700r4 - The 1947 - Present Chevrolet & GMC Truck Message Board Network

71402BB · 09-01-2002, 04:25 PM

I maybe able to trade my Holly 650 D/P for a 700r4 (core). As far as I know they are all (he has 3 or 4 of them) early 80's 700r4's. I know these are not the preferd ones, but they can be updated wit the newer guts right? I belive these all came out of sation wagon's. Is there anything else I need to know about these tranny's? Anything else that I'm going to need besides the tranny it's self when swapping it into the burb? Thanks for any help! -Brian

red71cheyenne · 09-01-2002, 05:00 PM

Any core before 87 is going to need some new parts. Even the ones after will require some updating. You shouldn't have any trouble though, its a fairly straight across swap. Do you have an auto tranny now? You use the same cross member, just move it back to the th400 bolt holes. You'll have to drill 2 new holes for it too. The shock mount uses metric threads, so you'll have to get new bolts for that, but other than widening the holes in the cross member where the mount goes its fairly easy. Try to decide now how you are locking up the converter. I tried it both ways. Electrically you need to run a wire from the tranny to the TCS connection on the fuse box through the brake switch(new brake switch). Hydraulically you can have your tranny guy block the lock up solenoid and set it to automatically lock at 35-40 mph. Thats the way I am running mine now and I like it better. Any other questions, and I'll try to help. Jeff.

bigvinnie · 09-01-2002, 05:02 PM

make sure you get the tv cable and bracket.... if you're swapping to a truck that has a manual trans, you'll need cooler lines and either a trans cooler or a radiator with cooler built in, as well as an auto column and shifter linkage... you'll also need the lockup converter wiring, jegs or summit sells kits....

71402BB · 09-01-2002, 07:40 PM

Cool thanks for the help guys! 71redcheyenne what do you mena when you say any core before 87 will need updating and new parts..... what exactlly do you mean? Where would I get these parts? Summit, jegs? 71redcheyenne how do you like your tuned port injection? Does anybody else have any thing to add?

Longhorn Man · 09-01-2002, 08:23 PM

Read this link... http://www.chevytalk.org/forums/Foru...ML/000737.html

red71cheyenne · 09-01-2002, 08:57 PM

Pre 87 tranny's had weaker input drums, and output drums, weaker pumps and smaller clutch packs. It costs a lot to upgrade them, but its worth it in the end. I don't know where you would actually get the parts to do it yourself. When they rebuilt mine for the second time, the guy doing it knew what to do. As for the tune port, I love that thing. It looks great, runs great and has great throttle response. The only thing I don't like is it did not help my gas mileage like I thought it would. I still only get 14 at best. Even with the 700r4. Thinking about putting a 3.08 rear in to help. Jeff.

Longhorn Man · 09-01-2002, 09:08 PM

a 3.07 rear gear will probably hurt your gas mileage. You need to keep your engine at an efficent RPM, with the wind resistance our rigs have, and the weight they are, your engine would bog excesivly at real low RPM's tryin to keep up speed.
Low RPMs don't always mean high MPG.

red71cheyenne · 09-01-2002, 09:10 PM

Any other ideas then? I can't figure it out. The firebird that the tpi came out of got like 28 mpg. My 3.73 rear can't be causing that much drag can it? I don't know where else to go except the rear end. At 65mph I am running 2000 rpm even. Jeff.

gabet40 · 09-01-2002, 10:07 PM

ive got my torque converter lockup on a manual switch on my dash and love it cuz i can still get some nice power if i need to in 3rd gear.
im runnin an accel digital fuel injection system that actually has an extra wire harness that connects to the lockup harness and locks it up when it hits 4th gear and above a certain rpm that i can setadjust. then when i throttle down past a certain throttle % that i set/adjust, the computer senses it and automatically disengages the lock up and doesnt lock it back up until ive been cruising for at least 5 seconds with my throttle of course under the unlock %. but that another $80 that i dont have yet so, anyway.

red71- is there a way that you can get into the injection system and see what air/fuel ratio youre injecting? and possibly adjust it? it might be rich and wasting gas that for some reason it wasnt with your firebird

long horn- im runnin 3.08s and when i have my taller stock wheels on, im cruisin at 65 @ 15-1600 rpm, youre sayin that might actually hurt my mileage? how? when i have my shorter chomies on, im at about 2000 rpm @ 65 so im sure im fine there

