What is needed to stroke a 360 LA?

[bm73charger]

Hello all,

Im new here and in need of some assistance. I have a 73 charger with a 318 and a 904 transmission. I recently bought a 360 from marketplace that the guy says was from a 1990 d150. I have taken it to the machine shop and am getting it bored .030.

I want to put a stroker kit in it (Eagle 20502 SB Chrysler 360/408 Street Strip Rotating Assembly 10.0 Mahle Dish Pistons). This will be the first engine I have ever built but I have done plenty of tinkering and am fairly knowledgeable in most aspects. My questions are about installation and function. Do I need to buy the harmonic dampener and the flex plate with a 360 torque converter to mount it to the transmission. Or will I need to have it internally balanced, with no dampener and no flex plate just the 360 converter? I have been getting a lot of different opinions on it. Some people are saying the dampener and flex plate are only for the 360 not for a stroker kit and that the stroker kit will need to be internally balance. That the harmonic dampener and flex plate are only used to put the 360 in, not the stroker (408). And others are saying that Ill need a balancer and flex plate new torque converter and all.

I just need to know what I need to make sure it goes in smoothly and docent tear itself apart hahah. To me what makes the most sense is to get the crank internally balanced, and to mate that to my 904 with a 360 converter. Is there a reason thats a no go or is that the right train of thought?

Also any other tips and tricks to make this go smoothly would be greatly appreciated, along with any concerns to look out for which may become an issue.

Thanks in advance for any help. Ill be on here pretty regularly to reply if anyone has questions or needs clarification.

 

[davek]

I would ask the place you buy the stroker kit. I would think not but not positive about it.

 

[RemCharger]

Have to decide if you really want to put a stroker in front of a 904. I wouldn't.

 

[davek]

A stock Chrysler 904 transmission can typically handle around 300-350 horsepower; however, with modifications and upgrades, it can potentially handle up to 500 horsepower, depending on the specific application and quality of the rebuild. Something I read when I thought about stroking my 318.. Wanted to keep the car numbers matching.

 

[R413]

Go to a reputable moapr trans ship like A&A and they can build you or give a parts list for a strong 904.

Skip the other mopar trans shop with 3 letters

 

[Curiousyellow71]

Typically when you buy the crank if you look in the description it will say if it is meant to be internally or externally balanced. The eagle strokers I have seen are internally balanced for a 360. Most companies that sell stroker kits charge extra to balance the rotating assembly. Don't assume the assembly your getting is balanced unless it says so.

Internally balanced you can not use the 360's original damper or torque convertor w the weight. Some of the aftermarket balancer's are internally balanced and have bolt on weights to balance a stock 360. A 318 convertor is internally balanced.

I don't really know what your performance goals are to say what would need to be done to the 904. 904s need more pressure then a 727 to get the holding capacity out of the smaller clutches. As you up the pressures...internal have to be built to suit. I would say install a shift kit minimal. A built 904 can handle a lot of horsepower though!

 

[493 Mike]

Hello all,

Im new here and in need of some assistance. I have a 73 charger with a 318 and a 904 transmission. I recently bought a 360 from marketplace that the guy says was from a 1990 d150. I have taken it to the machine shop and am getting it bored .030.

I want to put a stroker kit in it (Eagle 20502 SB Chrysler 360/408 Street Strip Rotating Assembly 10.0 Mahle Dish Pistons). This will be the first engine I have ever built but I have done plenty of tinkering and am fairly knowledgeable in most aspects. My questions are about installation and function. Do I need to buy the harmonic dampener and the flex plate with a 360 torque converter to mount it to the transmission. Or will I need to have it internally balanced, with no dampener and no flex plate just the 360 converter? I have been getting a lot of different opinions on it. Some people are saying the dampener and flex plate are only for the 360 not for a stroker kit and that the stroker kit will need to be internally balance. That the harmonic dampener and flex plate are only used to put the 360 in, not the stroker (408). And others are saying that Ill need a balancer and flex plate new torque converter and all.

I just need to know what I need to make sure it goes in smoothly and docent tear itself apart hahah. To me what makes the most sense is to get the crank internally balanced, and to mate that to my 904 with a 360 converter. Is there a reason thats a no go or is that the right train of thought?

Also any other tips and tricks to make this go smoothly would be greatly appreciated, along with any concerns to look out for which may become an issue.

Thanks in advance for any help. Ill be on here pretty regularly to reply if anyone has questions or needs clarification.

