A Few Questions

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DARTLARRY

DARTLARRY

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I Have A Stock 71 360 With J Heads. Ld340 Intake, 625 Carter, 455 Purpleshaft With Stock Rockers And Springs. And A Cheap Set Of Headers. My Questions Are What Can I Do To Get More Power, Is There A Way To Up Compression Without Changing Pistons, Should I Try A New Intake That Would Flow Better. I Was Looking At Hughes Musclecar Cams Also, Maybe Port The Heads A Little. Oh By The Way Did I Mention That I Am On A Budget.
Any Suggestions Are Very Appreciated
 
what is it running now and how do you want it to run?? bigger cam, bigger carb, maybe bigger convetere , more gear ... theres allot you can do but we need more details of what you have and what you want...
 
Im Not Racing This Thing. Its A 71 Dart With 727, Stock Converter. 83/4 With 391 Gears. I Just Want A Quick Street Car. Dont Get Me Wrong Its Fast Now. But Just Looking For Better Performance. I Hope I Covered Everything.
 
If you don't have any detonation problems now, you could probably cut .030 off of the heads. Your intake should be good for your application.
 
Well, you don't have to worry about the intake! On the street, you definitely want a dual plane and the LD340 is one of the best ones.

Milling the heads would be the easiest way to up compression. With OEM pistons, you have less than is advertised. But then you may get into lifter preload issues. It can be a little difficult, but adjustable rockers & pushrods, which will likely have closer to the advertised 1.5-1 ratio, will compensate and help lift a bit. You will have to get shorter pushrods (About 7.23") to use with your hydraulic lifters. 273's with adj. rockers all had solid lifters with longer pushrods.

Very mild porting, focusing on opening up the valve pockets would be most cost effective.

A vacuum secondary Holley 750 (3310) may be easier to tune and provide a little more airflow. A 4-hole spacer wouldn't hurt.

You shouldn't go too wild on the cam with a conservative gear and converter. The low compression you're stuck with is another reason.

A 904 trans built to the same level as a 727 with the same spec converter is about .15 faster in the 1/4 mile. A good valve body or shift kit will help either trans live with OEM pieces. Aux. cooler is a good idea.

Nail head valves will flow a little more on the intakes than the OEM tulip-style.
The stainless replacements usually have less of a "pocket" on the chamber side which will help compression a tiny bit.
 
A zero deck piston will do ya well. An example would be a KB107. Note the deck of the block may have to be milled to get a true zero deck. This would make it very close to a 9.8-1 ratio. Not to great for 93 octane and a small cam.
A slightly thicker gasket like a Fel-Pro thats .054 rather than the .039 will help keep the ratio pump gas freindly.

About cams, I would look at a split duration cam in the duration that equals your cruise speed. Look at these web sites;
http://cranecams.com/
For some reason, this site has there default page up. it'll still work.
http://www.compcams.com/DefaultWide.asp
And of course Huges cams also has the intended useage, rpm range and best parts to use with there cam for best results.

From there, you can make a good choice on a cam. Worst case, ask the pro's.

I also would think about a higher more efficent convert than ave. joe's converter shop down the block. A good converter will not cause big drivabilt problems.

After that, Listen to Locomotion. I know he knows what it takes.
Your intake is excellent. Don't be fooled into a new one.
 
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