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Manual Shifting on FMX
#1
I started to track my car and its a lot more better to pop it in first and run up than to just leave it in drive. My question is, is this harmful to the tranny? Its a 302 with roughly 350-400 HP with a FMX and 3.08 gears..driveshaft and axle still stock w/ 8" one legger.

1972 Satin Black Coupe, turns better than average, goes vroom with 303 RWHP.
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#2
I don't think it would be harmful to your tranny. You would probably have engine issues before tranny issues. Do you use a tach, and if so, when do you shift?

Doc

[Image: 6y14ea.jpg]

Project started 8-7-10
Completed: All new suspension, rebuilt 351C H Code bored .030 over with mild cam and intake, new 3.50 TracLok, custom exhaust system
Current "mini-project": interior upgrade Undecided
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#3
Not harmful until you blow past drive into neutral or reverse on a power shift.

You'll know the meaning of something wonderful then, boy!

73 conv. 460, D0VE large valve heads, Performer RPM manifold, Voodoo 227/233 cam, Holley 950 HP carb, C6 trans, 3.25 trak-loc.
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#4
The FMX was designed to be manually shifted without issue. The 1-2-D pattern was a departure from previous trani's. you can start in second on ice to prevent wheel spin, you can keep in first to keep the rpm up and shift to second to chirp the tires...no problems.
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#5
@73vert i usually shift about 4-4500

oh wonderful ok i was worried ill blow the tranny before i can afford an upgrade haha

1972 Satin Black Coupe, turns better than average, goes vroom with 303 RWHP.
  Reply
#6
oh dam;153830 Wrote:@73vert i usually shift about 4-4500

oh wonderful ok i was worried ill blow the tranny before i can afford an upgrade haha

You should be in great shape shifting manually. I occasionally shift between 5500 - 6000 without issue with my newly rebuilt 351C.

Doc

[Image: 6y14ea.jpg]

Project started 8-7-10
Completed: All new suspension, rebuilt 351C H Code bored .030 over with mild cam and intake, new 3.50 TracLok, custom exhaust system
Current "mini-project": interior upgrade Undecided
  Reply
#7
i have 302 that was built roughly 2000 miles ago. Would i be fine going to 5-5500?

1972 Satin Black Coupe, turns better than average, goes vroom with 303 RWHP.
  Reply
#8
oh dam;153906 Wrote:i have 302 that was built roughly 2000 miles ago. Would i be fine going to 5-5500?

I don't know squat about 302's, so I wouldn't want to speak out of turn. Post up the question in the Performance forum and you should get a few replies from people who know what they're talking about. Smile

Doc

[Image: 6y14ea.jpg]

Project started 8-7-10
Completed: All new suspension, rebuilt 351C H Code bored .030 over with mild cam and intake, new 3.50 TracLok, custom exhaust system
Current "mini-project": interior upgrade Undecided
  Reply
#9
Not guidance, just my experience. I had no problems at 5K but that was pushing it. At something less than 5500 (manually shifting a C4), I sprayed the rocker arms and dropped a valve. Destroyed the engine - head, piston, and block. Hydraulic lifters start to get too much bounce. If you're running solid lifters, guide plates, threaded studs, etc, different story.

From my experience, I'd stay below 5K or else you may find this when you tear it down after it is towed home!


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#10
ouch!! i got some roller rocker arms, hyper-eutectic pistons, and im pretty sure they are hydraulic lifters since i dont need to be adjusting them.

1972 Satin Black Coupe, turns better than average, goes vroom with 303 RWHP.
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