Camshaft instal inquiry

[Phreakish]

Wasnt the stock on a 68 340 gts a 22-2400 stall? The Tc is filled right now with a bunch of bright red fluid lol. 3k rpm stall? That's high no? Or will it help with low end power?

Stall is a complicated topic. 3k is not high if done right.
There's high, low, loose, tight.. it's hard to describe.

The same TC behind two motors will drive VERY different. They're torque drives. You put in a certain amount of torque, a certain amount comes out. Stall speed is also determined by how much torque your engine can make, higher torque production actually results in a lower stall RPM (to a point). As the rpm increases, the ratio of 'slip' or in versus out changes. The more 'slip' there is also results in 'torque multiplication'. Basically, a TC is a fluid driven gearbox that's full of magic. Good, bad, happy or sad magic all depends on what you put in front of it and how the TC is setup. If your converter begins to stall at 2200 rpm, but your torque peak is 3500 - it's going to feel like you took off in second instead of first. If it wants more torque than your engine can supply, it's never going to smoke them tires or feel very motivated. Will generate lots of noise though! The challenge is to get the converter to 'slip' where you're under operating torque and to stall at or under your peak torque (how far under is a matter of consideration, typical is 500-700 rpm under).

All this to say: what is labelled a '3k stall' converter behind a 750hp big block 440 is NOT a 3k stall behind a 150hp 318. How it drives will also be significantly impacted by your gearing and weight. The stockers were good 'for their day' but are not good by modern standards. Lots of compromise back then in order to hit the production volume. Modern ones take far better advantage of modern manufacturing an also modern knowledge and application.

 

[Phreakish]

Lol 800 is more than all my installed parts combined I definitely understand what everyone is saying though on the cam and TC and I'm see more now how every piece of the build intertwines to make the final product perfect.

I also just read a huge Aj posted in a different TC thread. I definitely need to read into them more before trying to see if I can sneak one into the garage without the wife noticing. 1 step at a time and my car will one day be without want/need more more parts.

But I'm going to order valve springs... and I think I'll need some gaskets for when doing the cam. I wonder if I should wait until MATS to start buying parts maybe there are sales there?

I hear that. But also read up on what people have had to say about off-the-shelf converters. They may be cheap, but in most cases their performance is nearly stock, if that.

It's also possible to find used converters for a good deal, just be wary of who you buy them from. Every racer is eyeing a new converter, but needs to sell their old pile of garbage to get it - so know the car and owner before hand. The good ones will even be able to put you in contact with the maker to see if it's a good fit for your combo.

Nearly $1k for a converter may seem like a lot, but you'll be amazed at the difference. It would be like a whole new engine. Just think, $1k isn't bad for a 'new engine' ;)

 

[Wyrmrider]

DD
you have a converter
just put it in and gt your car going and do some baseline tests
most likely it's a 340 converter, maybe stock
does not matter
if it works for you great
if not a converter guy can figure out what you need and how high to jump and how far
you might get lucky
do not make a buch of changes all at once
pulling the trans and changing converters is easier than new pistons for example
KISS
and keep posting and learning as you go

 

[DentalDart]

DD
you have a converter
just put it in and gt your car going and do some baseline tests
most likely it's a 340 converter, maybe stock
does not matter
if it works for you great
if not a converter guy can figure out what you need and how high to jump and how far
you might get lucky
do not make a buch of changes all at once
pulling the trans and changing converters is easier than new pistons for example
KISS
and keep posting and learning as you go

That converter is in my 727, I have a 904 in the car now lol.

Thanks a bunch for the help!

 

[69_340_GTS]

I'm no torque converter expert. But I do think you can go "off the shelf". You don't have some unusual exotic combination. 727, 3.23 gears, hot rod 340, light A-body... someone has a converter that they mass produce that will be "close enough".

Gaskets for cam change? You can buy a set just for that that. I know Fel-Pro has one.

 

[DentalDart]

I'm no torque converter expert. But I do think you can go "off the shelf". You don't have some unusual exotic combination. 727, 3.23 gears, hot rod 340, light A-body... someone has a converter that they mass produce that will be "close enough".

