supercharged 340

[Joller]

Hello everybody. I came to this site to ask a some advice for building my car. I have -67 Dart GT with 340 engine and a 727(this particular one has brought me nothing but trouble) transmission, and I also have a dyer´s 6/71 blower, Edelbrock cylinderheads and the pistons are made by Venolia. So obviously I´m going to supercharge it and I would need to know how much can the 340 block handle, because it needs to produce around 600-700 horsepower and boost is going to be somewhere around 17-19 psi, so what do I need to do to the engine so that it will handle this kind of torturing, and what part manufacturers would you recommend? And the second question would be that I also have a A-833 manual transmission to replace the 727, how much power can it handle when it is in stock form? And what clutch manufacturer makes parts that would work well with my aplication? And the final question would be that is there a manufacturer who makes new shifters and linkages for the A-833 and A-body? I also have to apologise for my bad english, I am from Finland so english isnt my mother tongue and it might be a bit hard to make anything out of it, but let´s hope that someone can understand my writing.

[turbokid]

I would look at a, e, and bbody for your shifter. The la motors can handle pretty much anything you can throw at them. The a833 is a good transmission and should also hold power just fine.
I would suggest Mopar Style or Untitled Document as they are more muscle car and vintage Mopar oriented.
Q

[90vntShadow]

Your motor should do fine with the factory forged crank and heavy duty rods with forged pistons. The 4 speed tranny is pretty much indestructable, I had one in my 71 roadrunner
383 pushing around 400hp no problem. Also had a 4 speed in my 73 340 Challenger putting out around 400hp. I used a Centerforce dual friction clutch on both cars. Here are a few pics of my cars, should have never sold them.
Oh well, they are a lot of work.

[86trbolancer]

90vntShadow: wow nice piece of work!!! yeah you shouldn't have sold those

[turbokid]

Our 69 charger is running around 500 on an auto and the other 3 muscle cars my dadhas all run automatics unfortunately. But my buddy in mn has a 550-600 hp 66 hemi charger that is running a 4 speed with no issues.
Yes very nice car by the way.

[Lunyfringe]

Quote:

Originally Posted by turbokid Our 69 charger is running around 500 on an auto and the other 3 muscle cars my dadhas all run automatics unfortunately. But my buddy in mn has a 550-600 hp 66 hemi charger that is running a 4 speed with no issues. Yes very nice car by the way.

you guys are killing me- gotta make time to fix up my '68 Charger...

I'm thinking twin turbos (since I'm around 6000' above sea level)

[ButchSuppe]

Quote:

Originally Posted by Lunyfringe you guys are killing me- gotta make time to fix up my '68 Charger... I'm thinking twin turbos (since I'm around 6000' above sea level)

68 Charger THE BEST LOOKING OF ALL CHARGERS.

[Joller]

Ok.Thanks for all of you. Now I quess I have to start finding the right parts for it, does anyone have any experience about engine components made by Eagle or Scat? And what camshaft manufacturer would be good? I was thinking about hydraulic roller cam from Lunati or Comp cams and roller rockers from crane cams with 1.6 ratio..

[Joller]

Oh and I almost forgot to say that the roadrunner and the challenger are both very nice..

[90vntShadow]

Quote:

Originally Posted by Joller Oh and I almost forgot to say that the roadrunner and the challenger are both very nice..

Thank you. Eagle and Scat are both good. What are you looking at that is Scat? you should already have a forged crank. Not sure about what cam you should run with a blower, also you will want to run lower compression like
around 7:5 or 7 to 1. You will have to do a little more research on that, that will also determine what pistons to use, dished or relocated wrist pin for the lower compression. You might have a harder time finding those kind of parts for you application since it is a Mopar and more $$$$$$. I had over $5000 in the roadrunner drivetrain and that was over 10yrs ago.

[Joller]

Quote:

Originally Posted by 90vntShadow Thank you. Eagle and Scat are both good. What are you looking at that is Scat? you should already have a forged crank. Not sure about what cam you should run with a blower, also you will want to run lower compression like around 7:5 or 7 to 1. You will have to do a little more research on that, that will also determine what pistons to use, dished or relocated wrist pin for the lower compression. You might have a harder time finding those kind of parts for you application since it is a Mopar and more $$$$$$. I had over $5000 in the roadrunner drivetrain and that was over 10yrs ago.

I was thinking about the Scat H-Beams, I have those Venolia Pistons and they are dished and with them the compression is 8.2:1 do you think I should drop it more or will it work like this? Guys at Dyers blowers told me in an email that I cant get it to work on the street with 15+ psi and I would need to run 116+ octane gas.. why is it so, because I havent seen an engine here in finland that would run so low boost level as under 11psi(exept for the original factory made vehicles) so I was thinking of what kind of gas do you use normally, the lowest octane number we get here is 95(and we also need to pay 1,64 USD for 0,264 US gallons of it(1,3euros for 1 litre)and the funniest thing is that it is quite cheap at the moment, it was over 1,5euros during summer).

[Tim_K]

About 7-8 years ago, I went to the Mopar Nationals in Columbus OH. On the saturday morning, I was walking around the hotel parking lots on Brice Road, and some guy had just put a fresh supercharged 340 in his Dart Sport / Duster. It was grey colored, I remember that.

This asshat had a severe case of diahhrea of the mouth, he was talking all big about it, how powerful and fast it was, etc. I just let him run his yap for a while, not really listening, but videotaping the engine bay. He thought that by quick revving the engine repeatedly, that would break it in enough to go racing at the track that day.

That night, I was walking around Brice Road again, and chucklehead had a big sign on the side of his truck - need bearings for a 340 crankshaft! He actually thought he was gonna change the bearings there in the parking lot and race again the next day!

I don't know what happened after that, never saw him again.

[90vntShadow]

Quote:

Originally Posted by Joller I was thinking about the Scat H-Beams, I have those Venolia Pistons and they are dished and with them the compression is 8.2:1 do you think I should drop it more or will it work like this? Guys at Dyers blowers told me in an email that I cant get it to work on the street with 15+ psi and I would need to run 116+ octane gas.. why is it so, because I havent seen an engine here in finland that would run so low boost level as under 11psi(exept for the original factory made vehicles) so I was thinking of what kind of gas do you use normally, the lowest octane number we get here is 95(and we also need to pay 1,64 USD for 0,264 US gallons of it(1,3euros for 1 litre)and the funniest thing is that it is quite cheap at the moment, it was over 1,5euros during summer).

If you are going to run 8.2:1 you could probably only run about 7-8psi on pump gas. 7.5:1 still probably only about 10-12psi that is a lot for a v-8.
Generally v8 guys run under or around 10psi not like a 4cyl. You would have to experiment see where you get detonation and definately run a good wideband Air fuel gauge. I am no expert on this matter but this is generally what I know from experience. Trust me that motor is a handful even with no boost running around 400hp, my Challenger was a low 13sec car in the 1/4 mile and you had to make sure you were pointing in a straight direction when you got on it or you would bring the car around in a hurry. That was running 3:91 gears, 8 3/4 rear end with posi traction. (Mopar limited slip clutch type).