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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: greenmonster on December 22, 2007, 09:48:57 pm

Title: Shift points
Post by: greenmonster on December 22, 2007, 09:48:57 pm
At full throttle my truck shifts 3500-3800 rpm is this normal.I reved the motor in park and it can hit 6000rpm at about 6200-6300 I think the valves started to float.
Title: Re: Shift points
Post by: zieg85 on December 22, 2007, 10:13:40 pm
My '08 Escape Company Car shifts at 6000 from first to second when it is wound up tight. 
Title: Re: Shift points
Post by: 76_Scottsdale on December 22, 2007, 10:45:11 pm
Sounds ok to me. Any higher then that it feels the motors gonna tear outta the hood. Are you wanting a higher shift point?
Title: Re: Shift points
Post by: greenmonster on December 22, 2007, 11:21:05 pm
It seems to me that there is alot of motor left.I figered i should use it.I would like for it to shift at 4500 rpm.Idon't want to push it past 5000rpm even though Igot it to hit 6000rpm. It has a weiand stelth intake,holley carb,mild cam and duel exhaust with flowmaster 40's.
Title: Re: Shift points
Post by: 76_Scottsdale on December 22, 2007, 11:25:25 pm
I would suggest getting a shift kit installed then. They're only about 50 bucks but it's about 150 to have it installed in the vehicle. You can alter the shift points and it also make them more solid. Be careful on free-reving the motor, It's a good way to float a valve and smoke it. It's not just how high your motor will rev, it's how high it will rev safely.
Title: Re: Shift points
Post by: greenmonster on December 22, 2007, 11:29:13 pm
IT has a shift kit in it i didn,t put in in it was in there when i bought the truck.When it shifts in to second it will brake the tires lose.
Title: Re: Shift points
Post by: 76_Scottsdale on December 22, 2007, 11:39:16 pm
If it's breaking the tires loose shifting to second, then I don't know what more you could want  ;D
If it's already got a shift kit then IDK
Title: Re: Shift points
Post by: greenmonster on December 22, 2007, 11:44:09 pm
another thing it that it won't kick down out of third gear above 40mph is that normal
Title: Re: Shift points
Post by: greenmonster on December 23, 2007, 12:01:18 am
thanx for the help 76 talk to you later.
Title: Re: Shift points
Post by: FlatBlack77 on December 23, 2007, 12:52:28 am
when I had my stock 400 small block in my truck when I first got it it had a shift kit that had just recently been installed along with a tranny rebuild. at full throttle it would rev to about five grand and chirp the tires every shift. 3800 sounds really low.
Title: Re: Shift points
Post by: 76_Scottsdale on December 26, 2007, 01:43:59 am
If your tranny doesn't wanna shift out of 3rd above 40 I would check to see if your kickdown cable is installed properly.
Title: Re: Shift points
Post by: VileZambonie on December 26, 2007, 09:00:06 am
What transmission do you have? If you have an early shift (not including the TH400) adjust the TV cable tighter. If you have a TH400 replace the modulator with an adjustable one and check your detent solenoid.
Title: Re: Shift points
Post by: greenmonster on December 26, 2007, 08:04:28 pm
I have 350 trans.I adjusted the cable by releasing the clip and opening the throttle all the way and pushing the clip back in.Is there another way to do it or some sort of trick you could tell me.THANKS for the help it is alot easier getting things fix with you guys and GIRLS on this site.
Title: Re: Shift points
Post by: VileZambonie on December 26, 2007, 09:40:54 pm
You went the wrong way with your cable. Depress the tab and push the pluger towards the firewall. Then depress the throttle WOT (engine off) and that's your base adjustment.
Title: Re: Shift points
Post by: greenmonster on December 26, 2007, 09:52:47 pm
I don't understand what you said.AT full throttle I can still pull the cable out 1/2 inch,is that to much.
Title: Re: Shift points
Post by: VileZambonie on December 27, 2007, 07:52:14 am
To adjust the TV cable make it so the plunger is pushed in towards the firewall. This will tighten the cable between the bracket and the carburetor. Leave it locked like that. Then push the gas pedal all the way down. The tension on the cable will pull it out just enough to give you a base starting point. If you want earlier shifts lengthen the plunger, later shifts shorten it (towards your firewall). In other words the cable should be locked when you depress the throttle.

There's a zillion websites on tv cable adjustment.
ex http://www.technicalevolution.com/tv.htm
Title: Re: Shift points
Post by: jonkmbll89 on December 27, 2007, 08:53:48 pm
Should the cable have any slack? My drips down between the carb and the adjuster. Has anybody heard of a transmission called 350C?
Title: Re: Shift points
Post by: VileZambonie on December 27, 2007, 10:46:25 pm
A 350C has a lockup torque converter.

If your shift points are on don't worry about the slack in the cable.
Title: Re: Shift points
Post by: jonkmbll89 on December 28, 2007, 06:22:20 pm
A 350C has a lockup torque converter.

If your shift points are on don't worry about the slack in the cable.

Is the 350C any good?
Title: Re: Shift points
Post by: VileZambonie on December 28, 2007, 09:34:24 pm
It's the same as a TH350 just has the lock up feature. Is it good? Not by today's standards but for a 3 speed automatic they're pretty reliable.
Title: Re: Shift points
Post by: Bowtie Bomber on December 31, 2007, 05:22:54 pm
I'm having a similar problem as well. I have a 780 CFM Holley and when I try to adjust the tranny cable (or plunger, w/e) it slips when I step on the throttle and also when I let off. And my truck shift at around 5k. And it scars the living heck out of me. I'd like it to shift right at 4k or even 3.5k for gas mileage purposes.

And just to make sure, does the vacuum from the tranny go to the T plug on theback of the intake manifold with vaccum ports in the back? I want to know if it needs constant vacuum.
Title: Re: Shift points
Post by: VileZambonie on December 31, 2007, 07:23:13 pm
Your vacuum modulator needs manifold vacuum. If your trans slips between shifts it's time for a rebuild
Title: Re: Shift points
Post by: 76_Scottsdale on January 02, 2008, 01:07:58 am
Bowtie your tranny does need constant manifold vacuum. I'm assuming you have TH350, but if it's slipping it has nothing to do with your kickdown cable, that just engages the passing gear with aggressive throttling. Like Vile said if it's slipping, might be time for a rebuild.