why with o/d on does the car cut at 110mph ? its at 5500 rpms ... after 4 yrs it still doesnt make sense ...

I've never made it past 107 with OD on the entire time, If I'm going for top speed I usually leave it off until about 119, then turn it on, but then the car doesn't really gain any after that. I made it to about 122 once... I think I have too much stuff in my car.

not enough power/gearing to go higher

I do you mean that it shifts into 4th at 110, instead of hitting 6464 first?

Mine shifts into 4th at 100 with OD on.

our cars can go 100mph in 3rd? wow. that's news to me.

n/a my car maxed out at 118. with all the bolt ons.

As far as I know, 3rd reaches around 115. My speedo reads 120, but I know its off. I made a small program in VB that gets pretty close to determining the top speed of a gear. I fed it info and it gave me 115mph. This is with lockup on, and I have yet to do the final drive gear swap. With lockup off, the car acts very odd when it hits 6464 RPMs, and it won't shift, but it'll only do that if OD is off.

well i have a 97 rs dropped with just a cold-air, i am able 2 hit 116 in 3rd(od off)and have succesfully hit 137mph with od on.if u want 2 go faster you need good engine mods and tires.

Originally posted by EPSYCHOBOB
well i have a 97 rs dropped with just a cold-air, i am able 2 hit 116 in 3rd(od off)and have succesfully hit 137mph with od on.if u want 2 go faster you need good engine mods and tires.

how long did it take?

I can only go alittle faster once I take OD off. My speedo only reads 122, but thats like... 117 or something.

the top speed with o/d off is 128 ... over drive is so flat i dont think it is allowed to go over 5800 rpms

Yeah, top speed with OD on is about 105-108,
OD-off allows you to go up to about 125-128.

The reason is because the engine is too underpowered at the lower RPM. If you downshift by turning OD off, you get just a little more HP in the higher RPM range.

Just look at any dyno graph and you'll see the car makes max HP at the higher RPM ranges. If you're not in the high RPM range, you're not making enough horsepower to overcome aerodynamic drag.

Another aspect to consider is the heat of the transmission. An automatic generates a lot of heat in the torque convertor. If you overheat the tranny, I think the A604 is capable of informing the ECU about it. The ECU might be able to cut back the power, although I've never actually seen this happen on my car.

I've been an idiot lately speeding around at 100+ a lot. I haven't turned off O/D and haven't had any trouble pulling to 110+. The highest I got up to was about 120 but then an RX-8 going 65 pulled over into my lane (the far left lane on a 6 lane freeway) and lets just say it wasn't pretty. I've never topped it out, but with O/D on it doesn't seem to have any trouble pulling over 110.

This is incorrect, I have hit speeds in excess of 125 MPH with the overdrive on. I always drive with the overdrive on to conserve gas in the city and with it on I am consistently pushing speeds higher than 120 MPH.

Technically... if you leave OD on, and you had enough power, you could top out forth, or whatever.

While leaving OD on though, the tranny shifts into 4th at 100 or so. 3rd still has a while before it has to shift. The program I made gave me about 115, but my speedo reads 120 when 3rd hits 6464RPMs.

A big problem is that the speedo isn't really 100% correct at those speeds... so... basically, the way I understand it...

1st -- ends somewhere around 40mph
2nd -- ends around 69-72mph
3rd -- I guess 115 - 125, It's hard to tell with the speedo being off.
4th -- Ok, with my program... I put in the info, and it gave me 165mph, now, since the speedo is off, it was off when i put the info in, and it was off when it came out, so probably 155 - 170 mph... or something, if anyone wants to correct me, go for it, I'm just trying to be helpful.

Originally posted by thedawg
Yeah, top speed with OD on is about 105-108, OD-off allows you to go up to about 125-128. The reason is because the engine is too underpowered at the lower RPM. If you downshift by turning OD off, you get just a little more HP in the higher RPM range. Just look at any dyno graph and you'll see the car makes max HP at the higher RPM ranges. If you're not in the high RPM range, you're not making enough horsepower to overcome aerodynamic drag. Another aspect to consider is the heat of the transmission. An automatic generates a lot of heat in the torque convertor. If you overheat the tranny, I think the A604 is capable of informing the ECU about it. The ECU might be able to cut back the power, although I've never actually seen this happen on my car.

iirc,
if the tranny starts to overheat it locks up the TC to cool it down

Ok, I was messing around today, and got some new info, I put in new speeds and got about 143.5 as the top speed of 4th, lol.

So we can say its somewhere in between 140 - 160 :P

how much power is required to move the planetary overdrive gear though ? thats the question ...

Mine will hit about 120 with OD off then flip it on and my speed will read around 135 so figure about 127 or so for me.

this isnt really on topic, but why in the hell would you need to be going THAT fast?

