fadedsc300

Hey there, questions regarding Whiteline's Front and Rear Sway Bar upgrade on the Lexus SC300 from Stock Front and Rear Sway Bars.

Pros and Cons?

Differences in 22mm and 30mm? Advantages and disadvantages?

I don't know much yet regarding Sway Bars but I would like to know.

Slowly upgrading my Lexus SC300.

Thanks in advance.

Sunny_Tk

I am literally doing the install right now, along with Power by MAX coilover install. I will let you know tomorrow how it goes. The kit I got was btk008 which includes BTF67Z(front) & BTR79Z(rear) sway bars which is supposed to be soarer/SC specific. Their site lists a different part number for the mkiv supra for the rear (BTR68Z).

FSUsucks1

iTrader: (5)

I've had them on my car for a while now and I felt the difference from day one....I love them. I have the front and rear set , 30mm up front.

KahnBB6

iTrader: (5)

Whiteline is a well known and well regarded suspension parts company.

Previously the two upgrades available for SC's were the Daizen swaybars or converting to a Supra TT style rear swaybar with matching subframe mounts.

I can comment that the Supra TT bar upgrade is a night and day difference, but that's only 22mm (93-96 TT rear bar) with different anchor points than the OEM SC anchor locations.

30mm sounds very aggressive. I can't recall offhand what Daizen's rear swaybar measured at... perhaps 25mm? OP, does Whiteline offer any other diameters for the SC?

Whichever rear swaybar upgrade you use, be aware that wider rear tires tend to help and the factory SC alignment settings used with a swaybar upgrade tend to make these cars more tail happy. I have had better results using Supra Turbo "Lance" alignment settings to maximize a balance between traction, handling and tire wear once I put on a more aggressive rear sway bar.

The front swaybar isn't as much of a dramatic change but I have heard people say they have and haven't noticed a difference with an upgraded front Supra TT or aftermarket swaybar. Depends on the setup of the vehicle. Rule of thumb is that generally a bigger front bar promotes more understeer to counteract the rear.

Supposedly the SC300 has a hollow front swaybar and Supra TT's used solid front bars with the only visual difference being slightly different bending to accommodate intercooler piping. Based on this, I would assume the same logic applies to aftermarket solid front swaybar upgrades for the SC.

I've been running the factory SC300 front bar with the Supra TT 22mm rear bar (again anchor points change to the rear subframe mounts for this; the SC factory location bars anchor to the trunk floor) and a Lance alignment for a few years now. Very good combination for an aggressive street car. The same hardware with a stock SC alignment settings was, as mentioned, much more tail happy. This is amplified with an LSD.

30mm just seems on the very aggressive side for street cars in my opinion. Again, Whiteline is very reputable. I'd just check to see what type of driving application they are recommending this particular setup for, OP.

t2d2

iTrader: (8)

It doesn't have to be the TT version. I have the 2mm smaller NA rear bar and it's a fairly noticeable upgrade from the stock SC bar. I went with that because the package deal with subframe mounts and front LCAs was too good to pass up, and I could always upgrade to a bigger bar later with the hard-to-find mounts taken care of. I'm thinking it's plenty stiff as is, though.

Isn't it the other way around? I thought the TT front bar is quite a bit lighter due to being hollow.

BTW, are we sure the OP's 30mm rear bar spec is correct (or interpreted correctly)? That sounds like a mixed up figure for the stock front bar.

KahnBB6

iTrader: (5)

^^ t2d2, you made a good purchase with a package deal like that! Yes, with the anchor points being changed even the 20mm NA bar will make a difference. All NA's from 93-98 and 97-98 TT's should have 20mm rear bars. Only 93-96 TT's had the 22mm rear swaybars.

The front bar, to my knowledge, is solid for TT's. Not sure about NA's. It's almost the same save a bend in the middle allowing for IC piping clearance. Diameters should be identical between the SC and all MKIVs. The idea, I think, was to have slightly more understeer dialed in with a stock TT for better predictability with at-the-limit driving since the rear will already be very easy to kick out.

With a stock SC... I think the aim was to dial out nearly any possibility of oversteer at all (from the factory). I'd be curious to learn if the Soarer 1JZ swaybars are any different or not.

I just checked Whiteline's website listing for the SC/Soarer:

http://www.whiteline.com.au/do_segue...=1%2F1990-2000

It looks like what they have is a 30mm front swaybar and a 22mm rear swaybar which retains the factory SC/Soarer anchor points. The rear bar makes more sense, but probably won't be as aggressive as a Daizen rear swaybar. Not sure how this compares to the TT sway setup but I don't believe it's quite as aggressive either.