Longhorn Man · 09-02-2002, 12:39 AM

I'm saying maybe...there are very few definates on this.
If your engine is not making much torque at X rpm, and that rpm is your cruise speed, it might not be making enough torque to overcome the weight and the wind resistance that your truck has at that speed.
A Fire bird weighs about 1000 pounds les than a small block automatic short bed, and is quite a bit more aerodynamic. So it only needs X amount of power to maintain cruise RPM. If you are trying to use that exact torque level, in a heavier vehicle, with more air smacking more frontal area, which is holding it back, you will have to tip in the throttle a little more to hold that speed.
As far as what gear, onless you have good programs, or way too much knowledge (any engeners in the house?) then it is a hit and miss game...trial and error.
Case in point.
My 350's power band is in the higher RPMs due to a lumpy cam. It doesn't get peppy untill you hit 3000 RPM or so.
In the GMC with 3.07 rear gears, I spin about 2500 RPM doing 60 MPH.
It gets consistant 9 - 11 MPG on the freeway.
SAME ENGINE...untouched, in my old truck, (heavier 3/4 ton longhorn) with 4.11 gears, 60 MPH was at about 3200 RPM.
Would get consistant 13-15 MPG.
Low RPMs does not ALWAYS mean high MPG.

red71cheyenne · 09-02-2002, 03:21 AM

I don't know. I have a buddy that just got a chip programmer and he is going to try and burn me a new chip with better fuel/air and injector pulse. He'll have to pull the bin files off of this chip to start with and see if he can tweak it. I'll let you know what I find out. As far as torque, I don't think I'd have any probs with the 3.07, but I don't know for sure. The tv cable is set good and I can get part throttle shifts and down shifts at will, so if that works now, I don't know that that would change anything. You may be right longhorn that aerodynamics are a factor. I just know for sure that on my old 70, with a stock 350, holley economizer, and granny 4 speed, I got 16 mpg all the time. Sure wish I still had that truck. Thanks, Jeff.

09-01-2002, 04:25 PM	#1
71402BB now thats a true COON DOG Join Date: Nov 2000 Location: Franconia, NH Posts: 1,977	700r4 I maybe able to trade my Holly 650 D/P for a 700r4 (core). As far as I know they are all (he has 3 or 4 of them) early 80's 700r4's. I know these are not the preferd ones, but they can be updated wit the newer guts right? I belive these all came out of sation wagon's. Is there anything else I need to know about these tranny's? Anything else that I'm going to need besides the tranny it's self when swapping it into the burb? Thanks for any help! -Brian __________________ current project 67 402BB stout th350 3.08's with a locker. Plan on tubs 18.5's out back! (thanks Burnsman!) 71 SWB Stepside, was a 250, now is a 402 Big Block with 4 speed and 3.73's ( was crushed by a tree, bed sold, motor pulled) was my first truck!... oh well... 72 LWB 4x4 350 4-speed 3.08's posi wearing army olive drab green (SOLD!) 68 BURB 50TH LOOKALIKE work in progress, soon to have 250-I6 with a 3-speed on the tree 4.11's and posi ( currently sitting in back yard tarped awaiting time, $$$, and lots of love!) 67 1 TON- work truck 396 sm 420 4-speed, flat bed 4.57 gears "big red" (my first landscape truck, very rusty and crusty! but still gets the job done when needed!)

