Paul Booth

Interestingly, I was looking at the Fensport site (TRD) and they're starting to do a full set of Polyurethane bushes for the JZA80. They've got both Koni and KYB shocks, springs, oh the works, and at what seems on the face of it, quite reasonable prices. Guess what's just gone on to *my* shopping list? *pardon*, *what*, you'll have to speak up, the tyre noise has made me deaf

Welcome.

Yes they are hollow, and the whiteline ones are SOLID S'cuse me Rich but there was a point higher up regarding what comes with the Whiteline kit I was expecting you to answer. Gavin, the main reason rubber bushes are fitted to cars is to try to reduce the noise transmitted from the road, engine, etc. but you don't get something for nothing. The ideal connection is solid everything but that will rattle your teeth out, so you compromise. The moment you fit a rubber joint in the suspension you get changes in geometry every time something moves, i.e., over bumps, when braking and just general flexing. Therefore the more solid you make your rubber bits, the better it performs and the more noise is transmitted to the bodywork. I was interested in the stock+27%, the +50% seems ridiculously stiff for road use and matched with a +27% front, it's going off on the first bend; Yeuch.

OK, that's x 4 bushes(?) but nevertheless, bushes are one of the most important parts of a suspension tuning, in the extreme the bushes get replaced by UJ's and swivels to remove *all* non-specific movement. I agree, they are charging that figure *because they can* but you won't get *all* the benefit of the anti-roll bar without matching anti-roll bar bushes. If there's an alternative bush supplier that can match the over-sized bar with harder bushes then great, however........ Once it comes to wishbones and trailing link suspension with performance bushes, it can get *really* silly. We used to buy the performance bushes seperately, reinforce the metal suspension parts to the same spec and then have a local engineering company press-fit the bushes for us. Used to save £100s. In this case, I can't see a comfortable alternative. Don't wish to insult, and please forgive me if I patronise, even slightly, but you know the road noise is going to increase on harder bushes?

That's probably the best value for money for a handling performance upgrade I've seen to date. Sign me up What do you mean by expensive?

According to MVP Motorsports there is a TRD antiroll bar kit which is both front and rear at 27% over stock and a special which is a rear only at 50% + over stock. I have been considering the TRD 27% kit as I am not unhappy with the softer stock springs and the ride height (I'm not a lover of lowered cars) but would like to reduce body roll on hard cornering. I would expect that TRD took time to get this kit right and the quality should be unquestionable. I too am quite pleased with the handling, no tramp, I don't have any dive problems under heavy breaking and I don't suffer wallow. I think this is down to my bushes still being fairly tight. I'd like to try the TRD anti-roll bars to see if I can tune out some of the oversteer. I don't want to go to the astronomic expense of stiffer springs/shockers as that means having to also uprate all the bushes too for it to have any meaning, and I have yet to here/see any mention of a set of competition/fast road bushes. If you do find out the price and it's not ridiculous, could I ask you to let me know please? BTW, make sure they come with suitably uprated bushes, or there is a part number for some.

Neutral. Thought it was my imagination at first but I've done it a few times now. I'm not saying it's supposed to or that I didn't confuse the poor thing, just that it does. Maybe hence the grating noise when trying to put it in gear.

I read that as being on the front at first reading but I guess you mean all round for £1500. Does anyone know (e.g. Rich) what the Whiteline set comes with and for how much?

I think that big wing on the back end has gone to your head a bit. "Come in red leader, bandits on your 6 o'clock" :biggrin:

Given the speed of the up-change, I just can't see a throttle flap closing cause a fast enough response and it's probably coupled with retarding the timing and shutting down the injectors too. Ergo, if it continues to do everything else, it probably doesn't really need the butterfly. Pete Betts expressed the opinion that the Supra has a gear selector rather than a belt and clutch arrangement and why it's able to handle so much grunt. I was a bit skeptical about that until I grated the gears this morning. I'd been refitting the dash and had the selector in neutral. I started the engine and moved the selector towards reverse; it grated. Made me think about Pete's idea more seriously. That being the case, any errors changing gears would be very audible and I'm therefore probably going to swap out the butterfly when I get chance this week.

But you should know by now Phil, if it's there for a reason, I like to know why and what the effects are before I start attacking it. I've asked Pete if he's ever scoped the ECU during gear changes to see what the ECU is doing during an up change. I'd actually like to know if the ECU *really* closes the throttle flap during up changes or whether it just thinks about it.

One of the modifications to improve intake air flow is to remove the secondary throttle butterfly. On a manual car this is a *very* worthwhile mod as the only function it's performing there is the totally useless stock traction control. On an auto model, there seems to be some ambiguity in the functional spec and the TRC is *supposedly* used to reduce torque during *up* gear changes by momentarily closing the secondary throttle. Although this is what is stated in the 'Good Book', it has to determined whether it actually does anything useful. However, the possibility that it *may* be removing stress from the gearbox during up changes means I have hesitated to fit the HKS secondary throttle removal kit. I've just finished off locating the RLTC and wiring in Pete's FCD and was wondering if that's my last assault on the passenger footwell. As it does in your dotage, my mind wandered to the 'full-throttle' clutch switch gear-change, whereby the RLTC *reduces torque during gear changes*. AHA! If I wired the secondary throttle actuator circuit such that it asserted a signal to the clutch switch sensor input, the RLTC would rev-limit/reduce when the TRC was trying to reduce torque *only* during up changes. I could therefore remove the secondary throttle in its entirety as being guaranteed redundant. Just one question/thought. What is the *effective* difference between closing a throttle butterfly for a fraction of a second and momentarily shutting off the injectors; bearing in mind the latter is exactly what the clutch switch does? I can't see a major problem and if no one spots a 'gotcha' I'm gonna put it on my list.