The front swaybar is what strikes me as interesting. I have heard of a very big front bar being used on heavily modified TT's. I'm not sure why such an extreme diameter would be desired. Maybe for track road racing applications with very high horsepower where the additional understeer lends more predictability at the limit.

Compared to a stock SC, however, most of us actually want slightly more oversteer versus the hovercraft-like stock tune. Again, with the stock SC alignment settings just going with coilovers and a rear swaybar upgrade makes a case for switching to Supra MKIV NA, TT or "Lance" alignment settings to smooth out the handling balance.

Blkexcoupe

iTrader: (8)

I'm curious, are you basing the comparison for stiffness to daizen based off of the thickness of the bars?

I was lucky enough to get a whiteline supra rear sway bar for free from another member. When I got the bar I was really surprised by how thin it was (20 mm) and also by how heavy it was, but it looks like a great piece. I still need to get the supra subframe mounts (which are more expensive than I was expecting) before I can install and write a review. I'm kind of worried that only upgrading the rear bar without a matching front will throw off the balance of my car too much.

t2d2

iTrader: (8)

You know the subframe mounts are hard to find when someone says it was a good deal without even knowing the price.

https://www.clublexus.com/forums/sus...-bar-here.html

First post is at least part of what I was remembering, with the SC front bar being 27% heavier than the Supra one. But then, you knew that. That would imply both are solid, both are hollow, or the Supra is hollow and the SC is solid. I think I also saw talk of the Supra bar being hollow with regards to aftermarket upgrade options, but I can't swear to that.

That's the main criticism I've read of it. It's got good stiffness and adjustability, but it needlessly adds weight to get there by going with a smaller diameter for no good reason.

KahnBB6

iTrader: (5)

Hah! Well, you can still buy them from Toyota, I think, but nothing wrong with finding them used. The mounts themselves never go bad other than (after decades) the rubber bushings needing replacing... and there are aftermarket polyurethane bushing solutions for that, too. Also, I can't confirm this but I think I've seen an aftermarket subframe mount kit within the last couple of years. None of this is exactly cheap but I don't think it's hard to find these mounts if you are dead set on putting a set in your car

t2d2, I'm sure you're right... I can't refute the 27% heavier figure with any contrary evidence (the MKIV program did begin from the baseline of the SC/Soarer after all and weight savings ideas were applied *everywhere* during R&D), but what I have read before is that the SC front bar, despite it possibly being heavier than the MKIV front bar, is supposed to be the one that's hollow inside.

I read this PDF before converting my car:

https://www.clublexus.com/forums/att...t-to-sc300.pdf

I do think there is something to converting to rear AND front TT swaybars (or a matched set from an aftermarket company) but I've found it isn't explicitly necessary to change the front one as well. Nonetheless I will be doing so soon, mostly for MKIV/Soarer SMIC piping clearance... if that information does indeed hold water as well.

Interesting that they'd go with a smaller diameter than stock despite the extra weight from solid core swaybars. I do think that, solid vs hollow does make a difference despite any extra weight but unless the SC300 rear swaybar is larger in diameter than 20mm that is an odd choice.

Though they are notoriously hard to get your order from, I would compare this to Daizen's rear swaybar, OP. Not sure about their front swaybar.

t2d2

iTrader: (8)

https://www.clublexus.com/forums/att...t-to-sc300.pdf

I also read, and saved a copy of, that PDF before my install, but forgot it referred to the SC as the hollow bar.

"The Supra TT has a suspension between Sport and Race. The SC front sway bar is hollowed out to provide more flex. The bends in the bar are less sharp than the Supra’s attributing to the looseness."

I can't help but think the confusion is a matter of a bad assumption on the part of the PDF's author. Did he or she dissect both bars to see a hollow cross-section? It seems to be based on the extra flex of the SC bar, but isn't something like 95% of resistance to twisting a matter of surface area? The solid bars don't add much in that respect. That brings us to the second part about the SC's bends being less sharp (and looping about more) as the more likely source of extra flex, same as with the rear bar.

Agreed. I would have picked up the front Supra bar as part of the bundle if not for the comments that it's an extremely tight fit with the oil filter on SC400s.

scENFORCER

Dont forget Titan sway bars. I think they were made for the Supra application, but I had them on my old SC. Night and day difference with/without them. Made the SC feel like a gokart (combined with my coilovers) on the highway