Question about drive train
11-08-2005, 01:13 AM
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Question about drive train When I drive slowly in a higher gear just to cruise along, sometimes there's a little "play" at low rpms (around 1,500) and I usually have to press the clutch pedal to stop it, also to avoid bouncing the car forward and backwards (I hope this is making sense). Of course if I use a higher gear at that speed and the car cruises at 2,000 or more, there's no problem.
Before all the mods the car used to have less of this "play" - I can hear it more at the rear end, but it gets loud at times at the gear box too.
It seems like there's too much space between the rear end teeth so when there's no load and the car is kinda sailing the 'clung' noises are louder.
Any diagnostics? Should I have the rear end checked again?
Before all the mods the car used to have less of this "play" - I can hear it more at the rear end, but it gets loud at times at the gear box too.
It seems like there's too much space between the rear end teeth so when there's no load and the car is kinda sailing the 'clung' noises are louder.
Any diagnostics? Should I have the rear end checked again?
11-08-2005, 02:46 AM
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Originally Posted by WS6freak
When I drive slowly in a higher gear just to cruise along, sometimes there's a little "play" at low rpms (around 1,500) and I usually have to press the clutch pedal to stop it, also to avoid bouncing the car forward and backwards (I hope this is making sense). Of course if I use a higher gear at that speed and the car cruises at 2,000 or more, there's no problem.
Before all the mods the car used to have less of this "play" - I can hear it more at the rear end, but it gets loud at times at the gear box too.
It seems like there's too much space between the rear end teeth so when there's no load and the car is kinda sailing the 'clung' noises are louder.
Any diagnostics? Should I have the rear end checked again?
Before all the mods the car used to have less of this "play" - I can hear it more at the rear end, but it gets loud at times at the gear box too.
It seems like there's too much space between the rear end teeth so when there's no load and the car is kinda sailing the 'clung' noises are louder.
Any diagnostics? Should I have the rear end checked again?
I have the same problem right now, However I didn't touch the gears , I put a very big cam and its exactly the same problem... Even when I complete tuning the car [hp tuners] I believe there will be still a little bit of that, but my cam is stupid extreme so maybe if u tune it u might get rid of that. [u can see my cam in my signature]
11-08-2005, 08:36 AM
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Originally Posted by TwoFast4Lv
That would be cam surge 
That is also why you should not lugg the motor down that far
Easiest thing to do is down shift a gear and keep the RPM's above that point.
good luck!
That is also why you should not lugg the motor down that far Easiest thing to do is down shift a gear and keep the RPM's above that point.
good luck!
Now it's much better with the new combo...does't surge at 60 MPH or 2100 RPM's..... 
11-08-2005, 08:40 PM
#6
Originally Posted by jimbob
These guys haven't seen cam surge.....my old combo used to surge up to 70 MPH or 2400 RPM's...Any less and Bad buck...buck... Now it's much better with the new combo...does't surge at 60 MPH or 2100 RPM's.....
Now it's much better with the new combo...does't surge at 60 MPH or 2100 RPM's..... I heard it was that kick *** intake you are running now
11-08-2005, 08:59 PM
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Yep, that would be cam surge. Mine did it too in about the same range before I got the tune perfected. To get it to surge now I have to run it down to under 900 RPM or so in 1st or 2nd gear. Above that it's fine, and also in any higher gear, i.e.- no surge in 6th cruising at 900 RPM.
So yeah, depending on the size of the cam, surge can be tuned out to a greater or lesser extent.
So yeah, depending on the size of the cam, surge can be tuned out to a greater or lesser extent.
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11-08-2005, 09:13 PM
#8
Originally Posted by Silverhawk_02TA
Yep, that would be cam surge. Mine did it too in about the same range before I got the tune perfected. To get it to surge now I have to run it down to under 900 RPM or so in 1st or 2nd gear. Above that it's fine, and also in any higher gear, i.e.- no surge in 6th cruising at 900 RPM.
So yeah, depending on the size of the cam, surge can be tuned out to a greater or lesser extent.
So yeah, depending on the size of the cam, surge can be tuned out to a greater or lesser extent.
11-09-2005, 07:59 AM
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Like everyone said Nick, it's due to cam surge. It's one of those things you just gotta live with to some degree when you start modding for performance. You know, nasty idle, a little gear whine, no traction, killing Cobras....it sucks, but you just gotta! 
Oh, and some people call it bucking, which is very descritpive of the problem. My mom hated it in her 69 Road Runner after me & my brothers had our way with her car. But it was a second faster at the track so she put up with it.
Oh, and some people call it bucking, which is very descritpive of the problem. My mom hated it in her 69 Road Runner after me & my brothers had our way with her car. But it was a second faster at the track so she put up with it.
Last edited by WAHUSKER; 11-09-2005 at 08:14 AM.
11-09-2005, 02:34 PM
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Ah, ok then. TJ tuned the car and it's not super annoying but it's one of those things. In fact considering how bestial the car is now the bucking isn't too bad. It's there, but it doesn't happen in 6th on the freeway (4:11s help).
Sometimes in traffic where there's no space for the bird to flex its muscles this is a little annoyance, but like you said it's a small price to pay...
Sometimes in traffic where there's no space for the bird to flex its muscles this is a little annoyance, but like you said it's a small price to pay...
11-09-2005, 03:08 PM
#11
Just be glad you don't have a locker rear end... when mine gets some cam surge, it can transmit that back through the drivetrain and unlock the locker rather violently. Sounds like the rear end fell outta the car when that happens... 
11-09-2005, 07:17 PM
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I'd say that since you have a cam with similar specs to mine that you should be able to tune out most of your surging, but it can take alot of trial and error. Timing in those surge-cells is crucial, and I found that getting my IAC vs. Effective Area and RAF tables dead nuts on made a world of difference. I've also heard that disabling idle proportional fueling can help, but it didn't have any noticable effect for me.
11-09-2005, 07:39 PM
#13
Cam surge is fun! Makes everyone around you think you cant drive worth a **** until you stick the throttle. Then they 
My old X1 cammed motor had some nice surge around 50-60mph. But the new motor is going to be a surging bitch.
The first time we took the car out after the heads and cam install and it started bucking I didtn know WTF was going on. Ryan looked at me and said "get used to it and yes, its supposed to do that".
My old X1 cammed motor had some nice surge around 50-60mph. But the new motor is going to be a surging bitch.
The first time we took the car out after the heads and cam install and it started bucking I didtn know WTF was going on. Ryan looked at me and said "get used to it and yes, its supposed to do that".
