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Suicide-D · 06-19-2002, 01:41 PM

How many rpm's should my truck be shifting at? My truck is shifting between 1800 and 2200 rpm's from 1st to 2nd and 2nd to 3rd. This just doesn't seem right to me. I just recently put this engine in and honestly never paid attention to where the other one shifted at. I didnt have a tach on it then either...Is the vacuum modulator the cause of this? Also is the vacuum modulator suppose to be on full vacuum or timed? It is on full vacuum right now. I dont want to shift this thing manually to build decent power.

Thanks

68 with 350 TPI · 06-19-2002, 01:45 PM

You can make it shift higher and lower by adj. the modulator.

I think you may be shifting a little low but it depends on the gears in the truck also as to where the best spot is.

Frank_Zeller · 06-19-2002, 02:03 PM

Did you forget to hook up the kick down cable to the carb?

Is that WOT shift points are just cruzing?

Modulator get full vacumn from the mainfold.

Suicide-D · 06-19-2002, 02:24 PM

kick down is hooked up... was not hooked up on the last motor... that is just cruising, normal not getting on it ... but it still shifts early even when im in it if I recall... I'll check on that.

Suicide-D · 06-19-2002, 02:26 PM

well the vacuum is hooked up to a supposedly full vacuum port on my carb, not on the manifold.

Frank_Zeller · 06-19-2002, 02:59 PM

Make sure when your WOT (engine off) the kick down cable is all the way extended.

If thats not the problem then you can change springs in the governor. The governor is on the drivers side of trans underneath that tin cup look thing in front of the speedo cable. Stiffer springs make it shift sooner...weaker springs shift latter. This also effects your down shift pionts. B&M sells a kit you can buy thought summit racing.

Suicide-D · 06-19-2002, 03:04 PM

ok i'll check out the kick down cable... my buddy helping me hooked it up... I was responsible for anything that required going underneath....so I didnt supervise that operation. I have no idea where this tranny came from... my truck was a 6-cyl three speed on the column from the factory. When I got it it was a dog-tired 283 and turbo 350. I may have to change the springs.

hanssolo · 06-19-2002, 04:26 PM

Are stock modulators adjustable? I thought you had to get an aftermarket one.
Dobber- if I get back there I want to live in the Katy-Mason Rd. area.

Gordo · 06-19-2002, 04:48 PM

You want a direct vaccum from intake feeding the mod, and stock modulators are not adjustable. Frank is right on that cable adjustment, WOT and max tv cable length should match.

Suicide-D · 06-19-2002, 04:56 PM

yeah Katy is excellent and wonderful schools i hear... I live right off of Mason rd.

Suicide-D · 06-19-2002, 05:01 PM

The kickdown is set up correctly. I'll need to pick up a fitting to run the vacuum directly off the intake. to see if that changes anything. I want to replace the Carb on my truck anyway I just dont like it very much... Edelbrock 1405 600cfm junk... in my opinion..

Longhorn Man · 06-19-2002, 07:32 PM

Just so no one is mis lead, the cable is a kick down cable, not a TV cable. The Throttle Valve cable is only on overdrives.
Yes, the stock modulater is adjustable, I discovered this last weekend. Remove the hose and look inside of the hole, turn that little screw in (clockwise) to shift higher, loosen it to shift sooner.
Hooking it up to the intake will probably not affect it, and if it does, it'll shift sooner than it is now.

Suicide-D · 06-20-2002, 09:45 AM

Ok now I'm wondering if the kickdown is causing my problem... it is hooked up correctly as far as I can tell. The cable is at full extension at wide open throttle. What is the function of this cable? I dont feel my transmission down shift when I step on it while cruising in third gear. Could my modulator be set to shift so early it's taking the kickdown out? I haven't had a chance to crawl under it and tweek the modulator yet.

Thanks for all the advice.

Longhorn Man · 06-20-2002, 05:15 PM

No, modulater is not doing anything on the kick down. That is all on the kick down cable.
Sounds like the cable is not adjusted correcly. Disconnect it from the carb, and pull on the cable. Line it up to the throttle, where it was hooked up, and see if it was adjusted right. You want full cable extention at wide open throttle.

Suicide-D · 06-20-2002, 06:38 PM

Thanks Longhornmail & Frank_Zeller.... the kickdown WASN'T adjusted correctly. I took the cable lose and sure enough... it came out about an 1/4 of an inch... it didnt do that hooked up. I tightened it up and it kicks down now. I didnt mess with the modulator yet... I crawled under and the vacuum hose had clamps on it... so I'll mess with it tommorrow. It still shifts early.

