I need advice on engine rebuild

[mr440]

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I need some help, Firstly, here is an attatchment of my engine details, I aim to rebuid it in the winter, It was last done 12 years ago and is getting a bit lazy, I have a stock converter and a 727 box and a 3.23 rear end, the best time i have run so far is a 14.7. I would like to get under the 14. Now do i stick with a purple shaft cam with the same lift or do i change to a different one, do i need a higher stall speed converter, would changing the 750cfm Holley for a  Edlebrock 800cfm make it any better

[andy74]

there are better cams out now days,firefighter ron usually has good advice,or chryco-id get a 3.55,and a 2500 stall,should help your quarter times,and maybe a little more aggressive cam 

[deputycrawford]

I tend to agree.    If you look into an Engle cam or something else newer in technology, you can stay with the same duration, have a wider lobe separation for a wider power band, and have higher lift. Go with the 3.55 and a 2500 ish stall. The car will have the same manners and have more power everywhere.

[mr440]

Any more input would be good.

[Challenger340]

In response to you're "going to rebuild it this winter", I'm wondering how involved you want to get with the engine ? I'm assuming a basic cleanup and re-ring ?

Without knowing more specifics in regards to the "Mopar cast aluminum Pistons" ie; actual Compression distance, or "how far down the hole" they are, it's tough to make much more than just general rec's ?

As stated, if you just want to go faster in the 1/4, add gears and a convertor, that'll drop the 60 ft times substantially, which anything you gain 60 ft timewise, you can double it, and subtract it from expected overall E.T. reduction.
Example; if you're currently getting 2.0, 60' times on a 14.7 pass, and  a well matched gear and convertor combo resulted in 1.8 , 60' times, you can probably look at a E.T. reduction in the 1/4 of  "2" X .2 = .4 faster, albeit same theoretical, and probable MPH, on the same "untouched" engine, but the pass would drop to a 14.3.

Some areas I think you may want to check, and correct while you have the engine apart this winter;

Add Good rod bolts, if not already there, be sure to resize the rods again if you're adding them.
Get some head work done, Bowl Porting, backcut Valves, milling.
Better camshaft, I'm sure Firefighter3931, or Chryco, will rec some good ones they've used.

Headers ? Good distributor curve and hot spark ? Tuning on your 750 Holley ? I'm assuming it's a 3310 Vac. secondary ? Street Dom Intake ? 3,000 stall ? .484" mopar cam ? 3.55:1 rear W/27" tire ?
Just some thoughts, endless possibilites. I just mentioned the 3,000 stall because I suspect you're low on compression with those pistons, and you may want to "cover" the bottom number, for good 60 ft times, on whatever cam you decide upon.

Just my thoughts,

Come on guys, chime in here with some ideas and thoughts

[Challenger340]

Apologies !
just re-read your engine detail sheet, saw you have '67 915 closed chamber heads. You're probably not THAT low on compression afterall.  You still may want to check actual compression by CC'ing while apart, just helps cam and convertor selection.
9.5:1 would be nicer though !