Engine/Trans help

[Tio Pancho]

Rebuilding a 77 Cherokee Chief for my daughter. Stock AMC 360 w/ small cam. TH400 transmission. Rotating assembly is out for balancing and realized I need to match my flexplate to the torque converter. New flexplate doesn't match existing converters bolt pattern.

Plan on running 33 x 12.50 tires with a small lift. Front and rear are Dana 44 w/ 3.73 gears.
This will be my 16 year old daughters daily driver. Will also see some light wheeling and camping. Will probably tow an 18' jet boat.

Looking for input from the pros for torque converter choice. Will match flexplate to that.

Thanks in advance.

BTW - machine work is being done by Jody at Carquest in Upland. They have been great to deal with so far.

 

[monkeyswrench]

With it being a daily, I personally would go with about a 2000 stall, and no more. With the tire size and gearing, much more than that may want to feel "sluggish", not wanting to flash the stall until highway speeds. The more the converter slips, the more fluid shear you have, and that just means more heat. Never a good thing.

That said, I've broken more transmissions than I've built. Hopefully a transmission guy will chime in.

 

[Tio Pancho]

Thanks. That’s what I was leaning towards.
I am sure others will chime in.

 

[rivermobster]

77 has to pass a smog test...

Keep it bone stock.

Tavo-Matic in El Monte for the parts.

 

[rush1]

Yep the smog deal in California will kill you not only that the state lowers the acceptable levels every couple of years so you may pass now but might not in 2 years. California wants all of the old cars off of the highway. But if I put a converter in that a mild 2000 to 2400 stall no more than that.

 

[Tio Pancho]

I am aware of the smog issues. It will have all the smog equipment etc. Other than the very mild cam there are no changes.
Just need the info for the torque converter to ensure a correct choice

 

[monkeyswrench]

Oops, sorry! I forgot about the smog stuff. I haven't really had to deal with that much the past few years.

 

[Tio Pancho]

Bump.

 

[4Waters]

A quick search turned up this, hope it helps

Flexplate 1974-1979 360 V8

Flexplate 1974-1979 360 V8

www.bjsoffroad.com

 

[Tio Pancho]

Funny thing is that’s the flex plate I bought. After more research I have reached out to Transtar for toque converter advice. If I need to change foexplate they are cheap. Need to ensure converter is right.

 

[Moneypit]

Stock stock stock.... No need for a "stall" in a stocker. (IMO)....Any built in "slip" will hurt economy, especially towing...You, or her,aren't trying to set the world on fire with power launches. All the "stall" will do is allow the engine to get Rs on it's way to a "happy spot", a spot you may never find with that AMC 360...Leave it stock and enjoy it as it was intended from the factory. (Those factory guys are pretty good at getting things right)
Just my .02 worth,
Ray

 

[Carlson-jet]

Stock converter is fine.
While it is apart, be sure to check the block is clear of the casting sand. They had issues 77-78 with not getting all the sand out of the cooling passages.
Replaced a few back in the day due to over heating issues.

 

[lbhsbz]

Stock Stock Stock.

I would go so far as to NOT replace anything that's original and still functions halfway properly, because the aftermarket replacement garbage will perform worse (EGR/AIR/distributor...etc)...and likely cause an emissions failure.

Is the same Tio Pancho who's jet boat motor I fixed after that dumbass with a bridgeport mill who called himself an engine machine shop fucked it all up?

 

[Tio Pancho]

Yes it is. How you doing Pat?

 

[Gelcoater]

Stock stock stock.... No need for a "stall" in a stocker. (IMO)....Any built in "slip" will hurt economy, especially towing...You, or her,aren't trying to set the world on fire with power launches. All the "stall" will do is allow the engine to get Rs on it's way to a "happy spot", a spot you may never find with that AMC 360...Leave it stock and enjoy it as it was intended from the factory. (Those factory guys are pretty good at getting things right)
Just my .02 worth,
Ray

This was my thoughts too.
The 360 isn’t a rev machine, wouldn’t want a converter to flash half way to redline, which a 2000 or 2400 would absolutely do.

A “mild cam” like he has may up the number slightly. Maybe, lol.

