Hi guys, I just got a 1985 chevy camaro with a 305 tpi 5.0L. But the problem is it has a broken transmission, from what i read on wikipedia the transmission they come with from factory is a 700r A friend of my said to me he has a th350 and know someone that can overhaul it and make it better for dragracing purpose. (the mods I will do later on the engine is to put down ET's between 13.5 -12.5(NOS)) The engine is stock but I'm planning to add more power to it and maybe use drag radials. I would like to use the car on the street normaly and as a weekendracer at the local dragstrip. So here is the question: 1.)What do u recommend me repair the 700r or install the th350 (overhauled to be better)? 2.) Would the th350 fits directly because in the info page on tci.com website I saw that the diameter of the th350 is 19 1/8'' and the 700r is 20''? 3.) Would the th350 hinder my daily driving? Would I lose topspeed because there is no overdrive? 4.)Do I need a oilcooler with the th350? Thanks in advance Chris from curacao www.curacaodrag.com

With the 700R4 you'll get better mileage, and it just bolts into the car.

A TH350 doesn't have a torque arm mounting provision, so you'd need to deal with that.

The engine will limit top speed more than the transmission.

All automatics need a cooler.

Oooh Ok, so I have to find aditional parts in order to install the th350.(sounds like headache) And I would gas higher fuel consumption( live on a small island with no highways but there is alot of traffic), I will ask how much it is to repair and rebuild my 700r and make it bullet prove like the th350. Better?

I doubt you would see any benefit from an OD transmission then. The occasional highway use won't be a big deal. Gear ratios will make a big difference in mileage and performance. Something in the mid 3.xx range will probably work well for your car and still keep the rpms low enough on the highway. If you build a high rpm engine for HP then try driving down the highway at low rpms, you'll do more harm than good. TH350 were around for many years in millions of cars going down the highways long before OD were standard. It never hurt those engines. Everyone now seems to be afraid of a transmission if it doesn't have an OD.

It's not that hard to swap over to a TH350. The easiest way is with a long tailshaft TH350 (9"). That way you can still use the 700R4's driveshaft. If you have a short 6" tailshaft TH350, you need a driveshaft out of a 82-83 third gen that came with the 200c 3 speed.

The easiest way to do the swap is with a conversion kit. It provides a way to attach the torque arm to the TH350 and it supplies an adapter to move the tranny mount 2" forward. You'll need to provide a manifold vacuum source for the modulator valve.

OK OK, thanks!! tomorrow I will know for sure the lenght of the 350 I will get.

I went to b&m and tci but did not find the conversion kit. Do you know anyone who did it so get a document from him or a forum where its writen about the vacuum scource?Or do I just have to choose one and just put a 'T' to get a hose from it?

BTW the tranny mount you talking about is the one from my camaro itself?and by what you say it means that the th350 and 1985 700r4 has the same amount of splines?

Chris

http://www.jegs.com/p/Hurst/746223/10002/-1

I have had both transmissions in my z28,first i put in
a th350 from an '80 z28-used the aftermarket B&M
torque arm kit,original driveshaft,original th 200 x-
member,cooler and modulator lines from the '80 z
liked this tranny and it worked great.
Later i decided to get the A/C working again and didn't
want the A/C compressor running at 4000 rpm when
cruising down the highway so i got a 700r4,put a shift
kit in it and installed using '83 camaro driveshaft and
X-member.
th 350 is better for drag racing-better gear ratios
(700r4 has big gap from 1st to 2nd)
did not notice any major difference in fuel econ.
between the two trannys. (did notice the 700 r4 ran
cooler oil temps on the highway-probably because the
700r4 uses a varible displacement oil pump and lock
up converter)

Ok thanks, and last question can I use my original starter?

BTW the th350 comes from a malibu

Starter is the same,flywheel/flexplate cover is different
-get one for th 350,if the malibu is a 1978 up it might
have a "multicase"bellhousing(both chevy andB.O.P.
bellhousing)-don't know if one of those would cause
any clearance problems.I can't remember if the earlier
th 350's speedo gear fitting is different or not-the '80
th 350 i used was the same as original cable in my car
1978 up th350s have a few minor improvements over
earlier,most '81-86 th 350 have a lock up converter.

Ok I decided to go with the th350 because I rememberd that my original 700r4 is pre-87 and those one are pretty weak from I read from this website.
So I paid the guy yesterday to get the th350 and also to get a guy to do the overhauling and make it bulletproof so it can hold the abbuse I'm going to put it thru. hope everything goes well I will get the transmission on friday.
He has done the same swap on a 82 camaro(came factory with 305) with a 350 carburator in it. He showed it to me and he had used his factory transmission mount.
But anyway I will let u know how it went.
thanks once again.

The TH350 is hardly bullet-proof. I've seen at least 20 of them scatter parts all over my local track behind pretty low HP engines. Their ONLY advantage is the better first-second ratio spread.

