73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: Layne on January 18, 2010, 09:51:49 pm
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Does anybody know why GM never had the 400 engine in the 2wd C-10's? Secondly, this has been bothering me for a while, and I don't want to sound dumb, but if you have a manual valve body on your trans, does it act like a manual if you take off in third? Like 3rd gear stick = 3rd gear turbo 350.
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Yes, if you stick your trans in third, it should take off in third(if you have a manual valvebody). I asked about that when I was doing research on the proper way to do a burnout with a RMVB. They said start in 2nd. Also, I'd heard of guys with a TH400 taking off in 2nd...I'm think to kill some of the gear ratio or something like that.
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Would that superheat the T/C; kinda like smoking the clutch?
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I think that was also mentioned when I asked about it.
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Team... your right.. i just put a rmvb in mine last year..... fun to drive... ;D
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I'd guess if anyone were to steal your truck, it'd be a dog starting in 3rd ::)
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Anybody know about the 400 though?
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400's were only optional on the K10/20 in 1975, the next year they was the last. No idea on why.
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Hmm. Maybe that motor that guy sold me didn't come out of a 77 K30. I did check to make sure it was a 400 though.
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I don't want to sound dumb, but if you have a manual valve body on your trans, does it act like a manual if you take off in third? Like 3rd gear stick = 3rd gear turbo 350.
I've got a Turbo 350 manual valve body from Fairbanks transmission in my 69 camaro.
I've tried what your asking and this is how mine works.
If from a stand still you place the shifter in 3rd and start moving my tranny is still in 1st gear. Now your in the odd position of driving with the shifter in 3rd but the trannys in first, so now to shift to second you have to pull the shifter back down into 1st that back up into second.
Maybe not all manual valve bodys are the same but in my car no matter where you place the shifter it will always start off in first gear. Theres no way you can start my car in 2nd or 3rd gear.
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I had a customer with a C10 with a 400 in it he swore was factory (76 I think) but he coulda been full of it. My 80 C10 had a 400 but that was a replacement from the 350 Diesel.
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I went here- http://brochures.slosh.com/ from the post Weird Option Code and rigged up my truck. Then I looked at motor options and all they (GM) had was 400's in the K series. I just thought it was odd it was a 4 wheeler only deal.
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 have a 77 LWB C10 with the F44 if anyone was to look it up in the last pic.
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Maybe it was 77 for the last year now that I think about it, I will have to check. I don't think it was ever offered in 2WD though.
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Well from 81-86 you could only get a 350 in 4x4, 4x2's could only get a 305.
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Well from 81-86 you could only get a 350 in 4x4, 4x2's could only get a 305.
Never knew that.
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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.
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Ok thanks for the clarification.
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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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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?
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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
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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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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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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.
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Forgot to post this. 400's were used from 75-77 in pickups from all my info.
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3-1 downshifts can occur automatically
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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.
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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.
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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.
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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.
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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.
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the later model 400's were only available in fullsize cars. The last year was 1980.
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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.
Any manual valve body will let you eliminate the kick down cable.
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Adding on, What is a Lenco? Has anyone of you guys read the new Hot rod this month? They got a bad butt Fiero with super heated induction making 200 some odd horse with an.... iron duke!!!