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jimGTS wrote:mr2nut123 wrote:Signori wrote:Fancy putting mine up?
CT20b
1bar of boost
standard rev3 engine
Come on Jim, wake up.
i can, but it wouldnt show anything those pics already dont show, lol
Kongaroo wrote:
Ryan
Quite interested before my next upgrade to ge the best results.(top) ratio is 1.1 also known as direct top, the Mr2 has a 4th gear ratio of around 1.028, but 3rd is around 1.328.(there may be others) the 4.1 gives quicker exceleration and a higher RR Bhp figure.- lower profiles reduce the gear ratio more than taller profiles, so ditto the above.Mike N wrote:Multiply the gear ratio by the known bhp figure.
The lower the gear the higher the power to the wheels.
Lower diff ratio does the same thing.
Typically a 4th gear
Mr2 diffs range from 3.9 to 4.1,
Tyre circumference
Interesting! 
- it was infact the opposite, his main concern was mapping a reliable set up, which is just what I wanted to hear. Personally I prefer driveability over peak power anyway.(eg. dynojet) and eddy current dynos (eg. Dyno Dynamics) I think I've more or less come up with the answer to my own question.(eg. 3rd) will accelerate more quickly than a higher gear like 4th. However this shouldn't affect the dyno power readings because the dyno knows what RPM or speed the car is travelling at. So while a lower gear might well generate more torque the dyno should not display a power difference because of it due to the overall lower speed achieved in 3rd gear. This should mean that the differences we are seeing are down to differences in the amount of power lost rather than faster acceleration. This was because the rate of acceleration is slower in 4th gear which means inertial power losses will be lower. In other words it takes more power to accelerate the gears, drivetrain etc. quickly rather than slowly. In fact had the car been on an inertia type dyno like the Dynojet I suspect I would have had better peak power figures in 4th gear because of this. Ie. peak power recorded on an inertia type dyno will actually be higher using a larger diameter tyre as the car will accelerate more slowly. Sounds a bit weird I know but there's actually quite a lot of information on the internet that supports this. The DD uses a linear rate of acceleration which I believe will mean unlike the Dynojet the amount of inertial power losses through for example the gears should not change. So where does the extra power loss come from in 4th on a DD? Although some types of eddy current dynos do add in a correction factor to account for this I don't know whether this is the case with the DD. .- could it be something simple like the really big power cars are more likely to have traction problems on the dyno in 3rd? So there may be wheel spin or perhaps the car may need strapping down more firmly than normal? What did Paul give as the reason btw?- ie. less load, heat, shorter pulls etc. However it's for these very reasons that I prefer to use 4th on the dyno because I want the car to be as heavily loaded as I would realistically see in regular use so as to be sure that the car drives nicely and without knock in those conditions. Well that's my take on it anyway .i was happy any way.... i did quiz Ryan on this and Ryan uses 3rd to make the runs shorter so there is less heat build up in engine bay .
black gts wrote:when my mr2 went on a dynamatics the operator used 3rd and then someone on here said that he should use 4th
but.
as with a front mounted engine is getting the full blast of cold air from the rolling road fan
hth
Paul
Between 15-25bhp and 10-15fp torque seems to be added to the 3rd gear run as it has a higher gear ratio and spins up the dyno a bit quicker. Can't wait to get my 3rd gear run in for a fair comparrison. Airflow ain't an issue when you've got a ha-uge boot mount hanging low with a fan / Rev 3 / 2.0 bar / V-Power/ Chargecooler / Motec
- Rapid GBKongaroo wrote:Dang.
406bhp for the win! 
(1:3 from what I can remember?). I made an additional ~20hp and quite a bit more torque in 3rd today so I think it's fair to say that it's either these engines or possibly a combination of them and smaller turbos that make a fair bit more power in 3rd. 
. Up to about 6k there was already a good spool and power advantage before getting to peak hp. I'll definately nip back down once the clutch is sorted and get a quick power run for sure. You wouldn't wait for spool, you would drop into your powerband as you would with any sports car. I must admit, I went with this turbo for spool initially, and I realise it's no GT28RS now with the cams, but the addiction for neck braking top end like this has got the better of me now The car feels absolutely INSANE compared to before! The torque curve remains solid up top with hp increasing to redline which makes my previous 'high peak midrange map' running standard cams feel stupid when driving her now. I was running quite lean before between 3 and 4k so I would put the spool difference mostly down to this as it was mapped very safely. I guess we can all map aggressively to show off but i'd rather keep temps down and drive it to be fair All on V-Power with no addatives or meths too. 
jimGTS wrote:hi, sorry ill get these uploaded during the week
so was this still 4th gear, but with your hks 264s now?? correct?
same 1.5bar? or more boost?
so the cams have given you 30hp, but slower spool correct?
Same boost and gear as before, still makes 394bhp at 1.4bar which is great too as it still makes more power and more importantly, holds the torque curve up top. My previous setups not in the same league once on the road in the powerband! We have seriously played safe on this map which is the main reason for the big loss. With the AFRs same as before, they would have estimated only a few hundred rpm loss of spool too.Kongaroo wrote:Hey Jim, any chance you can put my TD06 and GT28RS graphs up for a little while so I can have a quick comparison for my own interest like you did for MR2nut?
Green is TD06 at 21.2 psi, red is GT28RS at 22psi:
Would be interested to see how lean it is bottom end.
... 
wadeski wrote:
Check out those AFRs.
Spool is slower but I guess it's nice and rich through the entire rev range!(BP ultimate or V-power), uprated injectors 
jimGTS wrote:hi, sorry ill get these uploaded during the week
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