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-   -   Downshifting into 1st: Should it be difficult? (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/downshifting-into-1st-should-difficult-481032/)

Buzzardsluck 11-11-05 12:21 PM

Downshifting into 1st: Should it be difficult?
 
Heres the info: I was test driving a 94 and while test driving it I tried to downshift into 1st while going 5-10 mph and it was less than smooth. I tried again 3 times with the same results. I tried once without rev matching and the last couple times trying to rev match. The car has no problem going into first when stopped. There were no problems downshifting into any other gear. The rest of the gearbox is perfect. The car has 81000 miles, original transmission, new clutch/pressure plate.

Here's my question, is this normal? The guy told me it was and I believe him but I love second (and 3rd, 4th) opinions. Please note that I normally drive an RX8 which has very smooth shifting up or down. He also stated that the gears in a RX7 are square and the gears in the RX8 are rounded :dunno: . Thanks for the help in advance.

Yes, I searched before posting :)

Nghtstlkr7 11-11-05 12:30 PM

most cars have a sort of "lockout" feature to protect the drivetrain. it prevents you, or makes it very difficult, from shifting into 1st gear while the car is moving faster than a few miles per hour.

from what i understand this is the deal with quite a few cars.

dgeesaman 11-11-05 12:37 PM


Originally Posted by Buzzardsluck
Heres the info: I was test driving a 94 and while test driving it I tried to downshift into 1st while going 5-10 mph and it was less than smooth. I tried again 3 times with the same results. I tried once without rev matching and the last couple times trying to rev match. The car has no problem going into first when stopped. There were no problems downshifting into any other gear. The rest of the gearbox is perfect. The car has 81000 miles, original transmission, new clutch/pressure plate.

Here's my question, is this normal? The guy told me it was and I believe him but I love second (and 3rd, 4th) opinions. Please note that I normally drive an RX8 which has very smooth shifting up or down. He also stated that the gears in a RX7 are square and the gears in the RX8 are rounded :dunno: . Thanks for the help in advance.

Yes, I searched before posting :)

The RX-8 does indeed have much smoother synchro engagement than the FD. It also handles much less torque :) This is a normal tradeoff. I don't know why the gears would be different - the FD uses helical cut gears that are always engaged. It uses single synchros for 1, 4, 5, R gears, and double-cone synchros for 2, 3. The RX-8 I think uses more double and even triple synchros.

First gear has no lockout feature of any kind, however, it is not always easy to engage while rolling. It is not a bad thing to do, provided the car is not rolling fast (10mph sounds ok) and you don't force the shifter into place. Generally there is no good reason to go into first quickly while rolling, so no big deal.

Dave

Buzzardsluck 11-11-05 12:48 PM

^^thanks for the response. I'm going to buy the car but just wanted to double check about the gears since I've read about some gear problems w/the 7. You are correct it isn't a big deal.


Ah, it feels good to get my first technical post out of the way (many more to come I'm sure once I get my hands on the car!)

afgmoto1978 11-11-05 12:56 PM

I have the same feature on my FD, even after the recent rebuild from Pineapple. Don't worry about it, that's normal.

RX 4 Speed 11-11-05 03:14 PM

normal...

just downshift to 2nd, then just coast to a stop after that, in neutral if you wish...

1QWIK7 11-11-05 03:44 PM

i get that alot too..

like when i know i have to slow down, ill put it to neutral, then when im about 5-7mph, traffic starts to flow and im like fuck, try 1st and it doesnt want like it blocks me..

so i either put it to 2nd and rev a bit higher so it doesnt bog or i force 1st (i know its bad) or sometimes i clutch out, then clutch in and it goes into 1st (dont know why it works like that..

Tom93R1 11-11-05 05:41 PM

If you double clutch it will probably go into first more easily, but there really isnt much reason to need that any way. Sounds like the normal 2->1 shift in my FD as well.

MazdaSpeed93 11-11-05 06:16 PM

Mine wont let me shift into 1st until i'm going like 2mph or stopped, well it does but kinda tough to get it in.

mecman 11-11-05 06:58 PM

Same here. If the car is not at 3 mph it will not go down to 1st. I know that is correct because my trans was rebuildt due the 5th gear synchro problem.

4CN Air 11-11-05 07:04 PM

if you want to test the cars synchros quickly sift from 3rd to 5th and listen for a grind. That's the FD synchro that causes the most trouble.

quid 11-11-05 09:45 PM

No manual transmission that I have ever worked on has had synchros for first gear and reverse. They are designed that way purposefully. THe car is fine. The other guy is correct with the rx-8 feature--it is a smoother shift but only because it has no power, not because the tranny is nicer. The synchronizers are what match the gears to the required speed of the input shaft. Without synchros (which is the case for first and reverse), the only other way is to match the speed manually with the throttle.

If this is the only issue with the car, I would go ahead and buy it. Make sure you post some pics afterwards. It is like when my friends get a new woman. I make them bring her over to the house for the 'showing.' I hope this helps.

Quid

quicksilver_rx7 11-11-05 10:13 PM

I'm not a tranny hard hat here, but I've always been told, and maybe even read somewhere that it's not really bad (but all the same) not really good to shift into 1st while rolling because it does envoke some stress on the the tranny. A friend of mine's RX-7 will grind if you shift into 1st while rolling. Probably has something to do with the "wear" factor.

Joe

dgeesaman 11-12-05 07:57 AM


Originally Posted by quid
No manual transmission that I have ever worked on has had synchros for first gear and reverse.
Quid

This tranny (the R15M) does have first and rev synchros.

Dave

Retserof 11-13-05 04:49 PM

You have to go back a long time to find a car that does not have syncro in first. I had a 1961 Triumph TR-3A like that. You had to be stopped to shift into first unless you really knew what you were doing. I replaced the tranny with a full syncro 4 speed from a TR-4. Big improvement.


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