Stock numbers
175hp @4,000
285 lb/ft @2400

The 401 was rated at 215hp 320tq

An LS swap would be fun

 

[johnnyC]

unless its exempt from smog tests don't change it from stock, you will fail your smog test, have a 91 jeep ...stock. last go around with registration ca wanted it tested at a star inspection station it failed, couldn't meet the emission # the state wanted , was told the standards were lowered had to change the cat in order to pass first time in 19 yrs...... bs

 

[rivermobster]

unless its exempt from smog tests don't change it from stock, you will fail your smog test, have a 91 jeep ...stock. last go around with registration ca wanted it tested at a star inspection station it failed, couldn't meet the emission # the state wanted , was told the standards were lowered had to change the cat in order to pass first time in 19 yrs...... bs

And how much did That cost you??

Cats are not cheap anymore. Those days are gone. It sucks.

@Tio Pancho

Any cam that has Any kind of longer duration or overlap will NOT pass smog at idle. You can go with an RV cam, that has maybe a bit more lift Maybe, but that's it. And I'm not even sure I would try that idea these days.

If someone makes a cam marked as CARB legal, then you are golden. They will supply a sticker for your engine compartment with it.

Again, Tavo-Matic in El Monte for the converter and flex plate. They will have everything you need in stock.

 

[johnnyC]

if i remember correctly abs. 600.00

 

[LargeOrangeFont]

And how much did That cost you??

Cats are not cheap anymore. Those days are gone. It sucks.

@Tio Pancho

Any cam that has Any kind of longer duration or overlap will NOT pass smog at idle. You can go with an RV cam, that has maybe a bit more lift Maybe, but that's it. And I'm not even sure I would try that idea these days.

If someone makes a cam marked as CARB legal, then you are golden. They will supply a sticker for your engine compartment with it.

Again, Tavo-Matic in El Monte for the converter and flex plate. They will have everything you need in stock.

CARB legal cams don’t exist for a 360 that I am aware. but a higher lift grind with a wide LSA and minimal overlap and duration would work.

COMP actually makes a couple CARB legal cams for LS engines however. Those are the only ones I’ve ever heard of.

I’d call the COMP Cams helpline and tell them what you are trying to do and see if they have some options. They can easily do a custom grind for you.

You could try a new 49 state cat first. They are pretty cheap.

 

[rivermobster]

CARB legal cams don’t exist for a 360 that I am aware. but a higher lift grind with a wide LSA and minimal overlap and duration would work.

COMP actually makes a couple CARB legal cams for LS engines however. Those are the only ones I’ve ever heard of.

I’d call the COMP Cams helpline and tell them what you are trying to do and see if they have some options. They can easily do a custom grind for you.

You could try a new 49 state cat first. They are pretty cheap.

Corrected your post eh?

LoL!

 

[LargeOrangeFont]

Corrected your post eh?

LoL!

Someone would have if I didn’t clarify lol.

The CARB legal cams are only legal in a specific make and model the CARB cert is good for anyway.. the exception there may be if you have a BAR certified engine swap.

But as you know, any CARB cert is for a make a model, not blanketed across a engine family.

 

[Carlson-jet]

With these old school engines, retarding the timing just a touch and leaning out the idle mixture screws and opening up the butterfly to get a good idle number will help pass smog. Don't go to far or it flips and I think the NOX #goes up. The PCV system is critical to keep any oil from entering the combustion cycle. It also helps to run the lowest octane fuel during the test.
Once a certificate is issued readjust to best performance. With todays fuel blends it should be fairly easy to make these old engines pass.
I learned all this through a Voc-tech Tuneup and emissions control at Santana High in Santee when I first moved to CA. in the 85'.

PCV not PVC. edit LOL .

 

[Tio Pancho]

Thank you all for the help. Joe I will reach out for the flexplate/TC help.

 

[LargeOrangeFont]

A bottle of rubbing alcohol with less than a 1/4 of gas will clean up the emissions for the smog test too..

 

[Gelcoater]

Someone would have if I didn’t clarify lol.

The CARB legal cams are only legal in a specific make and model the CARB cert is good for anyway.. the exception there may be if you have a BAR certified engine swap.

But as you know, any CARB cert is for a make a model, not blanketed across a engine family.

I’d be looking at Edlebrock.
If anyone has a carb compliant cam and/or intake for the Jeep 360, they probably will.

Not sure how well it would work without headers, but?