Author Topic: Some silly Q's  (Read 16728 times)

Offline fitz

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Re: Some silly Q's
« Reply #15 on: January 19, 2010, 05:24:03 pm »
Fitz- I read on the internet that it's bad for the tranny if you downshift? Like 3rd at 55mph it's bad to drop into 2nd. Like you have to come to a complete stop and then put her in 1st. That true?

I drop mine into second all the time from 55mph, the factory kick down (passing gear) would do it on it's own on a stock vehicle so doing it manually will not hurt it.
It's not a good idear to downshift the tranny into 1st while moving.

Offline Layne

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Re: Some silly Q's
« Reply #16 on: January 19, 2010, 05:28:02 pm »
Ok thanks for the clarification.
77 c-10 - 77 400 86 700r4 "Emmy"
83 citation - 2.5L Four on the Floor!
88 sierra - reman 350 700r4 "Eleanor"
All normal practicality and rational money handling goes out of the window when it comes to my truck.

Offline campcrf

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Re: Some silly Q's
« Reply #17 on: January 19, 2010, 10:47:40 pm »
thats wierd ...  when I downshift mine it doesnt do anything...  (ati turbo 350) ... probably just the way they made it... I am not too familiar with the rmvb till i bought mine... takes a little to get used to.
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Offline fitz

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Re: Some silly Q's
« Reply #18 on: January 19, 2010, 11:05:04 pm »
thats wierd ...  when I downshift mine it doesnt do anything...  (ati turbo 350) ... probably just the way they made it... I am not too familiar with the rmvb till i bought mine... takes a little to get used to.

What do you use for a passing gear if it doesn't downshift?

Offline HAULIN IT

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Re: Some silly Q's
« Reply #19 on: January 19, 2010, 11:15:33 pm »
I feel with some digging we would find the 400 was used a few years in our trucks...'75-'77 is my guess.
 Wasn't there 2wd Suburbans with 400's in about those years? Lorne

Offline Grover 1

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Re: Some silly Q's
« Reply #20 on: January 20, 2010, 12:37:21 am »
I had heard the GM had problems with the small block 400 having overheating problems, trying to get too many cubic inches out of the small block that's why the short production.  any truth?
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Offline Irish_Alley

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Re: Some silly Q's
« Reply #21 on: January 20, 2010, 02:11:42 am »

Fitz- I read on the internet that it's bad for the tranny if you downshift? Like 3rd at 55mph it's bad to drop into 2nd. Like you have to come to a complete stop and then put her in 1st. That true?
Like fitz said when your tranny kicks into passing gear you drop down to the next gear down, in my 79 thats how i stop all the time but its also a stick when i had my 86 up and going with 5" tips comming out at 45's right before the rear tires i also would down shift just to hear her pop. from what I've heard its bad to up sift causing the tranny to "red line" if you will causing too much pressure inside and not to mention shifting at higher rpms will hurt the tranny unless it was built for that.
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Offline SUX2BU99

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Re: Some silly Q's
« Reply #22 on: January 20, 2010, 10:27:08 am »
I drove an 82 C10 with a 383 and TH350 with RMVB recently and if you didn't drop the shifter back down into First, it would start out in whatever gear the selector was in. If it was Drive, you would be starting out in 3rd. That was my first time driving a vehicle with an RVMB but I found it somewhat annoying but I'm sure a person would get used to it.

What's the advantage of it? I know it's more 'hardcore' to have it that way, but does it reduce breakable parts in the trans or something?

As far as auto tranny downshifting goes, I will downshift from 3rd to 2nd sometimes but quite often will take a vehicle out of overdrive into 3rd when driving around in town and not think twice about it. Dropping into 1st through I know is bad. I was told that it had something to do with the 1-way clutch sprag trying to rotate the other way when dropping into 1st. I don't know enough yet about auto trannies to know if that makes sense or not.
85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline Captkaos

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Re: Some silly Q's
« Reply #23 on: January 20, 2010, 06:13:27 pm »
Forgot to post this.  400's were used from 75-77 in pickups from all my info.

Offline VileZambonie

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Re: Some silly Q's
« Reply #24 on: January 20, 2010, 06:22:48 pm »
3-1 downshifts can occur automatically
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Offline fitz

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Re: Some silly Q's
« Reply #25 on: January 20, 2010, 07:41:41 pm »
3-1 downshifts can occur automatically

Thats how mine is set up.
Mine is not the reverse manual valve body, it still has the regular shift pattern (P,R,N,3,2,1). I always felt this was safer because in the event of a misshap (stuck throttle or ujoint failure) you can easily shift in to neutral.With a reverse manual valve body(P,R,N,1,2,3) if the throttle stuck open at the end of a run in 3rd gear you would have to shift into 2nd in 1st to get into neutral.
The manual valve body's do take some getting used to. When I first bought this car my plans were to put a 5 or 6 speed in it. The overdrive would take the curse off of the 4.10's. I priced it out and stopped counting when the parts bill added up to over $5K to do it right with all new stuff.
I quickly learned to love this tranny thats in the car. It's made a good number of passes down the 1/4 mile and has yet to give me any problems.

Offline Layne

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Re: Some silly Q's
« Reply #26 on: January 21, 2010, 01:42:52 pm »
I had heard the GM had problems with the small block 400 having overheating problems, trying to get too many cubic inches out of the small block that's why the short production.  any truth?
I've heard that too. I think because of the siamese cylinders.
77 c-10 - 77 400 86 700r4 "Emmy"
83 citation - 2.5L Four on the Floor!
88 sierra - reman 350 700r4 "Eleanor"
All normal practicality and rational money handling goes out of the window when it comes to my truck.

Offline campcrf

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Re: Some silly Q's
« Reply #27 on: January 21, 2010, 06:57:35 pm »
Fitz... i guess it does shift down.. but not automaticaly... dont notice till i hammer on it, then its in second... if that makes sence.
-smile-... Just because its contageous

Offline team39763

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Re: Some silly Q's
« Reply #28 on: January 21, 2010, 09:41:07 pm »
I'm not real sure what the advantages are of a RMVB.  A fellow racer down here told me that it's a more natural motion to pull the shift lever backwards rather than push it forward.  I also read that most manual valvebodies will give you nice firm shift aswell as get rid of the kickdown cable.  All those reasons were what convinced me to get the RMVB.

Offline SUX2BU99

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Re: Some silly Q's
« Reply #29 on: January 22, 2010, 10:27:00 am »
Forgot to post this.  400's were used from 75-77 in pickups from all my info.

Not that I'm convinced in it's accuracy but my Haynes manual says the 400 with engine code U was in 75-76 4x4's and the 400 with engine code R was in 77-79 or 80.
85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.