Shift Points

N

NOWAY55

New member
Well for some reason, it just hit me that my shift points aren't doing me any good with the new engine build. (see below)

What do I need to do to get the points raised a bit to make more use of the power?

Cost?

If someone close enough to me could do this, I would drive it to them!
 
sycho

sycho

New member
Re: Shift Points

with that build and cam, youll probably want it to shift around 5200. you can buy shift governors for the 700 right thru gm for not that much$. easy to install also. dont have any part #'s for you maybe someone else can jump on.
 
Tooky

Tooky

Serious about performance
Re: Shift Points

You could try to find a "Corvette" 700R4 governor known to shift near 5000-5200. The 700R4 is a lot like a big honking carburetor... All controlled by little springs and valves and hydraulic pressure. Calibrating one is like changing jets to meter fuel in a carb, but a lot worse.

The popular B&M/TCI/etc Governor Recalibration Kits are aimed at high revving N/A engines so even their heaviest weights/springs may not be heavy enough to give you the shift you need. I ended up making friends with a transmission shop and I wound up with a giant bag of like 12 700R4 governors so I could do my own trial and error mixing and matching the 2 springs, 2 heavy outer weights, and 2 inner weights that control the shift RPM.

Once you start changing the governor you also realize that it directly controls the PART-THROTTLE shift points too, and to really fine tune it you need to open up the valve body and start to calibrate the individual Shift Valve Springs as well as possibly the TV Valve Spring or the TV Valve itself. I could write a book on this stuff but I have a feeling there's only like 4 guys out there who'll go to the lengths I did to get mine close (and it still isn't right! I'm just sick of getting ATF in my face/hair/ears and it's close enough until I can get some time on a lift instead of jack stands..)

One more piece of advice: the governor shift RPM will change of course, between different transmission calibrations!! So if someone has a "built" trans (unknown calibration) with a governor that shifted at X RPM, that's no guarantee it will shift anywhere near that same RPM in YOUR transmission with YOUR calibration. (Unless you have a known calibration like a factory stock 1LHM Syclone 700R4).
 
JSM

JSM

Active member
Re: Shift Points

A few keystrokes and your done....o wait a 700r4......lots of tranny fluid in your eyes, ears, change springs 10x and you will find a compromise somewhere. Should be able to find a kit with several springs/weights not that expensive just time consuming.
 
N

NOWAY55

New member
Re: Shift Points

The 80 will be the way to go some day. Not in the budget right now. Still recovering from the rebuild, Rims and Alky !

Anyone close to Philly have any experience with changing springs / weights on the 700 ?
 
Brassmonkey

Brassmonkey

Cruzin' Mel Man
Re: Shift Points

I had the governor changed in my 4L60 and it is working great. The shift points are right in the power band. The tranny builder said he "got lucky" with the choice of wieghts. Remember this though, once you change the shift points using the governor, you will also change the shift points at all throttle positions and speeds. Mine does not shift into OD until over 52 mph now, which can be annoying in town.
 
Tooky

Tooky

Serious about performance
Re: Shift Points

Hey Mel, with that high of a 3-4 upshift, can you still get a proper 3-4 WOT upshift around 95-100 MPH when you are drag racing the 1/4 mi?

--------------------------

Guys, here is the best page I have found about 700R4 governor calibration: http://www.iotech.no/corvette/projects/700r4-conversion Look about 3/4 down the page. He has photos of the governor and the springs/weights and a series of photos describing how it works.

And here is a great ThirdGen.org 700R4 F-Body post from a guy who experimented and made notes how his governor recalibration went: http://www.thirdgen.org/techboard/t...in/267954-700r4-governor-weights-springs.html
 
Brassmonkey

Brassmonkey

Cruzin' Mel Man
Re: Shift Points

I don't know what the 3-4 shifts are in the 1/4 mi., all I have raced since the upgrade is the 1/8th. That is where my Sy really shines any way, most can catch me in the 1/4, but very few can catch me in the 1/8th.

Tooky said:
Hey Mel, with that high of a 3-4 upshift, can you still get a proper 3-4 WOT upshift around 95-100 MPH when you are drag racing the 1/4 mi?
Click to expand...
 
sharkbait

sharkbait

New member
Re: Shift Points

i have a dumb question..........syty have floor shifters right? why don't you guys set the ship points lower, and manually shift the trucks out when you want to race?

i just had my 700r4 rebuilt with 16vaine pump, corvette survo blah blah blah. i set the TV cable to shift like 2K. it goes into 4th nice for around town driving. (saves gas?)
 
Brassmonkey

Brassmonkey

Cruzin' Mel Man
Re: Shift Points

I tried that and either over revved or shifted too early and I didn't feel like installing a shift light.

sharkbait said:
i have a dumb question..........syty have floor shifters right? why don't you guys set the ship points lower, and manually shift the trucks out when you want to race?

i just had my 700r4 rebuilt with 16vaine pump, corvette survo blah blah blah. i set the TV cable to shift like 2K. it goes into 4th nice for around town driving. (saves gas?)
Click to expand...
 
dgoodhue

dgoodhue

BuSTeD 4.3
Re: Shift Points

sharkbait said:
i have a dumb question..........syty have floor shifters right? why don't you guys set the ship points lower, and manually shift the trucks out when you want to race?

i just had my 700r4 rebuilt with 16vaine pump, corvette survo blah blah blah. i set the TV cable to shift like 2K. it goes into 4th nice for around town driving. (saves gas?)
Click to expand...

First gear in a stock Syclone during a boosted launch lasts only 1 sec. Add in some mods and the time needed for anything close to a consistent shift point is near impossible.
 
George Blake

George Blake

DONATING MEMBER
Re: Shift Points

Don't use the TV cable to set shift points. Sounds like you lowered your line pressures. Not good on a 700r4.

sharkbait said:
i have a dumb question..........syty have floor shifters right? why don't you guys set the ship points lower, and manually shift the trucks out when you want to race?

i just had my 700r4 rebuilt with 16vaine pump, corvette survo blah blah blah. i set the TV cable to shift like 2K. it goes into 4th nice for around town driving. (saves gas?)
Click to expand...
 
gkrcr882

gkrcr882

SyTyless......for now!
Re: Shift Points

I have a similar problem, I fear that someone changed the governor in my trans, and it has higher than normal shift points. I'm aiming for a 4600-4800 WOT shift so I dont have to back off to prevent overreving. Am I looking for lighter weights or heavier ones, along with the springs?
 
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