Roman

You might have the OSNAP turned on (true story) I can spend a night with you. Oh, I could teach you some CAD stz too, at cost of Cider

Haha, used to work for a structural steel company with a big BIG water jet cutter, more than once it it went smashing into a concrete wall because of a small spec of whatever on the drawing, 6 meters over to the left that it felt it needed to cut out. (Turns out it was a bug in the program, not a random piece in the model)

Installing tomorrow... downloading... downloading... 11 hours till download complete

Hey cheers for the input! Yeah thats a really good point about turbo engines, didnt think of that. And yep, with non roadcar transmissions where you can smash through the gears almost instantly, there's more of an advantage to chopping through a lot of gears up to a certain speed. A lot of aftermarket gearboxes have the 5th or 6th gear as 1:1 as well, so you've got a really tall 1st gear, then a crapload of them within a narrowish speed range. In which case a really high diff ratio might not suit anyway.

Just a few thoughts down on a page about final drive ratios, and what happens when you change it. The final drive ratio turns rotations of your driveshaft, into rotations of the wheels. It also turns power sent to the crankshaft, into power at the wheels obviously. As a general rule, depending on final drive ratio, for every 3-5 rotations of the driveshaft, the wheels will turn once. Which isnt too complicated, but what are the advantages of changing your final drive ratio? Some people say that changing to a higher ratio (say 3.5:1 to 4:1) increases the torque at the wheels. Although this is kinda true, it means that you are creating more torque, at less speed, which is the trade off. If you are going 100kph, you are going to have less torque available than 50kph, because it has to share the available torque between say 200 turns of the wheel rather than 100. This is one thing that the horsepower formula is for, it lets us figure out how much torque you can actually use at a particular speed. So forgetting gearboxes, final drive ratios, and all the rest of it for now. Lets say that we had a wheel, which has 200hp, 150hp, and 100hp available to spin it. How much torque is available, depends on the wheel speed. As per below, based on Torque = (5252*Horsepower) / RPM, and a 205/50/15 tire As you can see, when the wheel speed increases, you lose torque. Waah. Obviously no motor has 200hp through out the whole speed range, as when the motor goes through its own RPM range it picks up or loses power. Also, obviously the car changes gear as the speed increases. So the amount of torque actually available at the wheels looks more like a sawtooth pattern as we go through each gear: Some people say that changing the final drive ratio, increases the amount of torque available at the wheels. What it actually does though, is it changes the speed at which each of your gears work... it moves the sawtooth pattern up or down the graph. So although at some points on the graph you DO gain torque, you are also moving the dips as well. As per the blue line below: It's impossible to have more torque available at a given speed, without more horsepower. As you can see comparing the blue line to the black one, every time the blue line is higher than the black, more torque is available at that speed. However you also have LESS torque available, at other speeds when the blue line is lower than the black one. So, when IS it useful to change final drive ratio? In my opinion the biggest reason is to change the speed at which each gear in your car starts to work. If your car came with a motor which peaked out at 5000rpm, and now you've got a motor that goes to 9000rpm, 1st gear might have previously gone to 50kph and now goes to 90kph. So you can change the final drive ratio, so you are getting into the powerful part of the powerband earlier in the speed range again... So first gear might top out at 50kph still, but now at 9000rpm instead of 5000. Also, it can be useful to change the final drive ratio to suit particular corners of a track, for example if your car was getting unsettled because you had to change gear right before the exit of a corner, you could have a lower final drive ratio so you dont need to change gears until you're on the straight. Here are the pros and cons of going to a higher final drive ratio: (say from 3.9 to 4.5) Cons: -Engine RPM while cruising increases... 4500rpm at 100kph is not very comfortable for a daily car! -Potentially more gear changes to get to a particular speed, which makes you slower/the same -1st gear can become useless apart from doing skids, if you now have more torque in 1st gear than traction Pros: -1st gear can become handy for doing skids, if you now have more torque in 1st gear than traction -Reduce the speed range of each gear to suit a new motor or gearbox -Make use of higher gears that were previously only useful at a speed that you cant reach -Fine tuning speed at which each gear is useful to suit corners of a track Changing final drive ratio isnt a magical torque booster though! Better living everyone!