Well I'm glad I wasn't the first to raise this. I keep hearing stiffer spring or stiffer shock or stiffer spring and stiffer shock and I only remember a single post where the anti-roll bars were mentioned, and I think that was part of a group purchase enquiry. It's my understanding that the springs and shock absorbers are tuned to keep the wheels in contact with the tarmac for the maximum duration and that the anti-roll bars were the most significant part of the suspension while cornering (ignoring the joints and body-shell for the moment). Therefore, if you're not getting tramp and you're looking for better cornering, surely the first things on the suspension to tune are the anti-roll bars. I think most people seem to forget that the handling of the car is the sum of the tyres, wheels, suspension joint stiffness (ideally being solid and not rubber), spring+shock+roll-bar, body-shell stiffness. Change one item and you lose what should be a 'designed-in' flat response, unless you tune it back to flat by changes right across the board.

Yes, it's all a bit elementary though isn't it. What it doesn't cover, at least I dind't see it, skimming through, is the extra forces placed on the brakes on fitting larger diameter wheels and/or wider tyres. I won't make this a mammoth post by going into the physics and anyway, I don't happen to like standing up on my pedal every time I need to stop in a hurry. I'm at an age where I want shopping trolleys to have PPS and vacuum assisted brakes. The one point I picked up worth noting was that the recovery time goes down. Either way, I understand the issues, what my purpose is and what the overall effect will be.

Worrying, isn't it :biggrin:

Martin, are you using an electronic boost gauge or mechanical?

Well spotted that man. I noticed that too but it makes me feel like an old fart (being one and feeling one are two different things) making that point every time someone asks about improvements. We should have a page with all the options on and the BIG brakes options should be at the top of the list. See, now you've got me on that blasted soapbox again. NURSE!!, my medication if you please.........

Yeah, but imagine a Supra that will clock 160MPH in reverse gear and pick up women even when I'm not in it. Just gotta deal with the wheels' electrics failing every 1,000 miles and bits of the dashboard dropping off after every pot hole.

If your posting is for me, you don't read all the threads, do you Simon? I've had my BIG brakes sitting on my garage floor in a BIG crate waiting for some custom made flexible hoses (to my spec.) and the right wheels, for about 3 months. The de-cat pipes were fitted out of synch because they came along at the right price and the right time. They're fitted with the stock exhaust to limit the number of issues I have to deal with at the same time.

Murky bucket moan sewer. Wheelmania tell me they're waiting for the confirmation from the factory in Italy. Should I be worried about Italian made wheels? ?

Thanks, I have a spare motor too, so that's not an issue. It's not *that* far to Dartford from Kingswood. I know this as I forgot to come off the M25 at J8 and carried on round, 2 weeks ago. Double DOH! I work in Kingswood....who are you working at? I think we did this conversation last time round Gavin; the BBC have a converted mansion in Kingswood which is the R&D centre. As it's my job to identify technology which the BBC might turn into money, I get to travel there as and when I feel the need.

Thanks, I have a spare motor too, so that's not an issue. It's not *that* far to Dartford from Kingswood. I know this as I forgot to come off the M25 at J8 and carried on round, 2 weeks ago. Double DOH!

Well, if no one else has volunteered to help by Friday, I will be finishing early then and we could arrange to meet up. I'd still try Findapart in the meantime too. Abbey Toyota in Redhill are ace at producing J-spec parts too, give them a ring and price up a nice shiny new one.

Did you try Bracknell Tyres? I got 265x35x18 for £149 each. Micheldever were way more expensive (have a look at the thread for exact prices). BTW, something to keep your eyes open for. Many of these smaller operations/chains have links into tyre clearing houses. You can get a nonsense bargain on some tyres if the manufacturer is dumping stock. No I didn't try them, but I will next time. I'm happy that I got a good price all in all and Micheldever are well organised bunch I was in and out in less than half an hour. regards.................. Obviously I can't speak for everyone at Bracknell tyres but the guy who did mine was so careful with my Allies, you'd have though they were his. OK, I was watching him and he knew that, but I've been to other places that didn't give a damn who was watching. They too had me in and out in well under 30 minutes.

More boost still? I'm not sure if I need it...... yet. Yes I'm running the stock exhaust. I looked at it and it seems to be adequate until I get my UK brakes fitted (damn, meant to go in to Halfords and reconsider those Mag OZ Superleggera). Paul......There is a MKIV round at Leon's with 18" OZ Superleggera's fitted. They look quite good on a silver car and in my opinion would look even better on a red one. You wil be please to note that this car had a set of AP brakes nestling under the wheels. I think Branners will confirm that AP's are larger than the UK spec brakes which would suggest you may well be okay with that choice of wheel. regards........... AP brakes are way bigger than UKL spec. I'm feeling more optimistic by the day. Wheelmania in Birmingham will sell me a set of Superleggeras (10" & 8" or 9") for £1100 and they talked as if they've already fitted them to a UK spec Supra as they seemed to know all about the issues. I've told them they can have my pennies when I get a fax saying they've checked and confirmed it. Halfords want £1400+ for the same set and Justin says they don't make 10". Concerned but not worrying too much just yet.