Thanks again.

Longhorn Man · 06-20-2002, 07:18 PM

Good deal.
Under steady cruising, or light throttle, all the up shifts are handled my the vacume modulator.
Under WOT, the cable is pulled out, and basicly trying to kick it down, therefore holding it in the lowest gear it can.
This is where the govenor comes into play. The govenor will make it shift at a predetermined RPM. This way, if you are doing 80 MPH, and somehow, your shifter gets slammed into first, it will not go into first, some wouldn't even go into 2nd.
Matter of fact, you could place your shifter in first, and haul @ss, it WILL eventually go all the way up to 3rd gear, but you'll be taxing the pee outa your motor, and you'll be aproaching tripple digits when it finally shifts.
Of course, this is asuming the govenor is set at the right RPM, and still in working order.
I know it is on the wife's S-10 blazer, but that's another story.

06-19-2002, 01:41 PM	#1
Suicide-D Registered User Join Date: Jan 2001 Location: Katy, TX...but the love of my life resides in Dublin,OH. Posts: 1,408	turbo 350 How many rpm's should my truck be shifting at? My truck is shifting between 1800 and 2200 rpm's from 1st to 2nd and 2nd to 3rd. This just doesn't seem right to me. I just recently put this engine in and honestly never paid attention to where the other one shifted at. I didnt have a tach on it then either...Is the vacuum modulator the cause of this? Also is the vacuum modulator suppose to be on full vacuum or timed? It is on full vacuum right now. I dont want to shift this thing manually to build decent power. Thanks

06-19-2002, 01:45 PM	#2
68 with 350 TPI Registered User Join Date: May 2002 Location: Wingate NC Posts: 456	You can make it shift higher and lower by adj. the modulator. I think you may be shifting a little low but it depends on the gears in the truck also as to where the best spot is. __________________ Life is good with a 6-71 supercharged 355 in a 72 camaro

06-19-2002, 02:03 PM	#3
Frank_Zeller Registered User Join Date: Jun 2001 Location: Austin, Texas Posts: 796	Did you forget to hook up the kick down cable to the carb? Is that WOT shift points are just cruzing? Modulator get full vacumn from the mainfold. __________________ 69 SWB C/10 5-6 drop 700R4 69 Firebird Convert 455 4 spd 70 Torino GT Convert Austin-Texas

06-19-2002, 02:59 PM	#6
Frank_Zeller Registered User Join Date: Jun 2001 Location: Austin, Texas Posts: 796	Make sure when your WOT (engine off) the kick down cable is all the way extended. If thats not the problem then you can change springs in the governor. The governor is on the drivers side of trans underneath that tin cup look thing in front of the speedo cable. Stiffer springs make it shift sooner...weaker springs shift latter. This also effects your down shift pionts. B&M sells a kit you can buy thought summit racing. __________________ 69 SWB C/10 5-6 drop 700R4 69 Firebird Convert 455 4 spd 70 Torino GT Convert Austin-Texas Last edited by Frank_Zeller; 06-19-2002 at 03:03 PM.

06-19-2002, 04:26 PM	#8
hanssolo Registered User Join Date: Sep 2001 Location: central Ill. USA Posts: 447	Are stock modulators adjustable? I thought you had to get an aftermarket one. Dobber- if I get back there I want to live in the Katy-Mason Rd. area. __________________ 69 C10 longbed: 357c.i. /TH400/3.73s/AC/ beige primer/saving $ for paint ______________________________

06-19-2002, 02:24 PM	#4
Suicide-D Registered User Join Date: Jan 2001 Location: Katy, TX...but the love of my life resides in Dublin,OH. Posts: 1,408	kick down is hooked up... was not hooked up on the last motor... that is just cruising, normal not getting on it ... but it still shifts early even when im in it if I recall... I'll check on that.

06-19-2002, 02:26 PM	#5
Suicide-D Registered User Join Date: Jan 2001 Location: Katy, TX...but the love of my life resides in Dublin,OH. Posts: 1,408	well the vacuum is hooked up to a supposedly full vacuum port on my carb, not on the manifold.

06-19-2002, 03:04 PM	#7
Suicide-D Registered User Join Date: Jan 2001 Location: Katy, TX...but the love of my life resides in Dublin,OH. Posts: 1,408	ok i'll check out the kick down cable... my buddy helping me hooked it up... I was responsible for anything that required going underneath....so I didnt supervise that operation. I have no idea where this tranny came from... my truck was a 6-cyl three speed on the column from the factory. When I got it it was a dog-tired 283 and turbo 350. I may have to change the springs.

