Just got the olds 350 swap done.. and a couple rear end ???s

[87MonteSS]

Re: kk

I have stock gearing for now and the 200-4r transmission.. we put it up on a hoist and found out the shift linkage was gettin caught by the exhaust..

but onto further things.. it flies now but is super super slow off the line!!

like i hold the brake and the gas and it sits around 2500 when the tires dont break and i let go of the break and it just slowly accelerates like literally lags for a second or two until it hits around 28-3000 rpms then it flies.. oh can i get it to sit at around 2800 rpms or get it so it doesnt lag so bad.. will gearing effect this.. because i plan on upgrading to 3.73s or 4.10s in the near future..

and ona side note.. any tips on installing a floor shifter??

You need to take a step back and a deep breath before you go any further.

You bought a 2800RPM stall converter and it sounds like you don't know why you did that. There are a number of things that affect performance and how fast a car is or how quick it is. There's a difference between fast and quick and it sounds like you want your car to be quick.

Taking that into account you need to consider the following:

What is the power band range for your cam? This will determine the proper stall speed for the torque converter and this is where the 2500 RPM with the wheels locked up comes in. A 2800 RPM stall converter is a baseline number, in other words the 2500RPM you're seeing is the converter stall speed based on your tach, which may or may not be accurate. The only way to get that RPM higher is with a higher stall converter.

How much power and torque is the engine making? If there's a sharp power curve or the torque is all at the bottom end you may have gone over the torque curve with the converter you chose. By your description of the symptoms you're having this is likely part of the problem you're having. You didn't mention if the trans shifts to second gear at the 2800-3000 RPM mark or if the acceleration you feel is still in first gear. If it's after the 1-2 shift that tells me that the torque/power band on your engine is below 2500 RPM, OR your rear gear/tire combination is too much (see below), if it's still in first gear then there may be other problems such as fuel delivery or ignition timing. It could also be because of the rear gearing, which you still haven't told us. To say it's "stock" could be a number of different ratios.

3.73 is the stock gearing for the Monte Carlo SS with a 200-4R trans. It's driveable and still good on the highway. 4.10 gears will tear the tires off in no time and will affect highway RPM by just over 9%. Depending on the tire size in the rear and how often you'll be on the highway this may or may not be a factor for you.

Keep in mind that rear tire size affects the performance as well. Effective rear gear ratio is changed by the size of the tires as well. If your stock gears are in the 2.xx range and you're running tall tires it would explain why you're seeing what you are. Shorter tires will get the performance back on numerically low ratios.

Things to check first:

Base and total ignition timing
Rear axle ratio
Rear tire size
TV cable adjustment

By the way, is your new converter a lockup converter?

 

[82355supreme]

Two things here. 1st, it sounds like when you say radical cam it's VERY radical, over 250* @.050 which tells me that even with a 2500-2800 stall it's not enough, especially with the stock rear gears, which are probably 2.78 or 3.08 Yes, 3.73 or 4.10's will help.

2nd is if the trans is shifting too early the Kick-down cable, T.V. cable, whichever you want to call it, is out of adjustment. On my TH350 I don't have the kick-down cable hooked up & unless I manually shift the trans, it will shift at 3-3500 rpm even if my foot is planted to the floor. Under light throttle it shift by 2000 rpm. This of course is my choice not to have the cable hooked up.

Hope this helps.

 

[joe_padavano]

2nd is if the trans is shifting too early the Kick-down cable, T.V. cable, whichever you want to call it, is out of adjustment.

Unlike the TH350, the cable on the 200-4R also controls the upshifts. The TV cable actually acts like a mechanical throttle position sensor and replaces both the kickdown function and the vacuum modulator used on the earlier transmissions.

 

[82355supreme]

Yes, correct, that's what I said. That's why the trans is up-shifting too soon. 🙂

 

[t_visker]

ok

ok, first i would like to say thank you guys so much for the help..

i am running idk for gearing.. im guessing 2.xx something.. and i have stock stire size on 14x6 rims.. not sure wat that would be.. i am puttin in a posi locker and 4.10 gearing once the money comes in.. i already have the locker.. just need the ring and pinion..

im not sure how to mess with ignition timing...

but when im power braking.. i keep traction most of the time.. and it sits at 2500 rpms.. then i let go of the brake and it goes slow.. but once it hits around 3000 it hauls major *ss.. and some times burns out their.. then it goes to around 5 grand before i shift it into 2nd.. and its still flying..

idk if im not explaining good enough please let me know.. and if any of you have msn and would like to try and talk to me about this add me.. [email protected] is my addy..

btw this is a big help!

 

[82355supreme]

Once again, what's your cam specs. IE lift,duration,lobe seperation angle.

The lousy stock gears will wreak havoc on low-end accel.

I don't think timing has much to do with it, but to get it dialed in you'll need to get or borrow a good dial-back timing light.

 

[skife]

definatally your kickdown cable, also, play with the governer on the transmission, try some heavier weights in it.