72 Duster 400B
- Thread starter timmy
- Start date
-
Hey Timmy and welcome aboard!
I did exactly this myself. A '78 - 400 into a '71 Duster.
The following tips can be done for cheap HP but of course, cheap and BP (gains) are all relative. From top to bottom of the engine;
Open air cleaner. I suggest a min. Of a 12 inch diameter 14 is a common size and 2-1/2 thick.
The stock TQ carb is a good street strip carb. The smog unit you have now will do fine for what you have. The bennifit is it rated at 850cfm.
The intake is a little restrictive but not so bad ethier.
Moving away from the OE carb and intake, IMO, a nice intake would be the RPM a d a 750 carb. Holley or Edelbrock.
The next thing is the heads. A milling of the heads to help the very low compression ratio (which is under 8-1) would be good. Once you mill the heads, the intake might have to be milled in order for it to fit. This is not a huge difficult thing to do.
The cam shaft! The brains of the operation!nTake some time with this one because of the low compression and short stroke, over caming is an easy thing to do. We'll discuss this later as it is part of the overall plan which needs to be thought about first.
Consider it a target to aim for. Get the proper valve springs for the cam from the cam manufacturer.
With that min mind, cam, we can go back to the heads. The cam and heads have to work nicely together (as well as the rest of the engine parts) The head work can be decided from here.
Headers: I followed instructions from BigBlockDart.com on how to use "B" body headers in an "A" body car. They worked well. A set of used B body standard headers require a few good hammer swings. Otherwise, the choice of headers and there prices will be few and expensive though worth the price.
Use a 2-1/2 inch exhaust system. You can get it from Summit racing or Jegs complete for under $250. Some minor cutting will be needed and it is no big deal.
All that is left is a good gear ratio, stall converter if need be and some suspension parts and wide tries.
I myself used a Holley Street Dominator with a TQ and the Bbody headers so far. Not much else to report.
I did exactly this myself. A '78 - 400 into a '71 Duster.
The following tips can be done for cheap HP but of course, cheap and BP (gains) are all relative. From top to bottom of the engine;
Open air cleaner. I suggest a min. Of a 12 inch diameter 14 is a common size and 2-1/2 thick.
The stock TQ carb is a good street strip carb. The smog unit you have now will do fine for what you have. The bennifit is it rated at 850cfm.
The intake is a little restrictive but not so bad ethier.
Moving away from the OE carb and intake, IMO, a nice intake would be the RPM a d a 750 carb. Holley or Edelbrock.
The next thing is the heads. A milling of the heads to help the very low compression ratio (which is under 8-1) would be good. Once you mill the heads, the intake might have to be milled in order for it to fit. This is not a huge difficult thing to do.
The cam shaft! The brains of the operation!nTake some time with this one because of the low compression and short stroke, over caming is an easy thing to do. We'll discuss this later as it is part of the overall plan which needs to be thought about first.
Consider it a target to aim for. Get the proper valve springs for the cam from the cam manufacturer.
With that min mind, cam, we can go back to the heads. The cam and heads have to work nicely together (as well as the rest of the engine parts) The head work can be decided from here.
Headers: I followed instructions from BigBlockDart.com on how to use "B" body headers in an "A" body car. They worked well. A set of used B body standard headers require a few good hammer swings. Otherwise, the choice of headers and there prices will be few and expensive though worth the price.
Use a 2-1/2 inch exhaust system. You can get it from Summit racing or Jegs complete for under $250. Some minor cutting will be needed and it is no big deal.
All that is left is a good gear ratio, stall converter if need be and some suspension parts and wide tries.
I myself used a Holley Street Dominator with a TQ and the Bbody headers so far. Not much else to report.
I really apriciate your advice guys. I have a edelbrock rpm mani and a 650 carb so I'm headed in the right direction I'm gonna get the b body headers cause there about 300 bucks cheaper. What would you suggest for cooling?
1969VADart
Well-Known Member
Welcome from Virginia. Good luck with the build.
-
