Roman

If the parts are available, that sounds like the easiest possible option! I'd only bother making custom shit as a last resort when there's no other option.

But then how does it know if it's on the firing stroke or exhaust stroke with only a crank angle sensor - Aahhh wasted spark and batch injection, problem solved haha. Is that a Straight six engine in the beemer Dave?

Ugly cars are the way of the future though! Yeah if the Gemini was too bigger a project then I guess it makes sense to scale things back a bit. If you give up on this one though I am going to revoke your mancard, give you a kick in the balls and ban you from any further projects!

I think it's more to do with difficulty in controlling super small pulsewidths? As in, your ECU cannot control below 2% opening time. (for example) That might be fine for 350cc injectors as 2.5% pulsewidth gives you correct idle. But 560cc might need 1.5%, which your ECU cant do. Or whatever.

Aahhh shitballs, my exhaust hanger rubbers broke while doing some Scenic driving today. This might expedite my exhaust remake, but at the same time I'm not keen to reinvent the wheel just before trackday next weekend. So I'll just get some replacements, they last about 5,000kms before breaking haha. It would have been the highish speeds on bumpy roads that did it, the rear muffler is reasonably heavy and was probably jumping around a bit to make it break. I've come up with a good idea for an easy way to make exhaust hangers though, I'll use nylon blocks or something to replace the rubbers while I'm making it, so it's not wobbling around and I can try fab everything to the same distance between upper hanger and lower hanger thing that the rubber bush will go on. If there's consistently a 50mm gap or whatever then it will be less likely that there's just one that's taking more of the load than the others.

Haha yep. It makes driving a toyota echo considerably more entertaining on long trips. Im all like "4.5l PER HUUNIT, CHEAH BOY!" *gang signs*

Yeah, stock ECU. Torque is such an awesome app! I've got a few different screen presets setup which are handy. One I use when I'm trying to be stingy driving my Echo, with realtime and average fuel usage values, a tacho and one or two other things. However I've got a few other screens with like ignition advance, intake temp, coolant temp, tps, etc etc which are infinitely useful for troubleshooting and figuring out what the ECU is 'thinking'. Even if you use only one gauge it doesnt really update quick enough to be used in realtime as a tacho or whatever though. I've found that in any car that I've driven, about 80-85kph is the most economical speed... It's the cross over point between keeping engine rpms low in top gear, aerodynamic drag and keeping the speed high for the amount of fuel you are using.

Only in first gear, as that's the only time you're out of the powerband. But there's generally an abundance of torque in first regardless. After that you're at the mercy of your gearbox ratios and how many rpms it drops between gear changes. If the problem is that at 5500rpm you've got no power, and it dips to that rpm, it's the gearbox ratios that will fix the problem not the final drive. If you shift at redline each time, it's still going to drop by the same amount of revs per gear change regardless of final drive ratio. A 4.66 helps you get out of the slump in first gear, but that's it. It moves the peaks, but it moves the troughs too. I'll put together a technical illustration later with MSpaint to explain further

If you fit something like a 4.7 ratio but your gearbox isnt able to shift any faster than it did before you have this problem: It's normally (for example) 3 seconds accellerating through 1st, 1 second gear change, 4 seconds through 2nd, 1 second gear change, 5 seconds through 3rd, 1 second gear change, 6 seconds through 4th. total time 3+1+4+1+5+1+6 = power to the ground 85% of the time. Then with a modified final drive you end up with: 2 seconds accellerating through 1st, 1 second gear change, 3 seconds through 2nd, 1 second gear change, 4 seconds through 3rd, 1 second gear change, 5 seconds through 4th. total time: 2+1+3+1+4+1+5 = power to the ground 82% of the time. Since you're spending less time putting power to the ground, if my shoddy maths is correct then in the above example it's the equivilent to losing 4.5hp across your powerband on a 150hp engine. You get the illusion of more power since it gets through each gear quicker, and feels racier, but you end up slower overall. It gets even worse if you were previously topping out your speed in the 1:1 gear (fourth) but now shifting into an overdrive gear instead which has a higher transmission loss. Race cars which have close ratio gearboxes and high final drives generally do so in conjunction with a gearbox that can smash through the gears almost instantly, and an engine redline that's much higher than a standard one. Also the top gear is generally a 1:1. As otherwise it's not worth the extra time spent chopping through the gears. It's a bit more complicated when it comes to a track with corners, but personally I dont think changing final drive ratio acheives as much as people tend to think.

Do you still have the gemini as well?

I've had a mix of problems for a while, where the engine runs good under full load, but is a total dog at cruising or idle. I've been chasing around just about everything trying to figure this out. Well, it turns out that I've had the wrong knock sensor, which has been causing the chaos! When knock happens, it makes a certain frequency vibration in the engine block. The frequency differs depending on the bore and stroke, similar to how a trumpet makes a different sound to a big tuba or something. So the problem that I had, was that I had a knock sensor from a smaller engine. It was listening out for knock on a different frequency, and not hearing it when it happened. The ECU thought everything was dandy, so was smashing in shitloads of ignition advance because it thought I was running some wizard magic fuel that appreciates 50 degrees advance in all scenarios hahaha. Today though, I managed to find a knock sensor from a gen 3 3SGE at Zebra. Got home and swapped this over, reset the ECU and disabled all changes from the fuel computer. Took it for a run, and... sweet jesus! Idle problems and low load problems instantly solved. Idle has gone back down to 10 or so degrees advance, and the idle is stable at 950-1000rpm when previously it was running 12-1300. At low load cruising it's now doing 30-35ish degrees advance instead of high 40s. I took the car for a bit of a run out to the airport and back, the average for the trip was 8.5litres per 100km. Which is a lot better than the 11/12l per 100 that it was getting before. It can now sit in 6th gear trundling along at 1600rpm or so at 50-60kph with no worries. Previously I'd have to go to 4th or 5th. Pretty happy with the economy! It's a lot quieter in the cabin when the motor is running properly too, so pretty happy all round. An unexpectedly successful fix! Taupo trackday is next weekend, and I caaaannnnnn not wait

How did it fare with the different ratio for the diff? Do these run some wizard magic imperial handspan type wheel PCD, or is it easy enough to get a second set of wheels. I'm down in Taupo next weekend I'll come say Hi if you'll be around.