If you check the box and add $190.00 to the cost they will internally balance the rotating assembly.
Mike

 

[bm73charger]

Yeah i saw that, and i got some feedback on another post where a guy mentioned that i would need it internally balanced as its no longer a 360 crank, which makes sense to me. And then i would need as neutral balanced dampener and flex plate with a 360 converter and i would be good. Does that sound accurate? To me it sounds good but im a tad out of my depth there.

 

[RemCharger]

Yes an aftermarket balancer and b&m flexplate would be good. Internal balance.
Now the converter.. you can't use a "360" converter in your 904, chrysler didn't make 360/904s. Get a 727, and your converter choices are endless. ( they didn't put 904s behind 340s either)

 

[bm73charger]

Any recs on a converter for the 904?

 

[R413]

I had a 1978 fury wagon with a 360 2bbl and a 904. Thought it was odd but it was all there and running smooth.

360 converters have balance weights on them. Similar to 400's and cast crank 440's.

If you engine is internally balanced then you use a neutral balance converter.

 

[bm73charger]

how would i find that? Are converters for engines or transmissions? do i look for a 360 neutral converter. or do i look for a 904 neutral converter? or are they both? do i need a 360 to 904 nutral converter? any ideas on a flex pate? if i need one or not. if i do does it need to be neutral or weighted? any help is appreciated.

 

[RemCharger]

If you're staying with the 904, you need a 904 converter. With no weights welded on. And a regular 904 flex plate. If you have no concern about power handling capabilities.

 

[R413]

As stated, 360, 400 and cast crank 440's have weighted converters.

Your internally balanced stroker doesn't need a weighted converter.

So drop the "360 converter" term.

904 amd 727 have different converters, they will not interchange.

You will want a neutral balance 904 converter.

 

[493 Mike]

Built properly, a 904 will handle a lot of horsepower/torque.
Mike

 

[Curiousyellow71]

If your car had a 318 with a 904 you could reuse the convertor w your stroker if its not to wild.
Yes...you could get a better convertor. As you get up in hp on the 904 the convertor gets split at the pump drive ears. I would be guessing at the hp when those fail but we have run 904 behind a turbocharger 318 around 450hp and probably closer to 550 lb of torque. That transmission did have a shift kit. They are efficient little transmissions and the front drum is small enough it doesn't explode if it tears out the sprag. In our 65 dart 904 we have a convertor from Lenny at Ultimate, HD front pump drive upgrade from A&A, 175 psi race valve body from cope w low band apply, 5 clutch front drum and billet servo's. I would estimate it to handle near 600hp. But it will not live as long as a 727, that is the downside.

 

[1967coronet]

Hello all,

Im new here and in need of some assistance. I have a 73 charger with a 318 and a 904 transmission. I recently bought a 360 from marketplace that the guy says was from a 1990 d150. I have taken it to the machine shop and am getting it bored .030.

I want to put a stroker kit in it (Eagle 20502 SB Chrysler 360/408 Street Strip Rotating Assembly 10.0 Mahle Dish Pistons). This will be the first engine I have ever built but I have done plenty of tinkering and am fairly knowledgeable in most aspects. My questions are about installation and function. Do I need to buy the harmonic dampener and the flex plate with a 360 torque converter to mount it to the transmission. Or will I need to have it internally balanced, with no dampener and no flex plate just the 360 converter? I have been getting a lot of different opinions on it. Some people are saying the dampener and flex plate are only for the 360 not for a stroker kit and that the stroker kit will need to be internally balance. That the harmonic dampener and flex plate are only used to put the 360 in, not the stroker (408). And others are saying that Ill need a balancer and flex plate new torque converter and all.

I just need to know what I need to make sure it goes in smoothly and docent tear itself apart hahah. To me what makes the most sense is to get the crank internally balanced, and to mate that to my 904 with a 360 converter. Is there a reason thats a no go or is that the right train of thought?

Also any other tips and tricks to make this go smoothly would be greatly appreciated, along with any concerns to look out for which may become an issue.

Thanks in advance for any help. Ill be on here pretty regularly to reply if anyone has questions or needs clarification.

Just wanted to toss this in... if the machine shop has not yet bored your block hold off on the kit.
Wait till it's bored , sometimes. .030 turns into .040

 

[bm73charger]

Thank you for the advice. I want to stay 904 i think only because it eliminates buying a new transmission and driveshaft and figuring all that out as well. Ive heard they can hold decent power and this is not a super performance car. I want something that i can drive around comfortably in and still have some *** if i wanted lol. it will mostly be hanging out with a few car clubs who meet on weekends. But the block is at the shop now. Havent bought anything for it for the exact reason that i know things can change fast. Im waiting to get that home before i do anything else.