I'm looking to install my 700R4 into my 1972 Chevy Blazer. I hear the 700 is longer than the turbo 350. If this is true wondering what to do with the cross member and how to make it all work any and all suggestions will be greatly appreciated.
CK5
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700R4
- Thread starter Montanachris
- Start date
Yes it is longer iirc 1.5". I just redrilled the frame where the new cross member ended up. You will need shortened drive shaft for rear and lengthened front.
Also you'll want to take in account the highway cruise rpm and engine power band
Also you'll want to take in account the highway cruise rpm and engine power band
Looks like I have some work cut out for me. When you say to account for hwy cruise rpm and power band what are you referring to exactly.
Let's just hit the highlights...Step one, check your account balance or credit card limit, Step two, you will need a custom output shaft installed in the 700R4 to mate up to the input on the transfer case, you can retain the 350 style adapter. Step three, install 700R4, relocate crossmember to new position and drill frame holes as needed, ruin three drill bits and narrowly avoid a visit to the ER because you were wearing your safety glasses. If you weren't wearing your safety glasses start again at step one. Shorten rear driveshaft and lengthen front driveshaft, original flexplate will work, most aftermarket dipsticks and tubes will clear, cooler lines can work with careful bending. Modify exhaust for new crossmember position. Step four, Re-check account balance and credit card limits, elongate hole in floor for transfer case shifter in its new position. Throw away your custom built console and drink holder, create patch from your new carpet set. Step 5, re-work transmission shift linkage as needed as well as carb linkage and brackets to support TV cable with proper geometry. Step six, install dual pole brake switch, ( Standard ignition part number SLS-110) and wiring for torque converter lockup, adjust tv cable as needed, ( tight as can possibly be at wide open throttle). Step seven, fill with fluid and check all adjustments, test drive and realize the 4th gear RPM is too low with your 3.73 gears and 35 inch tires to cruise at highway speeds. Check account balance and credit card limit and take wife shopping......
700R4 and NP205 answers !!!!!
I have for several months now been looking for a simple way of going from a Turbo 350 trans with NP205 TC to a 700R4 trans and the NP205 TC. Well the answer is simple. There is none. I purchased the 7Q35A that everyone seems to THINK :haha: will work. It want. Its to short. The Advanced...
ck5.com
Okay I appreciate your thoughts on this
Geez Jeff, suppose couple of those boys might be dead!700R4 and NP205 answers !!!!!
I have for several months now been looking for a simple way of going from a Turbo 350 trans with NP205 TC to a 700R4 trans and the NP205 TC. Well the answer is simple. There is none. I purchased the 7Q35A that everyone seems to THINK :haha: will work. It want. Its to short. The Advanced...
I did this on my '74 Nova. It’s cheaper when you already have the diff gearing setup (3.73, but on a car) and you don’t have to redo two driveshafts.
Yup Greg nailed it. I did all that. I skipped the carpet patch. Move the shift boot, just barely covered the larger hole. Later I made sheet metal screw on patch. Replace the 43 year old carpet last spring.
I didn't like the cruising in high gear. Truck was 4.10 gear =2.87 in over drive, and 33's . 55 mph was @1300, no power to pass, accelerate. My power band begins @2500. running 75 80 was great.
I switched to 4.88 3.41 in over drive. 55 is 2k and 65 is @2400ish.
I didn't like the cruising in high gear. Truck was 4.10 gear =2.87 in over drive, and 33's . 55 mph was @1300, no power to pass, accelerate. My power band begins @2500. running 75 80 was great.
I switched to 4.88 3.41 in over drive. 55 is 2k and 65 is @2400ish.
Move engine forward and re-drill cross-member holes.
Driveline stays the same.
I did this in 2000 and still going strong.
I have 3:73 gears and 33" tires, cruises about 2100-2300rpm at about 65-70mph
Driveline stays the same.
I did this in 2000 and still going strong.
I have 3:73 gears and 33" tires, cruises about 2100-2300rpm at about 65-70mph
I would love to do this but I can't as the frame rail bends up and the cross member won't go
I'm not sure where exactly you're having issues, but I've done this on my '72. The frame where the transmission crossmember goes is flat for a good long way. As far as the engine crossmember goes, The big block crossmembers were further forward than the small block ones already, so I don't see that being an issue either. Maybe post some pics of the problem areas?
Oops, brain fart...72 didn't have 700r4s...
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This is the cross member I ordered that will be here in a week
I forget exactly how much longer a 700r4 is but is less than 2".
Between moving the the cross member forward and maybe the engine side of mount backwards, I would think is do able.
Between moving the the cross member forward and maybe the engine side of mount backwards, I would think is do able.
4x4 never had big block, but I don't think that the engine mount location moved for small or big block, just inline 6, in the 2wd. I have never seen a 4x4 with 6 cylinder when I paid attention to crossmember location.
I know that my '70 K10 sucks to get the engine crossmember out because the ends are so tight to the frame.
Things to consider about moving the engine forward are the clearance between the front differential and crossmember if it isn't lifted, the fan shroud length, throttle cable would need changed for a 2wd one, and transmission shifter linkage bracket would need to move.
I think you are right on the crossmember placement. I couldn't remember for sure which engine had the difference. That said, @Montanachris You can see from the images you posted that there is room to move the crossmember forward 1.5" if needed. Just need to drill some holes.
That said, I believe you are getting new driveshafts eventually anyway, so if it was me, I'd leave the engine where it is, and just move the transmission crossmember back however far it needs to go and just get the driveshafts to match the new position.
As I recall, you aren't going with much of a lift and don't plan on extreme wheeling, so your front driveshaft may even be fine as is.
