Getting ready to tear down the 340 in the 67 Barracuda and looking for a few pointers. This car most likely won't be run on the track just looking to build a strong street engine. Car is a 4pd setup with 3.23 Sure Grip/489 case. Before I pulled the engine I ran a cold cranking compression test on all cylinders. Numbers ranged from 168 to 172psi. It has been bored 0.030 as I can see stamp on pistons using bore scope but nothing else. Engine looks very clean, at least under the valve covers as there is absolutely no sign of sludge in that part. Clean as a whistle. It is a Nov 71 block with 72 4bl intake and manifolds. Heads appear to be 72 J heads. I don't know the current cam, piston, crank (Cast/Steel) or head specs but the heads, intake/exhaust manifolds are going to be swapped out along with rocker system.
I don't mind needing to run say 91 octane fuel as it's pretty common around here where I live in Oklahoma. Want to avoid abnormal detonation. Had a SBC 350 when I was a teenager that gave me fits in the summer time. Sometimes had to put it in 4th and drop the clutch to shut it off. It's CC psi was about 205. It does get a might warm in the summer here. We hit 106F ambient here last week. This won't be a daily driver and shouldn't be spun a lot unless we get a challenge and then guessing maybe ~ 6200.
Here is what I have in parts at this time.
235/60/14's on rear
Holley 770cfm Street Avenger Ultra
ProMaxx 171 Heads (65cc) 2.02/1.60
Edlebrock RPM Airgap Intake
PRW roller tip rocker system
Been looking at the COMP XE274H
230/236 @ 0.050"
Lift Int: 0.325
Lift Exh: 0327
Using 1.5 ratio rockers
LSA: 110
ICL: 106
IVC: 63
Nothing definite on the cam until I can get into the engine and check piston location at TDC, see if flat, dish or dome and get some info off the end of the cam. Hopefully grind # may be there?
All that being said, any of you folks have any good SCR/DCR numbers to shoot for on a strong street build to avoid ping/knock with 91oct without need to fiddle -/+ timing? Also good cylinder pressure to shoot for? My thoughts on HP and TQ were in the neighborhood of 425 or so HP and 400 lb-ft TQ out of it. Is that doable and not be a pain to drive on the street in a 340 or out of the question?
Sure I have probably left out some important information but will supply if I have it.