09-01-2002, 05:00 PM	#2
red71cheyenne Back in the sticks Join Date: Jan 2001 Location: Fordland, MO Posts: 3,188	Any core before 87 is going to need some new parts. Even the ones after will require some updating. You shouldn't have any trouble though, its a fairly straight across swap. Do you have an auto tranny now? You use the same cross member, just move it back to the th400 bolt holes. You'll have to drill 2 new holes for it too. The shock mount uses metric threads, so you'll have to get new bolts for that, but other than widening the holes in the cross member where the mount goes its fairly easy. Try to decide now how you are locking up the converter. I tried it both ways. Electrically you need to run a wire from the tranny to the TCS connection on the fuse box through the brake switch(new brake switch). Hydraulically you can have your tranny guy block the lock up solenoid and set it to automatically lock at 35-40 mph. Thats the way I am running mine now and I like it better. Any other questions, and I'll try to help. Jeff. __________________ 1971 Cheyenne C-10 w/700R4 and Tuned Port Injection 1969 K5 Blazer w/Tuned Port 2010 2SS/RS Flaming Orange Camaro 2011 K1500 Suburban 2014 K1500 Pickup 2008 Nissan Altima? The wifes' hoopty

09-01-2002, 05:02 PM	#3
bigvinnie Registered User Join Date: Aug 2001 Location: escondido, ca 92026 Posts: 1,222	make sure you get the tv cable and bracket.... if you're swapping to a truck that has a manual trans, you'll need cooler lines and either a trans cooler or a radiator with cooler built in, as well as an auto column and shifter linkage... you'll also need the lockup converter wiring, jegs or summit sells kits.... __________________ '72 short step, 350, 700R4, tilt, ps, pdb, a/c, lowered coils, etc., other work in progress... San Diego, CA 72 Stepside Project

09-01-2002, 07:40 PM	#4
71402BB now thats a true COON DOG Join Date: Nov 2000 Location: Franconia, NH Posts: 1,977	Cool thanks for the help guys! 71redcheyenne what do you mena when you say any core before 87 will need updating and new parts..... what exactlly do you mean? Where would I get these parts? Summit, jegs? 71redcheyenne how do you like your tuned port injection? Does anybody else have any thing to add? __________________ current project 67 402BB stout th350 3.08's with a locker. Plan on tubs 18.5's out back! (thanks Burnsman!) 71 SWB Stepside, was a 250, now is a 402 Big Block with 4 speed and 3.73's ( was crushed by a tree, bed sold, motor pulled) was my first truck!... oh well... 72 LWB 4x4 350 4-speed 3.08's posi wearing army olive drab green (SOLD!) 68 BURB 50TH LOOKALIKE work in progress, soon to have 250-I6 with a 3-speed on the tree 4.11's and posi ( currently sitting in back yard tarped awaiting time, $$$, and lots of love!) 67 1 TON- work truck 396 sm 420 4-speed, flat bed 4.57 gears "big red" (my first landscape truck, very rusty and crusty! but still gets the job done when needed!)

09-01-2002, 08:57 PM	#6
red71cheyenne Back in the sticks Join Date: Jan 2001 Location: Fordland, MO Posts: 3,188	Pre 87 tranny's had weaker input drums, and output drums, weaker pumps and smaller clutch packs. It costs a lot to upgrade them, but its worth it in the end. I don't know where you would actually get the parts to do it yourself. When they rebuilt mine for the second time, the guy doing it knew what to do. As for the tune port, I love that thing. It looks great, runs great and has great throttle response. The only thing I don't like is it did not help my gas mileage like I thought it would. I still only get 14 at best. Even with the 700r4. Thinking about putting a 3.08 rear in to help. Jeff. __________________ 1971 Cheyenne C-10 w/700R4 and Tuned Port Injection 1969 K5 Blazer w/Tuned Port 2010 2SS/RS Flaming Orange Camaro 2011 K1500 Suburban 2014 K1500 Pickup 2008 Nissan Altima? The wifes' hoopty

09-01-2002, 08:23 PM	#5
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	Read this link... http://www.chevytalk.org/forums/Foru...ML/000737.html

09-01-2002, 09:08 PM	#7
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	a 3.07 rear gear will probably hurt your gas mileage. You need to keep your engine at an efficent RPM, with the wind resistance our rigs have, and the weight they are, your engine would bog excesivly at real low RPM's tryin to keep up speed. Low RPMs don't always mean high MPG.

