Just installed a budget rebuilt 72 340 in my 67 dart. First time ever rebuilding an engine. It sounds great and runs pretty smooth, but it does not have the grunt I was expecting. Please help me tweak it. Here are the details of the rebuild -
.030 over 72 block with stock "J" heads 1.88/1.60 (did not do a valve job, just cleaned everything up).
New pistons and rings - silvolite 10.2:1 compression, but since they're being used with the lower compression 72 heads, I'm only getting about 9.4:1
If you used the 72 type pistons, you have about 8.1. They were 4 eyebrow pieces. The heads were the same except valve size. The compression difference was made with the pistons, not the heads. The early 68-71 340 had 2 eyebrow flat tops. The 72-73 engines had 4 eyebrows with a large trough that dropped compression drastically to about the 8.1 range. Unless you used the early style 2 eyebrow flat tops, you have much less than 10.2.
Cam is 280/480, 110 deg (I think)
Cast iron manifolds with 2 1/2" exhaust and flowmasters
Headers would help you tremendously. The manifolds are holding you back greatly.
Edelbrock RPM Air Gap and 600 cfm Edelbrock carb
Not a bad choice.
Still running points distributor, about 12 degrees advanced.
As mentioned, probably not enough, especially if you used the later piston style.
It's connected to a 904 with a shift kit and the torque converter only stalls at about 2300 RPM. 8 3/4 rearend with 3.91 sure grip.
That's not much above stock. Stock was about 1700 and the factory high stall was about 1000 more.
This engine should be somewhat of a screamer, correct? I'm dissapointed with it's performance. Help!
