|12-02-2011 06:35 AM|
|sbc307||but i still think the trans should be gone over this winter and replace the converter because he had the trans and converter like this for awhile and he also didnt install a external trans cooler he used the factory one... so now i think that hurt the trans with all that heat from the factory cooler and the converter always in stall mode........... im going to have the trans out anyway when i have the engine out so i think it will be worth the time to go over it again and ill be doing it so then ill know what i have............. plus the trans wasnt shifting right since i got it so could have damage done from that.............|
|12-02-2011 06:26 AM|
|12-02-2011 06:22 AM|
|sbc307||factory tach is broke, im gonna be putting a autometer in, i know there not very accurate, so i dont know the exact rpms, when i said 3500 above i was just making a point, but from the way it sounds the motor is spinng pretty close to that all the time..... and i know im not doing 99mph lol id give u wat i think im reading which prolly be around 65 but the speedo cable is broke also, so i dont even know.......... alot of little things need to be done to this car..... thanks for the info guys...|
|12-02-2011 06:16 AM|
the geometry corrector will help to a degree but, more than likely with the rear gearing and the cam installed, it has changed the power curve and hence the early shifts. a governor recalibration kit can fix that. the only thing is, it may be best to wait till after you do the gear swap as it may actually get better with the gear change.
as always though, the cable needs to be completely tight at WOT or it will not shift properly.
the 3-4 shift on a 700 is typically soft to begin with and usually doesnt have much if any shift "feel" when it makes the 3-4 shift without some sort of kit or modification to the 3-4 circuit.
as far as the converter goes, id leave it in as well as it will work better with the cam than a stock converter will. it may be a hair bit too much stall but, for the thought of maybe a weekend blast here and there at the local track if you go, it will definitely help with the cars overall performance, especially the launch and 60 ft times.
|12-01-2011 10:23 PM|
If you are switching carbs get the correct TV & TV corrector Brackets.
With the Edelbrock linkage the TV pressure rise will be Low= BAD and can burn the Trans up. Your TV Cable Bracket may be Ok with the Edelbrock.
Eddy >> http://www.summitracing.com/parts/SUM-700203/
Holley >> http://www.summitracing.com/parts/SUM-700202/
You should do a Pressure test.
Are you using the Factory Tach? If so they are famous for incorrect readings.
With 2.73 gear, 26" tall Tire, 3500rpm you should be running 99mph. in 3rd gear in 4th 141mph. In 2nd gear 61mph.
|12-01-2011 01:48 PM|
|sbc307||this is starting to make sense now, the gears in the back are 2.73's factory highway gears with a factory posi, over the winter im switching it too 4.10 or 3.73 with a locker cause the posi stopped working, (too many burnouts from the previous owner) and i want better gearing. 1st to 2nd shift feels pretty good, nice spacing, 2nd to 3rd seems alittle quick some rpm change, and 4th/O.D is barely noticible. i took the car back out and it does go into 4th but i didnt even notice it..... Right now its got an edelbrock carb on it, with the factory gm kick down cable, with the factory kickdown bracket....... over the winter im doing motor work to it and it will be switched to a holley carb. Rear tires are 235/60/R15 on stock Z28 rims. Also this guy did everthing alttle backwards the engine is a 355 with a towing cam in it, which calls for a stock converter not this nice 2800 stall one...... he told me he was going to redo it heads up with a bigger cam in it, but money got tight and he had to sell it.......... so this winter im redoing the engine abd possibly the trans. So theres the whole scoop on the car...........|
|12-01-2011 06:29 AM|
also, like ssedan asked, whats the rear gear ratio and tire size as it also play a role in what the rpm will be with lockup engaged.
|12-01-2011 03:17 AM|
The above Info is correct, only the TCC Lockup needs power to work.
I just assumed you were calling the Lockup, OD/4th gear as some do.
It does sound like you may have a 2-4 Band or 2-4 Servo problem. You stated very fast 2-3 shift, now no OD/4th gear. 2nd & 4th gear use the same Band.
Converting it to a Carb requires the correct TV Cable Bracket and TV geometry corrector Bracket, if using an Aftermarket Carb such as Holley, Demon or Edelbrock for proper Line pressure rise. Correct TV cable setting is very important to prevent Trans damage.
What Rear gear ratio and Tire size do you have?
|11-30-2011 06:59 PM|
|sbc307||so if i have 4 forward gears hense the trans is in forth and im cruising 60mph in 4th why am i still spinning around 3500rpm in stead of like 2000rpm like if my trans was in O.D. so im assumming the trans is in 4th but my converter is basically free floating..... correct? and locking the converter locks the TCC and drops my rpms...... correct? sorry this is all new too me, i have no clue exactly wat everything does all the guy told me when i bought that i need to run a hot wire to the trans to get 4th gear to work............. thanks for the info guys, im still learning lol|
|11-30-2011 06:52 PM|
As tnsmith said, the only electric control on the 700R4 (and the 4L60) is for converter lock-up. Early 700s should be locked in OD (4th) to prevent damage, but from 1985 (or maybe late 1985) on it is not necessary to lock the converter (although nice for better cruising gas mileage).
I have a 1992 4L60 (just a new name for the 700R4) in my rod and do not lock it in 4th, although I may wire in a switch to do that.
But do have the TV cable properly adjusted.
|11-30-2011 06:03 PM|
the converter clutch can be omitted and the trans will have all 4 forward gears without a single wire hooked up to that trans if it is internally in proper working order.
the ventura you see in my avitar has a 700R4 that i built and purposely built without the use of the converter clutch operation and it has all 4 forward gears and no electrical hooked up. all i wanted was a hydraulic 4 speed which is what the 700R4 is.
|11-30-2011 05:26 PM|
700r4 trans did have a computer it told the trans when to shift into overdrive, the first 3 gears are mechcanical, if you click on the hughs perfomance link above and it shows the 4 prong plug, and i believe prong D says it from the ECM which tells the trans when to use overdrive................ so you can use a 700r4 with out a computer but if its a lock up converter style the converter wont lock in, unless you rewire it which is what im doing and thats why overdrive dont work.
|11-30-2011 05:15 PM|
700R4 did not use a computer shift until 1993 (when it was called the 4L60E).
Good info on the 700R4 TV cable set-up here
|11-30-2011 04:14 PM|
|pricesgarages||the no computer will not cause no overdrive did you get the correct throttle linkage for the carb its called a throttle cable geomerty corrector and correct brackets for it|
|11-30-2011 03:49 PM|
|sbc307||So all i have todo is run a positive wire to a switch then to the A terminal and just flip the switch whenever i want overdrive to kick in.... correct? No ground needed.... or do i need a ground on terminal D too? I also think i might be a servo problem because 1st to 2nd seems good, deff not too close. im probably pulling the trans out this winter and imma go over it, because i dont know whats done and whats not..................|
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