09-01-2002, 09:10 PM	#8
red71cheyenne Back in the sticks Join Date: Jan 2001 Location: Fordland, MO Posts: 3,188	Any other ideas then? I can't figure it out. The firebird that the tpi came out of got like 28 mpg. My 3.73 rear can't be causing that much drag can it? I don't know where else to go except the rear end. At 65mph I am running 2000 rpm even. Jeff. __________________ 1971 Cheyenne C-10 w/700R4 and Tuned Port Injection 1969 K5 Blazer w/Tuned Port 2010 2SS/RS Flaming Orange Camaro 2011 K1500 Suburban 2014 K1500 Pickup 2008 Nissan Altima? The wifes' hoopty

09-01-2002, 10:07 PM	#9
gabet40 Registered User Join Date: Dec 1999 Location: Modesto, CA Posts: 565	ive got my torque converter lockup on a manual switch on my dash and love it cuz i can still get some nice power if i need to in 3rd gear. im runnin an accel digital fuel injection system that actually has an extra wire harness that connects to the lockup harness and locks it up when it hits 4th gear and above a certain rpm that i can setadjust. then when i throttle down past a certain throttle % that i set/adjust, the computer senses it and automatically disengages the lock up and doesnt lock it back up until ive been cruising for at least 5 seconds with my throttle of course under the unlock %. but that another $80 that i dont have yet so, anyway. red71- is there a way that you can get into the injection system and see what air/fuel ratio youre injecting? and possibly adjust it? it might be rich and wasting gas that for some reason it wasnt with your firebird long horn- im runnin 3.08s and when i have my taller stock wheels on, im cruisin at 65 @ 15-1600 rpm, youre sayin that might actually hurt my mileage? how? when i have my shorter chomies on, im at about 2000 rpm @ 65 so im sure im fine there __________________ Current owner of 2016 2500 Silverado Midnight Edition. Former owner of: 69 1/2 ton, change from long/fleet to short/fleet, shaved door handles, shaved tailgate, 4/6 drop, power windows, 700r4 72 blazer, 350 with Holley Commander 950 DFI, crane energizer cam, 350 tranny, dual sanderson blockhuggers/magnaflow exhaust

09-02-2002, 12:39 AM	#10
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	I'm saying maybe...there are very few definates on this. If your engine is not making much torque at X rpm, and that rpm is your cruise speed, it might not be making enough torque to overcome the weight and the wind resistance that your truck has at that speed. A Fire bird weighs about 1000 pounds les than a small block automatic short bed, and is quite a bit more aerodynamic. So it only needs X amount of power to maintain cruise RPM. If you are trying to use that exact torque level, in a heavier vehicle, with more air smacking more frontal area, which is holding it back, you will have to tip in the throttle a little more to hold that speed. As far as what gear, onless you have good programs, or way too much knowledge (any engeners in the house?) then it is a hit and miss game...trial and error. Case in point. My 350's power band is in the higher RPMs due to a lumpy cam. It doesn't get peppy untill you hit 3000 RPM or so. In the GMC with 3.07 rear gears, I spin about 2500 RPM doing 60 MPH. It gets consistant 9 - 11 MPG on the freeway. SAME ENGINE...untouched, in my old truck, (heavier 3/4 ton longhorn) with 4.11 gears, 60 MPH was at about 3200 RPM. Would get consistant 13-15 MPG. Low RPMs does not ALWAYS mean high MPG.

09-02-2002, 03:21 AM	#11
red71cheyenne Back in the sticks Join Date: Jan 2001 Location: Fordland, MO Posts: 3,188	I don't know. I have a buddy that just got a chip programmer and he is going to try and burn me a new chip with better fuel/air and injector pulse. He'll have to pull the bin files off of this chip to start with and see if he can tweak it. I'll let you know what I find out. As far as torque, I don't think I'd have any probs with the 3.07, but I don't know for sure. The tv cable is set good and I can get part throttle shifts and down shifts at will, so if that works now, I don't know that that would change anything. You may be right longhorn that aerodynamics are a factor. I just know for sure that on my old 70, with a stock 350, holley economizer, and granny 4 speed, I got 16 mpg all the time. Sure wish I still had that truck. Thanks, Jeff. __________________ 1971 Cheyenne C-10 w/700R4 and Tuned Port Injection 1969 K5 Blazer w/Tuned Port 2010 2SS/RS Flaming Orange Camaro 2011 K1500 Suburban 2014 K1500 Pickup 2008 Nissan Altima? The wifes' hoopty



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