can someone help me? I have a 1972 442, the block casting numbers is 395558-2 and the head number is 3A. the motor is said to have been redone when I got it. it has a four speed manual in it, and ***** in gets but when I get it up to about 70mph it seems to redline but I have so much pedal left what can I do to fix this

 

It's redlining in 4th gear at 70? And what do you mean by 'seems to redline'.

 

yes, in 4th gear. the rpm is way to high. seems like if I stay in it something will give way. motor has been mod but don't know if the rear end has been done or not

 

it has a 350 motor in it with 455 vale heads, at least that's what I was told

 

The block is a 350 from earlier than '77, and the heads are '77-'80 350.


Seems to? What exactly does that mean.
Either it redlines or it doesn't redline.
And where exactly is your redline?



What does this mean? Are you expecting that if the pedal goes down farther, the car should go faster?



Well, the heads are from a 350, so they're not 455.
If you mean that someone installed larger valves in the heads, the 455 came with a variety of them over the years, so it might be helpful to know which ones were installed.

You may need to take some things apart, so you can figure out what you have, so you can get it tuned and set up properly.

- Eric

 

yes it has bigger valves. also the car will go faster but starts to heat up. temp sits at 190 at 70mph with rpm at about 6rpm but when I start going faster temp starts to rise to about 200 degrees and motor sounds like its redlining. also the gears seem real short.

 

what rear end is in it

 

not sure, but maybe I should start there with the rear end. I do know its not a posi

 

So you're saying that some part of the current cooling system is inadequate.

Time to go through and check the radiator and water pump, make sure the lower hose doesn't collapse at high RPMs, and make sure the inside of the motor isn't scaled up.
A high-flow thermostat probably wouldn't hurt either.


Now back to the previous question:

What the heck do you mean, "motor sounds like it's redlining"?
What does a motor sound like when it's "redlining"?
Never mind the sound, Is the motor actually redlining?

How fast is the motor revving when this sound occurs?
What is this motor's redline?

- Eric

 

sorry Eric, but I don't know the motor redline. I just think by the gears being so short that the rear end may be geared wrong making it red line and the rev real high at 70 mph. I may just take it to the speed shop and have a bigger gear put in it. thanks guys for your help I will let you know how it turns out

 

For the love of all that is holy and burns oil,

HOW FAST IS THE ENGINE TURNING AT 70 MPH ?

What does a guy have to do to get an answer to a simple question around here, especially one that is directly related to the poster's query?

- Eric

 

Eric calm down deep breaths lol

 

Heh

Lack of Communication, lack of.

nice call mr merbach

simma donna

 

Do you have a tachometer? if so you can read the RPM'S from that to know if its redlining or not. You said at 70 mph its running about 190 degrees and the motor is turning 6 rpm. That 6 rpm is times 1000 so your turning 6000 rpms, IF your reading this off of a tachometer. If this is so then you dont want to go any faster as your motor has reached its peak RPM. Any faster for a prolonged period of time could destroy the motor. Most Olds motors dont wind up like Chevys do. And i would say 190 degrees at 70mph and 6000 rpms is not bad. It sounds like you have a LOW geared rearend. The bigger number like 3.90 or 4.11 the lower the gear. A low number like 2.73 would be a higher geared rear which will let you go 70 mph and keep the RPMS down lower, thus much farther from REDLINING. Now im no pro and theres plenty of guys here that know more than me, im just trying to explain some things to you. There are several ways to determine your rear gear ratio, one is to get the numbers off of the ring gear in the rearend, the other im not familiar with, turning the rear wheels and counting driveshaft revolutions. Maybe someone will explain that to you.

 

My 85 442 with OD trans and 3.73:1 gears goes about 2700 RPM at ~70 mph.

If you cannot go faster than 70 because your engine is maxed out at RPM at 6000, your must have hella gears like 4.33... or try shifting out of 2nd!

 

I think is the answer you're looking for MD.

JJ it sounds like your gearing is off then. I have no idea who teamed that transmission with that rear-end ratio, but 70 at 6krpm in 4th gear is nuts.

I'd start by seeing what your rear end is first and go from there.

Also, don't stay up in that RPM range for long in an Olds engine. Unless you like to grenade your block

 

OMG, I completely missed that.

Wow, it's like telling time: "The little hand is on the one, and the big hand is on the five." --
The red needle is pointing to the six, so he must be turning 6 RPM.

How cute.



Okay, let's just calculate this out.
The OP has not told us his tire size, but standard tires on a '72 A-body were about 225/70x14, which have a circumference of 83" and turn 764 times per mile.
764 revs per mile times 70 miles = 53,480 revolutions in 70 miles.
This means that if he drove 70 miles in one hour, the rear tires would go around 53,480 times, so if we divide by 60 minutes in an hour, we get 891 revolutions per minute at 70mph.
If he tells us that he is turning 6,000 RPM at 70mph in top gear (1:1 ratio, unless he has an overdrive top gear ), then 6,000 ÷ 891 = a 6.73:1 rear end.

Methinks something here is not quite right.

- Eric

 

Check the vacuum line on the tranny. I had mine pop off and I was turning about 6k rpm at 70 because the tranny wasn't shifting.

Never mine just re-read the op has. A 4 speed.

 

Yeah, something is way off

 

It sure is. His clutch is gone.

 

Could be. You'd think he'd smell it, though... Or were you speaking figuratively?

- Eric

 

No, Eric, quite literally. What other explanation for his symptoms?

I've driven plenty of cars with bad clutches that didn't smell unless they were severely over heated. I don't know anything about the OP's experience with sticks or his mechanical knowledge to make a decision about him.

Paul

 

Hey, could be, but in my own experience, any time i had a slipping clutch, it was obvious, and I definitely smelled it whenever I got on it.

That and the tachometer that tended to wander upward were quick giveaways.

But okay, it's possible.

'Course, I'm going with the figurative meaning...

- Eric

 

The OP states the tach is way too high. I stand by my statement.

Paul