You get a bit more torque and a couple horsepower, but does that really change the car much?

YODAONE

The 1UZ-FE and 3UZ-FE installs into LS400 without fabricating motor mount brackets, while 2UZ-FE requires fabrication (Anyone who has replaced engine mounts, the fit is already tight)

The 2UZ-FE is iron block vs Aluminum 1UZ-FE and 3UZ-FE. so extra weight.

Lextreme composed comprehensive comparison write up on differences of three blocks

dwoods801

The cams can give you some added power at high rs but you’ll be giving up the low end torque that is very useful in most daily drivers. Any generation 1UZ motor is over built by industry standards. Even though they were ridiculously heavy duty duty the first few years, even the thinnest rods of the later years are still excellent components. And a set of cams isn’t going to put additional stress on the motor unless we are talking about making the modifications needed to increase the redline. If you were to increase the compression ratio then you would need to worry atart worrying about longevity.
Just curious, if u want to add some power without shortening the life of anything and for a reasonable price, check out this kit for a supercharger

YODAONE

Keep in mind a 4.0 liters is 240 cubic inches engine propelling a heavy sedan...four valves per cylinder really sing at higher RPM's, but are not as proficient producing torque at lower RPM's..so cams, depending on use, may not be optimal.
One way to pick up power and improve efficiency across the power curve is to extrude hone your intake manifold to remove casting seams/flash and mirror smooth inside the intake runners.
I did so on 1999 manifold with excellent results.

A post on topic with dyno results:

https://www.clublexus.com/forums/ls-...rude-hone.html

One way to work this is to acquire a spare intake from a donor vehicle, clean it and send it to extrude hone.

I does not appear your intake will require any special fixturing (block off plate) as was necessary on the 1999 ACIS tuned manifold..

400fanboy

Wow those results from more or less better intake runners is way more than I expected. Smoother cooler laminar flow with more ignition timing. Curious on just how much timing was able to be gained.

tl;dr +20-25 ho\tq, significant gains under the curve in the midrange.

In my limited knowledge I know LS motors respond really well to breathing mods (hence why LSx heads are so popular, as are intake\exhaust). I didn't read the full thread and your comments - but do you have any thoughts as to why this process wasn't done from the factory and this much performance was more or less left on the table? I would imagine it's a cost\tooling issue?

dwoods801

The cast aluminum intake manifolds that were standard across the 1UZ 3UZ lifetime are produced fairly quickly and affordably in high numbers. They need to be fairly thick to ensure they are very strong. The cost to have them hand ground to the optimal flow would increase the cost substantially. Ferrari uses individually sand casting techniques on some engine components like the intake on the F430. They are able to maximize flow but it takes several hours to produce just 1 manifold. GM opted to use a composite intake on the LS1 and it improved the flow and lowered cost but they created other issues.

YODAONE

Extrude honing is not new, but not on late 20th century radar for mass produced Aluminum intake manifolds.
While pressurized semi-viscous fluid with embedded abrasives does an excellent job of smoothing intake runners to uniform flow,
it requires fixturing and machine time to achieve results...which if scaled production, would probably add $200 - $300 to cost of production automobile...
Contemporary intake manifolds are molded in plastic which offers considerable weight savings, more uniform flow and smoother intake runners with decreased heat soak...BUT...as with all plastics, they're going to warp, creep, distort, separate and, or crack with age.
The 1998-2000 LS400 and 2001 -2006 LS430 Aluminum intake manifolds are HEAVY.
You can literally throw out your back attempting unaided extraction.

If TRD offered a high performance resin-filled high performance lightweight plastic alternative, would be popular

A little off topic to OP's inquiry on camshafts, but am presenting an interim.

dwoods801

I understand, my point wasn’t that they couldn’t do it, just that manufactures are focused on creative solutions to improve things. There use to be an expression that went something like, there isn’t an employee in the company who would be off limits if their death would decrease the per vehicle assembly price by a nickel per car and family members would be at risk for a dime per car. Or something like that. But that’s fine not everyone would notice if u removed half their spark plugs and replaced them tootsie pops.
But this is the exact type modification I Love, the majority of the investment would be paid with my time and not cash, and the results would be a noticeable increase in performance.
Drag racers use to exploit any advantage they could find. And never let anyone else know the secrets that helped the most. There is no shortage of improvements that can be gained with a little knowledge and time to exploit them. Very few people balance or blueprint an engine after having it rebuilt. The heads can be ported to perfectly watch the intake and exhaust manifolds. Compression can be increased if you have the mating surface of your heads milled down and reduce the size of the combustion chambers. And increased compression is critical when trying to build a really powerful engine. And it’s one of the easiest things to under stand and recognize potential increases. Your potential to pre-detonation if you don’t increase the octane in your fuel. This was how horsepower was increased before the boost revolution arrived a few years ago.

timmy0tool

iTrader: (7)

The 2UZ is 4.7L with a iron block as you stated (mainly for SUVs/trucks) so fitting it into a sedan will be a tight squeeze indeed! i know the 4.3L 3UZ is a decent fit from your experience.

speaking of intake manifolds, the newer 2UZs with VVTi's intake manifold changed from metal to plastic. i wonder if the manifold will work on the 1UZ/3UZ?!

OnlinBirch

In the past I've actually considered doing an ITB setup for the Intake manifold. Do you think this would be a good idea at some point if I don't run a supercharger?

YODAONE

Have looked at this..

Attempted to receive height dimensions on plastic 2UZ-FE manifold from Toyota...but without success. (It appears taller...)

ACIS?? (Variable intake runner length)

Also..unsure whether they incorporated air mix paths...

Anyone know?