06-19-2002, 04:48 PM	#9
Gordo Registered User Join Date: Jan 2001 Location: Killingworth, CT. USA Posts: 3,378	You want a direct vaccum from intake feeding the mod, and stock modulators are not adjustable. Frank is right on that cable adjustment, WOT and max tv cable length should match. __________________ 1971 C10 swb stepside 350/700R4/3.73posi (retired as of 4/22/03) 1998 S10 short bed 2002 S10 Blazer 1942 Oldsmobile 1958 Massey Harris Pony 1951 Wife Killingworth, Connecticut May those who love us, love us, any of those who do not love us, may God turn their hearts. And if God is unable to turn their hearts, may he turn their ankles so we may know them by their limping. A man who works with his hands is a laborer; a man who works with his hands and his brain is a craftsman; but a man who works with his hands and his brain and his heart is an artist.

06-19-2002, 04:56 PM	#10
Suicide-D Registered User Join Date: Jan 2001 Location: Katy, TX...but the love of my life resides in Dublin,OH. Posts: 1,408	yeah Katy is excellent and wonderful schools i hear... I live right off of Mason rd.

06-19-2002, 05:01 PM	#11
Suicide-D Registered User Join Date: Jan 2001 Location: Katy, TX...but the love of my life resides in Dublin,OH. Posts: 1,408	The kickdown is set up correctly. I'll need to pick up a fitting to run the vacuum directly off the intake. to see if that changes anything. I want to replace the Carb on my truck anyway I just dont like it very much... Edelbrock 1405 600cfm junk... in my opinion..

06-19-2002, 07:32 PM	#12
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	Just so no one is mis lead, the cable is a kick down cable, not a TV cable. The Throttle Valve cable is only on overdrives. Yes, the stock modulater is adjustable, I discovered this last weekend. Remove the hose and look inside of the hole, turn that little screw in (clockwise) to shift higher, loosen it to shift sooner. Hooking it up to the intake will probably not affect it, and if it does, it'll shift sooner than it is now.

06-20-2002, 09:45 AM	#13
Suicide-D Registered User Join Date: Jan 2001 Location: Katy, TX...but the love of my life resides in Dublin,OH. Posts: 1,408	Ok now I'm wondering if the kickdown is causing my problem... it is hooked up correctly as far as I can tell. The cable is at full extension at wide open throttle. What is the function of this cable? I dont feel my transmission down shift when I step on it while cruising in third gear. Could my modulator be set to shift so early it's taking the kickdown out? I haven't had a chance to crawl under it and tweek the modulator yet. Thanks for all the advice.

06-20-2002, 05:15 PM	#14
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	No, modulater is not doing anything on the kick down. That is all on the kick down cable. Sounds like the cable is not adjusted correcly. Disconnect it from the carb, and pull on the cable. Line it up to the throttle, where it was hooked up, and see if it was adjusted right. You want full cable extention at wide open throttle.

06-20-2002, 06:38 PM	#15
Suicide-D Registered User Join Date: Jan 2001 Location: Katy, TX...but the love of my life resides in Dublin,OH. Posts: 1,408	Thanks Longhornmail & Frank_Zeller.... the kickdown WASN'T adjusted correctly. I took the cable lose and sure enough... it came out about an 1/4 of an inch... it didnt do that hooked up. I tightened it up and it kicks down now. I didnt mess with the modulator yet... I crawled under and the vacuum hose had clamps on it... so I'll mess with it tommorrow. It still shifts early. Thanks again.



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06-20-2002, 07:18 PM	#16
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	Good deal. Under steady cruising, or light throttle, all the up shifts are handled my the vacume modulator. Under WOT, the cable is pulled out, and basicly trying to kick it down, therefore holding it in the lowest gear it can. This is where the govenor comes into play. The govenor will make it shift at a predetermined RPM. This way, if you are doing 80 MPH, and somehow, your shifter gets slammed into first, it will not go into first, some wouldn't even go into 2nd. Matter of fact, you could place your shifter in first, and haul @ss, it WILL eventually go all the way up to 3rd gear, but you'll be taxing the pee outa your motor, and you'll be aproaching tripple digits when it finally shifts. Of course, this is asuming the govenor is set at the right RPM, and still in working order. I know it is on the wife's S-10 blazer, but that's another story.

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