Gaskets for cam change? You can buy a set just for that that. I know Fel-Pro has one.

Yea gaskets- water pump, valve cover gaskets, and I think that may be it.

I like off the shelf tc idea too so will my pocket book.

 

[fishmens67]

Turbo Action 3500 is what you want. The best shelf convertor hands down

 

[DentalDart]

Heres that cam card of the 1789. I'm going to do some reading on it to try and make more sense of it.

 

[sireland67]

Is that cam card wrong?
I bet the cam that is the engine now is bigger.

 

[DentalDart]

Is that cam card wrong?
I bet the cam that is the engine now is bigger.

It's the cam card for the 1789 cam, first time ever taking it out of the box. Why do you think my current cam is bigger? Heres my idle and my car driving.

 

[RustyRatRod]

Heres that cam card of the 1789. I'm going to do some reading on it to try and make more sense of it.

View attachment 1715480491

That's a really nice cam. It's the Crane 272h10. Same exact cam. Crane has always ground the Summit line. That's why they're good cams. Here's the Crane. Same exact specs.

https://www.summitracing.com/parts/crn-15005

 

[RustyRatRod]

It's the cam card for the 1789 cam, first time ever taking it out of the box. Why do you think my current cam is bigger? Heres my idle and my car driving.

The 1789 is at least one step up from that. Maybe more. It will have a noticeable idle. Here is the same cam in a Chevy 350.

 

[DentalDart]

The 1789 is at least one step up from that. Maybe more. It will have a noticeable idle. Here is the same cam in a Chevy 350.

You're the man! I just watched like 10 videos of the cam and it sounds pretty nice.

Thanks so much, really I know you and others may be tired of my questions and responses, but really I'm learning so much as we go! One day I'll be the old grumpy guy maybe, but right now I'm stuck on learning and trying to get everything out of everyone.

I wish I had a limitless budget, I feel like there is so much to do!

 

[RustyRatRod]

You're the man! I just watched like 10 videos of the cam and it sounds pretty nice.

Thanks so much, really I know you and others may be tired of my questions and responses, but really I'm learning so much as we go! One day I'll be the old grumpy guy maybe, but right now I'm stuck on learning and trying to get everything out of everyone.

I wish I had a limitless budget, I feel like there is so much to do!

No sir, not tired at all. You're at least listening and that's what counts. Nine times out of ten, the old "use what you have" adage works pretty well. Well, you're like most of us and have to do it a little at a time. I gave up a long time ago wanting to really build a barn burner. It's simply not in the budget.

 

[crackedback]

Just a guess... that cam you bought won't run significantly different than the one in the engine now.

The other thing... why are you taking a 904 out to put a 727 in? JMO, that will SLOW the car down a BUNCH. You know you need a different driveshaft and yoke for the 727 too. I would NOT make that swap. I dislike 727's behind any SB to start with. Unless you are pushing 600hp... then maybe the 727 is a good choice.

 

[DentalDart]

No sir, not tired at all. You're at least listening and that's what counts. Nine times out of ten, the old "use what you have" adage works pretty well. Well, you're like most of us and have to do it a little at a time. I gave up a long time ago wanting to really build a barn burner. It's simply not in the budget.

Definitely little at a time. It's hard to limit myself when I just have new parts lying in the garage. I also always fear that I'm putting the wrong thing in my car, like with the cam. Take my rear end for example I went from open 7.25 to bigger tires with more grip and sure grip and now I dont spin like I used to but feel like the car could use more low end power.

A cam and tc like everyone has mentioned probably wake me right back up. That and a good carb tune. I also want to be able to hit the skinny pedal while going 30-40 and feel it go!

 

[Wyrmrider]

Looking at the cam card you can see it has the same patter for intake and exhaust and is most likely symetrical
you know the duration at .004 is 272 because that's what Cam Dynamics- who was bought by Crane used and what Crane uses
given the lobe centers you have you can figure the .004 timing and overlap
Agree with RRR- You are listening or we would not be trying to give you our opinions- you still have some sorting out to do because opinions vary
and don't buy a cam for the sound
now on the converter
put a known one in and do a stall test and see how it drives
if you then still need a different converter you at least can give the builder a clue
remember the amount of torque you generate will change your stall speed and you need a converter for YOUR build

 

[DentalDart]

Just a guess... that cam you bought won't run significantly different than the one in the engine now.