I dont think there's much of a performance loss to having the PCV etc setup correctly. If you're going full steam then the PCV valve is shut anyway, when you're cruising along it's cleaning rubbish/vapours/etc out of your engines crankcase and filling it with fresh air instead. I guess it depends on how likely it is that your engine spits oil out the breather lines, some motors have got a baffled rocker cover which works as a catch can anyway. My motor spits ZERO oil out of the breather lines. So cant see the advantage of not having them hooked up, and plumbing them into the intake seems less work than a catch can anyway.

Isnt the issue that you need a working odometer? What's the reason for GPS speedo not legal, I guess if you're out of range or going through a tunnel or something?

Yeah when temp creeps up, button off for half a lap or so then it's good to go again. That's why I'm looking for alternatives to another radiator... this one is only JUST on the verge of coming to its limit with continuous thrashing, will never be an issue with lack of cooling on the street. It wouldnt need to be constantly spraying, I could put it on an in cabin switch or use a radiator fan switch which engages at a higher temperature than the fan switch perhaps. Refilling a bottle in between runs on the track is no inconvenience at all, it would only need enough for 10-15-20 mins absolute max. If I only turned it on when it started to get hot, it wouldnt need to work for very long at all. It could just be completely turned off while not at trackdays, as not necessary.

Because the airflow meter needs a straight pipe before/after it so it doesnt get turbulence and what not causing incorrect readings. Pretty hard to stick it anywhere else with bends etc.

Yeah that's a good point, I have had 'simplicity where possible' as criteria for things so far. Yeah, I've done the opposite... I've specifically put a rubber seal at the rear of the bonnet line to stop air from coming back IN while travelling at speed, and building pressure in engine bay behind the radiator. Hmm this is true, if it was incapable of cooling the car in every day situations instead of just the track, I'd be almost immediately looking at this option. But since it's just the track where it's the issue, I'm more inclined to see if I can come up with an easier/cheaper way to sort it. If I had to refill a water spray tank after every stint its no big deal... and it would never be required on the road, so no big deal if it stops working.

Rebuilt motor and brand new radiator, so no probs there. Not sure what thermostat options there are. Cheers Nic might give them a buzz at some stage if I go down that route. Only thing is that it needs to be narrow enough so I can still fit my intake out the front, so most radiators are too wide.

Yep that's the ideal scenario I think? The heat energy used to turn the water into steam is removed from the radiator/hot air, and then passed out the back as a gas rather than droplets etc. Although any form of spraying water on to an 80s Toyota is probably asking for rust problems Nah it go out under the car, not over the top. I'd imagine it would only be practical to have a reasonably small amount of water being sprayed. The colder the water is to start with, the more heat energy is sapped from the radiator etc when it turns into steam? I can run a slightly wider radiator, but it would need to be custom made therefore $$$, and the only place it's required is on the track as I'd never see continuous WOT for several minutes while driving on the street. So looking for alternatives. Woops, will get the link fixed.

Mikuni, my thoughts were that if the water spray was a fine mist, it would be drawing heat away but without the massive thermal shock like it would be if you ran a hose on it. Currently the front of my car behind the grill etc looks like this: The cut out to the top left is where the engine air intake comes out, so two main places that the air can go are to there, and through the radiator. Still a few gaps I could probably try seal up though. I think I'll try the water wetter first, as it's the cheapest and easiest possible solution... And it will be beneficial to have it, even if other modifications are required also. I've already got everything required to run an oil cooler as well, and I could mount it in the spare space underneat the air intake in the blanking panel... Could just blank it off for when not at trackdays, so I'm not overcooling the oil during normal driving etc.

Okay, basically the issue I've got is that my radiator is JUST on the verge of not being adequate for track days. After 6-7 laps of Taupo, the temperature starts to creep up slightly... then if I back off for say, 1/2 a lap or a lap, I can go for another 6-7 laps without issue. I've admittedly got a tiny radiator, with only a small coolant volume. Although I realise that moving to a larger radiator is an obvious solution, there are packaging issues which make this difficult, hence small one in the first place. So I've been thinking that a possible solution, (given that this issue only arises at trackdays, and it wouldnt be a constant hassle) could be to run an intercooler sprayer type setup onto the radiator to increase its efficiency, that perhaps switches on at a certain temperature. Is this likely to do acheive meaningful, seeing as how you're using water, onto air, to cool hot water? If it works for an intercooler, should work for a radiator too? Other possible solutions: -Slightly wider radiator for better cooling and more volume. would need to be custom made and therefore $$$ -fit air cooled oil cooler, less work for the factory oil cooler, than runs from the coolant system - already have remote filter kit and lines for this. -Upgrade my heater core to something grunty, turn on while on the track and enjoy the tropical in car climate -water wetter stuff? Does this work? Any thoughts? I think I could rig up a second windscreen washer bottle with a power source easy enough, and try it out.