You can easily build a TH700-R4 to stand 400+ ft/lb all day long with the right cooler. You'll burn up your 10-bolt axle at that rate long before a good TH700-R4.

I use a TH350 with approx. 530 horse with a pro charged small block pushin 12p.s.I. for over 9 years. 3500 stall. street car but not daily driver. drive approx 50 miles round trip during heat of summer with intercooler in the way of the radiator to my cruise night. Race it almost every week in the summer.
The key is to get a v8 core th350. they have 3 v.s. 2 intermediate clutches, five v.s. four direct and forward clutches, 5 v.s. 4 low/reverse clutches. I use the more expensive B&M shift kit because it uses the transfer plate to triple the third gear holding power. I also use a heavy duty bolt in center support as that is a weak link-stock only grabs one set of lugs in the case and this one uses two and also uses a wide 700r4 sprag!. I'm using stock clutches. Make sure to replace all the rubber that applies the pistons including the ones in the low reverse in the back of the case as a lot of builders don't take the time to do that set of rubber. Using a TCI converter 3500 stall the whole time. goes 11's all day long 116mph. hope that inspires you to do it right-you'll be glad you did.

I dont know nothing about the internals of any transmission (didnt reach that level of skill yet). The friend of my who told me of the builder said he does it very good and said to me he will make the transmission race ready and that it can withstand any abbuse I will give it. He said I can use the stock converter the transmission has because is was in a car that was being driven so it allright he will clean it up and fill it with fresh oil. (He known more about those thing that I do).
BTW I asked him about a cooler and he said I can use the factory in the radiator.

One question what is that ''Torque converter lockup switch do''? Is that kinda 2-step or stall, do u recommend my to do it?

On 28 feb I will go to the track to test it with the engine stock as it is but with the th350 I'll hope to get some mid-15 with it.

You won't be able to use the 700r4 converter with the
350 because they are different. I like to use converters
that have been rebuilt by TCI,B&M or other companies
because those have"brazed"fins for greater durability.
Depending on how you use the transmission,the
cooler in the radiator may or may not be enough to
keep the fluid cool(most of the heat is generated by the
fluid being thrashed in the torque converter when the
converter is turning faster than the tranny input shaft)
A transmission temperature gauge is recommended
to monitor trans oil temp during heavy duty use
for my trans cooler i took an oil radiator from a junk
cop car and mounted it in the area underneath the
battery with an 8"electric fan(i used a cut down and
modified chevy citation fan,a fan salvaged from an
ATV or motorcycle would be good too) a thermostat
in the transmission pan turns the fan on at 200f.
With a lock up converter,there is a clutch plate
that "locks up"the converter to increase highway
economy during cruise conditions-converter "unlocks"
when under throttle so torque multiplication can
occur -if coverter stays locked low-speed acceleration
will be sluggish.

Ok, but I was talking about the converter from the th350, I was allready told that the 700r4 converter wount fit.
I will start ott with the original cooler and watch how its going, till the end of the month, but I will install an oilcooler later.

For drag racing i would be tempted to get a converter
with a higher than stock stall speed,around 2400 rpm
(stock are around 1600-1800 rpm)-"stall"speed is the
theretical speed that the engine can rev up to with the
tranny input shaft locked,actuall stall speed depends
on the converter size and design and engine torque.
If stall speed is too low for the engine it will bog off
the line,if stall speed is too high for a given engine
it will just slip and waste power.

did you buy a th350c?
that one has a lockup torque converter
most people don't even hook up anything to the wiring they just drive it with a three speed with no lockup
if it is a 350c it takes a different shift kit/the builder will probably short you there because he is probably only used to working on regular th350's so be on top of that.
th350c's aren't so bad in fact they seem to last about the same.

Does this mean that with my stock converter I can launch @ max. 1800 rpm?Is this enough for my engine or will it bog, btw how do u launch with the e-brake or do u have msd?(2step)

To ed o:I read about the 350c but I think mine is just 350. And if the builder has a good knownledge he must know about the difference.

if it is a th350 and not the 350c it takes a non lockup converter.
park brake won't help you stall it up for a better launch.
stock converter would be lucky to stall that high/not really a performance enhancer
as a side note the stock converter will provide more positive shifts than a higher stall one
does this "builder" give a warranty if the trans doesn't work? should know that.
I like the more expensive B&M shift kit for the TH350/it seems to work great every time

Sup, talked to me fiend today he said to me that the overhaul kit is a B&M kit item number 30299 something like that.I hope i can get my transmission back on saturday so I can install it emmediately.

The other camaro the guy was talking about is probably mine. carbed 355 but it had a th200 in it and not a 700r4. The th200 crossmember wil work fine for a th350. The 700r4 crossmember won't. Unless you use the conversion kit from b&m or hurst.