The other thing... why are you taking a 904 out to put a 727 in? JMO, that will SLOW the car down a BUNCH. You know you need a different driveshaft and yoke for the 727 too. I would NOT make that swap. I dislike 727's behind any SB to start with. Unless you are pushing 600hp... then maybe the 727 is a good choice.

Because I want to install my floor shifter.
Yea the DS part sucks since mine is brand new but I'll cross that bridge when I get there, I'm thinking it would be a next year project. I just got the last piece to be able to install my floor shifter which is exciting.

 

[crackedback]

Before I dug into ripping the engine down... If you don't have one, grab a dial indicator and magnetic base. I'd remove one of the rocker shafts, use dial indicator to see what the lift is at the top of the pushrod. That will give you an idea regarding lobe lift what is installed currently.

You can get parts to use a floor shifter with a 904.

 

[DentalDart]

Before I dug into ripping the engine down... If you don't have one, grab a dial indicator and magnetic base. I'd remove one of the rocker shafts, use dial indicator to see what the lift is at the top of the pushrod. That will give you an idea regarding lobe lift what is installed currently.

You can get parts to use a floor shifter with a 904.

I'd have to open the valve covers to do that,do I need any special tools to remove the stuff and put it back together?

Well I got the 727 and all the parts except 1 with my car. The 904 works, and I've messed with my shift cables but it's still not the best. One of the transmissions I want to rebuild and the 727 is already out of the car, so the 727 gets the nod... plus I can say I have a 340 w/ a 727 like all the cool guys!

 

[crackedback]

It will be slower/heavier with the 727. And the inherent issue that 727's have that 904's don't. No thanks. I'd run a 904 behind a street SB.

Cool guys???


Your car, your deal.

 

[yellow rose]

It will be slower/heavier with the 727. And the inherent issue that 727's have that 904's don't. No thanks. I'd run a 904 behind a street SB.

Cool guys???


Your car, your deal.

I agree 100%. The 904 is the ticket for the OP.

 

[pt70]

727's had a 10 3/4'' and an 11 3/4'' converter and likely others. You would want the smaller diameter one [if you're going original equipment].

 

[furrystump]

Is the 904 slipping or tired? Have it rebuilt. It has like 15 lbs less rotating weigh. It will not exploded and come through the floor like a 727 can and and it is overall lighter. With a quality rebuild and attention to a couple of things it will live forever behind your small block. Also you need a different length driveshaft to make the swap to 727. You would need to be making SERIOUS power to NEED a 727. If the goal is a fun street car, you can buy an off the shelf converter. I wouldn’t, I personally would call PTC or Ultimate and tell them EVERYTHING about the car and what I was going to do with it. Overkill for you maybe, but you will get a converter as close to optimal for the car as you can get. I got a 410 and a 727 and wished like the Dickens I went 904, running 11.80. I don’t want to be cool, I want to be quick!

 

[DentalDart]

727's had a 10 3/4'' and an 11 3/4'' converter and likely others. You would want the smaller diameter one [if you're going original equipment].

I believe mine is the smaller one, but like gts340 said it's an unknown trans and converter.

Is the 904 slipping or tired? Have it rebuilt. It has like 15 lbs less rotating weigh. It will not exploded and come through the floor like a 727 can and and it is overall lighter. With a quality rebuild and attention to a couple of things it will live forever behind your small block. Also you need a different length driveshaft to make the swap to 727. You would need to be making SERIOUS power to NEED a 727. If the goal is a fun street car, you can buy an off the shelf converter. I wouldn’t, I personally would call PTC or Ultimate and tell them EVERYTHING about the car and what I was going to do with it. Overkill for you maybe, but you will get a converter as close to optimal for the car as you can get. I got a 410 and a 727 and wished like the Dickens I went 904, running 11.80. I don’t want to be cool, I want to be quick!

Yea didnt they save like .3 seconds between the 2? I was reading about a test they did back in the day.