Hey, Just something else about your diff etc. and getting sorted with discs on the rear. For the brakes on mine, this is what the bracket/caliper looks like: So uses facelift SW20 MR2 rear caliper and bracket, Front disc from a P11 primera wagon, and the bracket that doubles as the bearing holder thing. However if you want all of the above to fit under a 14" wheel (and have better front/rear brake bias) You can use prefacelift SW20 MR2 caliper and bracket, and then you'll need a 263mm x 17mm disc instead of 280mm x 20. If you guys flick me an email address I'll send you that CAD drawing for the caliper bracket.

Perhaps that lower strip was a decal for the sake of being a stone gaurd of sorts.

Except for the roof wing! Cant stand those.

Agree about fibreglass heat wrap being the most useless stuff in the universe, I hate it! Dont think it's anything to do with the quality/cost, more than it's got a short lifespan and is a crappy alternative to alternative shielding. And yeah, 80s Toyotas are always going to have rust somewhere You can never get rid of it all... And even if you did, you'd be buying time, not a permenant solution to the problem of the crappy metal that these cars were made from during that era.

Loving some outside the square thinking going on here, and some of the trial/error research etc going on. Not always gonna come up with a good solution first time around when you're exploring uncharted territory. God knows I've had my share of failed ideas and prototypes before coming up with something I've been happy with, for ideas much more modest than what you are undertaking. Probably not appropriate for this car, but I reckon rear mount radiator is a cool idea! If wanting to keep car looking BTCCish it's pretty hard to incorporate big vented outlets in the rear, haha. In terms of SW20 radiator cooling capacity... I ran an SW20 with no radiator fans running, both on the track and driving around on the road, temperature never climbed above half way. Although I'm not sure if that's more testament to the thermal mass of the large amount of coolant, or the cooling capacity of the radiator.

I've driven a few cars where it's got a floor mounted accelerator, and it is WEIRD having the fulcrum at the bottom rather than top. Might give better control over the pedals if you can just tip your foot rather than move your whole leg kinda thing to operate them, but dunno.

I bare metaled my car, and found that every time there was a tiny stone chip, rust had been spreading out under the paint underneath, there is no way you'd know about this otherwise. In saying this, it's opening a whole other can of worms in terms of potential issues with prepping the bare surface and what not. 80s toyotas are really made of horrible metal, surface rust starts REALLY quickly just from moisture in the air. I would aim to get the whole lot done in as shorter time as possible, either way... If you bare metal and then have primer sitting exposed for 6 months, you end up with heaps of crap in/on the paint which just about makes it a worthless exercise. I had to just about completely resand mine back, on advice from the panel beater because it'd been sitting too long and there'd be too much contamination in the primer. Realistically for a good paint job that is going to last, you want to get your car from bare metal to painted in as shorter time as possible rather than taking a fair amount of time with each step along the way.

I think it looks good on those 16" wheels 14s or 15s look good too, but it doesnt exactly look horrible as it stands.

Always wondered what happened to this car... Freaken awesome to see it's on the mend! Great stuff.

Also, companies just smash out nolathane bushes for everything, with no thought as to whether it causes binding of the suspension, as people just buy them BECAUSE OMFG NOLATHANE. (And rose joints) There's no way you can have a 4 link/panhard with all rose joints, that will not bind when the body rolls... But companies sell them anyway, because people buy them. And yeah, you cant just burn out the bushes because they're contained in a steel sleeve that needs removal too, which can be an utter prick of a thing to do if they've rusted in slightly. replacement rubber is the way to go for the 4 link in my opinion, maybe nolathane/rose joint for the panhard rod only. Avoid rosejoints if you can, it's diminishing gains for a much shorter lifespan until replacement.

Nice one! Are you planning to run it without the supercharger for starters?