Choosing a converter has me pulling my hairs.

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340Dust-her

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Long story short. The cam was replaced on my 68' 340 with some purple cam, don't know the duration. Upon rebuilding the 904 they installed a rebuilt 2500 stall converter(cheapo). Let's just say it was a wrong setup. In about a month I plan on getting the 340 rebuilt(stock stroke and bore). I heard great things about this cam(Lunati 60403) which I may use along with a dual spring setup. Can anyone help recommend a converter? I heard Hughes is an excellent product. This is a street car that will see the dragstrip on occassion. 904 transmission, 3:55 gears and 255/60r15 tires out back(3100lb weight). Thanks in advance.
 
If you get a Hughes make sure you get one rated at a higher stall than you think you need by about 3-400 rpm as they seem to be on the tight side.

I personally prefer PTC over Hughes but that's just my preference.

With that cam you'll need about 2700-3000 stall to make it scream good on take off. I am running the Lunati 60404 in a 360 with 68 X heads and have a PTC 3000 converter and it is just about perfect for street use.
 
I think the cam that was replaced was a high lift long duration, calling for a higher stall speed? It just turned out to be a wrong combo. Since the motor is coming out I want to throw in a quality right converter and be happy.

Thanks fishy, I will look into them. For a904 I'm assuming there's only a 10"?
 
fishy68 said:
If you get a Hughes make sure you get one rated at a higher stall than you think you need by about 3-400 rpm as they seem to be on the tight side.

I personally prefer PTC over Hughes but that's just my preference.

With that cam you'll need about 2700-3000 stall to make it scream good on take off. I am running the Lunati 60404 in a 360 with 68 X heads and have a PTC 3000 converter and it is just about perfect for street use.
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PTC and Coan are both Excellent pieces. But with 3:55 gears. you need at least 3:91. Jmo
 
I've got that same cam in my 340, and have 3.91 rear gears.
Yesterday, I ordered a converter from CRT. After talking with John Cope, I settled on a converter with a 2800 to 3000 stall.
 
Being a 4spd guy, IF I was to do this once and right the first time around and never wanna open anything back up again, I'd call a pro. Dynamic converters has a excellent rep. He does a lot of racers and hot rods.
PTC seems to have a good rep here.
 
Yeah I just emailed them(PTC). :) I was hoping to stay with 3:55's for the time being. I can upgrade the ratio possibly next year. But 3000 stall seems the best bet with the cam. Think it can work with 3:55 for the time being?
 
340Dust-her said:
I think the cam that was replaced was a high lift long duration, calling for a higher stall speed? It just turned out to be a wrong combo. Since the motor is coming out I want to throw in a quality right converter and be happy.

Thanks fishy, I will look into them. For a904 I'm assuming there's only a 10"?
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I was running an 11" PTC 3000 stall behind my 360/904 combo. Thing screamed. Moving to a 4 speed which is the reason for the "was." I'd definitely go with PTC again if I ever have an auto car again. The cam in my 360 is a comp XE275HL. It's a .525 lift......can't remember the duration......something like 231/237 at .050? maybe? anyway, the guy's at PTC talked to me about the car, it's purpose, gears, tire height and motor specs. Then sent me exactly what I needed. They were great to work with!
 
I just got my 11" 2800 stall from PTC, this is my 3rd. converter from them in the past 4 yrs., accually the 4th., had them currect a TCI that was a slippery mess, these guys are great, there prices fit the quality 10 fold, i paid 275.00 for mine this last round, & all there converters now come with a balloon plate if you ever run nitrous, my 1st. converter with them was an 11" with a 3000 flash stall for my 451, it felt stock, but put my car in the 1.57/1.58 60fts., now thats pretty amazing for an 11", i was out about 250.00 back then, if you don't mind spending around 375.00, this will put you in a 9.5", this way you can set it up alittle tight for now (around 3200), but if ever choose to want more, just send it in for a small price, all you get from the 11" is 3000 max.

I would also look into going with at least a 3.91 gear, maybe 4.10s.

BTW, Cope's converters are PTCs.
 
340dust-her,that 60403 an excellent cam i used it for a season in my 416 when i first put it together,with great results..as for a converter,i use no one else but Lenny at Ultimate Converters give him a call,he'll treat you right and built ya' one badass converter..:-D:-D
 
340Dust-her said:
Yeah I just emailed them(PTC). :) I was hoping to stay with 3:55's for the time being. I can upgrade the ratio possibly next year. But 3000 stall seems the best bet with the cam. Think it can work with 3:55 for the time being?
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3.55s will be fine unless your looking to race the car and get every tenth out of it,and with a good convertor you can have around a 3k flash stall and it will still be tight driving around town.The start ratio with 3.55s will be 8.7 which isnt terrible,with 3.91s it would be 9.6,about 10.1 is ideal for a street car.I like to run the low first gear in the 904 which gives you the start ratio of 3.91s without the rpms on the freeway.
 
Depending on your main purpose for the car 3:55 gears might do you fine. That's what I have in my Cuda now with 28" tires so it's a very mild cruiser down the hwy but yet it still runs decent. Of course it's not as quick as the 4:10's it had but we like to go to alot of cruise-ins and some are as far as 50 miles away so the 3:55's are naturally much better for those drives. I ran 12.91 with the 4:10's and it ran 13.56 with the 3:55's and that was on a bad tune. Since then I got it running much stronger and think it'd be in the 13.30 range. This with a mild 360.

I think your right that 904's start at 10" converters with PTC.
 
got a buddy that owns a trans shop not to far from Hughes, he will not even consider using one of there convertors. never very specific about why, mumbled crappy quality, hesitant to stand behind there product among other things. he has been using a shop in Lake Havasu City, I think it is called TCS. I have one of his t/c in my Duramax, the triple disc stainless unit. the thing is incredible. I do know that Doug has used him for all of his off road racing units with great success....
 
I'll never use Hughes again. I talked to them gave them all my specs and they sent me a converter, a 9.5". It was pretty loose for a 9.5 converter. I kept thinking the car should run better than it did. Anyway to make a long story short I called Paul Forte at TurboAction and talked to him. He sent me an 8" and my car picked up 7 tenths. That's a huge amount.
 
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