I did ONCE on a huge flat open piece of highway racing, and beating an RX8 , hit 120 ish, and felt really dumb when I reaized I was going that fast. I am a very compable driver but even at the speed the slightest mistake can spell catastrophy. MY OD was on, flipped off till4th then flipped back on ,but Im boosted so your milage may vary

just think of it like this imagain what happens when you are going say 55 and you turn the wheel ok double the speed and double the reaction and that is what happens. going that fast in a non controlled situation is absolutely ridicoulus (sp.).

actually the top spd this trans can handle is 182mph....
however we do not have the rite amount of power to go upwards 140 on a strait away. (if u claim 141+ u were going downhill and u can bullshit me, *u guys know this*)the amount of tourqe needed would have to surpass your max hp to keep climbing in OD.ie: if u have say 150 hp at the wheels and about 140lbs of tourqe (this would be a beefed up vers. of our cars) you will need to get approx 280lbs of tourqe and 300hp to max out 4th gear (get it to continue to climb) (unless like i said going downhill or drifting)this is a 3klbs car people. Our cars have no governer on them... so in retrospect they made 4th gear (od) almost impossible to redline.

MRINFiNiT3
aka
THA ATX GOD
02:19:18pm DarkOne> They'd have had to brought a whole fucking JUG of KY.
02:19:28pm InFiNiT3> lol no shit
02:19:39pm DarkOne> and a funnel.
02:19:45pm grain> have to get the ky with warming
02:20:00pm InFiNiT3> i feel sorry for the 18 y/o (one was 17 one 18) his name was plaster'd all over the news n news paper
02:20:06pm DarkOne> Yeah, has to be warming.
02:20:06pm BuckNutty> jus spit on it and it'll go in
02:20:17pm InFiNiT3> aye the ky w/ warming any good>
02:20:45pm grain> never tryed it
02:20:50pm grain> i applyed for a sample on thier website
02:20:56pm BuckNutty> evan didn't complain any
02:20:56pm BuckNutty> it felt nice
02:20:57pm InFiNiT3> lol
02:21:01pm grain> i use id glide whne she dries
02:21:06pm grain> good stuff
02:21:45pm InFiNiT3> thnx for the new sig guys
02:21:45pm DarkOne> Are we still talking about fucking dead chicks?

oh and by the way...
im waiting for u guys to flame me for my post
feel free....
in the long run... im rite :)

Mr.InFiNiT3
aka
THA ATX GOD

02:19:18pm DarkOne> They'd have had to brought a whole fucking JUG of KY.
02:19:28pm InFiNiT3> lol no shit
02:19:39pm DarkOne> and a funnel.
02:19:45pm grain> have to get the ky with warming
02:20:00pm InFiNiT3> i feel sorry for the 18 y/o (one was 17 one 18) his name was plaster'd all over the news n news paper
02:20:06pm DarkOne> Yeah, has to be warming.
02:20:06pm BuckNutty> jus spit on it and it'll go in
02:20:17pm InFiNiT3> aye the ky w/ warming any good>
02:20:45pm grain> never tryed it
02:20:50pm grain> i applyed for a sample on thier website
02:20:56pm BuckNutty> evan didn't complain any
02:20:56pm BuckNutty> it felt nice
02:20:57pm InFiNiT3> lol
02:21:01pm grain> i use id glide whne she dries
02:21:06pm grain> good stuff
02:21:45pm InFiNiT3> thnx for the new sig guys
02:21:45pm DarkOne> Are we still talking about fucking dead chicks?

Wow, 182. I was off. My little program would be much more accurate if I would get the true speed and true RPM. It was more or less correct with the other 3 gears though.

yea u can without a doubt tell the o/d can climb to higher speeds ... but being a planetary od gear that it is ... it must need much more power to raise itself to those speeds ... much harder to move the o/d than the regular gears imo...

ya our o/d gear is alllll screw'd up.... ill fix it one day lol when ive got more funds
i killed my last grant on this trans im running now



02:19:18pm DarkOne> They'd have had to brought a whole fucking JUG of KY.
02:19:28pm InFiNiT3> lol no shit
02:19:39pm DarkOne> and a funnel.
02:19:45pm grain> have to get the ky with warming
02:20:00pm InFiNiT3> i feel sorry for the 18 y/o (one was 17 one 18) his name was plaster'd all over the news n news paper
02:20:06pm DarkOne> Yeah, has to be warming.
02:20:06pm BuckNutty> jus spit on it and it'll go in
02:20:17pm InFiNiT3> aye the ky w/ warming any good>
02:20:45pm grain> never tryed it
02:20:50pm grain> i applyed for a sample on thier website
02:20:56pm BuckNutty> evan didn't complain any
02:20:56pm BuckNutty> it felt nice
02:20:57pm InFiNiT3> lol
02:21:01pm grain> i use id glide whne she dries
02:21:06pm grain> good stuff
02:21:45pm InFiNiT3> thnx for the new sig guys
02:21:45pm DarkOne> Are we still talking about fucking dead chicks?