Wheel size of 260mm dia means it travels 816mm per rotation 1225 rotations per km To go 30kph = 36764 wheel rotations per hour 612 wheel rotations per minute So if your engine can do a max of 3600rpm (3600 / 612) You would need a 5.88: pulley ratio between the motor and the wheel. Assuming you had the torque available in the lower rpm range to get you there.

Keen!

Yeah I didnt notice that last time I bought a set, (On MR2) but they did feel a bit squishy on the Carina until I added the camber. It's kind of like going from an old set of skate shoes where you can feel everything, to full soles again. Heh. Either way, gave them a bit more of a scrub tonight around scenic drive and the car is going sooooo good! 4 weeks till Taupo trackday, if it's dry I'll definitely smash my 2.03 Carina lap record and hopefully come close to / beat my 1:57 MR2 record on full track. I've had a moment of clarity about a few corners I've been doing wrong as well, and will bring a pyrometer to bump the camber in or out a bit on the day depending on what the tires are doing.

Lice Lice Baby?

Keep the spoiler for sure! Any idea on colour you'll go for.

UJ I bet you only ditched the booster because it didnt work after you drilled weight reduction holes in it

Yes standard rubber in the rear, apart from the panhard rod which is rose jointed both ends. Tonight I added what I will assume is 2 degrees of camber to the front, and went for a bit of a doort. Steering is back to being good with a little camber now! And it doesnt hit the gaurds at all with the wider tires. My 0-100kph time is probably half of what it was a week ago... Just a quick chirp then it's off. awesome. My shocks arent anything too fancy but my front to rear spring rates seem okay at the moment. Dont really want to go any stiffer on springs, might get some better shocks one day though. After driving it tonight I dont think a rear swaybar is required, it's handling great.

Soooo I got some T1Rs fitted yesterday, now running 205/50/15 all round instead of 195/50/15. Some may dissaprove of a 205 on a 7" rim but such is life haha. Car feels so much different! Previously had Bridgestone RE001s on front and Direzzas on the back. It has soooo much more grip now! Even without traction brackets I can hoof through 1st and 2nd without wheelspin which is great. One unexpected thing though is that turning has become a bit more sluggish and it understeers a lot more. The front/rear balance has previously been pretty good (if not on the oversteery side) with less grip. Which is why I've never fitted up the rear swaybar. But now that grip levels have increased it might be time to look into fitting it to get the balance right again. So I'll get that underway and increase front camber in 1 or 1/2 degree increments till turns nicely again. Might dump some friction modifier oil in the diff as well. Either way I'm pretty stoked to have some decent grip! Cant wait to drive it again after work today.

This is basically what I read this thread as Drive with your booster disconnected currently, and that's exactly what it will be like using your current MC without a booster. You'll probably find the pedal is way too hard. The only way to improve this is to change the ratio of fluid pushed by the MC per CM of pedal travel. (Or fit a booster haha) So you could: -fit a smaller MC (But it might reach the floor before you acheive full/desired level of braking) -Change the leverage point where the MC attaches to the pedal (Same problem as above) -Make the pedal travel longer for same amount of MC piston movement (Although you can only increase so much until impractical) Basically it seems like a big kick in the balls for not much gained, and will take some experimenting to find out what works well for you. I'd just leave it as is then go do some hoonage

OK thanks! I dont expect it to be a quarter mile champion or anything, but it's embarassing that my Toyota Echo would probably drag it off from the lights at the moment haha.

I'm hoping to acheive the opposite with traction brackets hahaha. Currently the car can only put down probably like 50-80hp before it spins the wheels in first or 2nd gear. Sounds fun but when you try to pull out of a side street into a gap in traffic and just blaze the wheels eeeevery time and dont move it gets pretty old! My lower 4 link arms are *just about* level, they currently point slightly upwards towards the diff. With traction brackets I should be able to get them pointing down towards the diff instead. Which should push the diff down into the ground on accelleration, rather than lift it up... hopefully!

Uuuuggghhhh Davy those wheels on your Carina were soooooooo good. Worth a pretty penny these days! Do you know what happened to yours in the end?

Woooooot! Car's all back together, and HOLY SHITBALLS! It drives so much differently with the LSD adjusted. Previously, you would make a suggestion along the lines of "Please, may we turn this corner" and the car would be all like "FUCK YOU BATMAN" then you're all like "NO FUCK YOU" and then it turns. where as now, the steering effort seems about half, and it turns in soo soo much better. It doesnt single wheel peel either, and the diff noise has completely vanished so great success all round! It's still got miserable traction, but I'm due a set of fresh tires. Traction brackets might be the only thing that will really help though. I've been looking at the options of either R888, Toyo Proxes T1R, Achilles 123 or Nitto NT01. It's just a toss up between whether I want faster laptimes but shittier to drive any other time, or nice to drive but overheating tires. I think for now I'll go with the T1Rs (which I've used previously and found to be awesome) and then keep an eye out for a spare set of wheels that fit before getting semis perhaps. Either way, pretty happy right now! Fred: //oldschool.co.nz/index.php?/topic/21625-romans-cod-piece