318

[71chally416]

I haven't run my current car yet and all I have is the engine dyno numbers which don't mean anything, so I figured I would post up my last car engine first.

The last Mope I owned before the current Chally was a '68 Cuda that had a 8 to 1 compression (actually 7.9 to 1 when I checked it by CCing the chamber and cylinder bore) 318 with the .474" factory hyd cam and an old antique LD340 Intake with a Thermoquad. It had 340 heads off a '70 Duster that I ported myself (I have access to a flow bench and I port heads on the side for anyone interested) and some cheap 1 5/8" Blackjack headers. 904 tranny with the 2.74 low gear and a stock convertor with 4:30 gears. I always used regular gas, the cheapest I could find and it never pinged running the timing at 36* total. The best it ever did was 12.78 @ 109 with slicks and open headers and 13.0 through the muffs (2 1/2" homemade system with quiet mufflers) with 275/15 T/A radials. It was initially built as a "gas mileage" car but it ran so good I ended up racing it quite a bit. Here's an old vid of it running at Atco Raceway in Jersey.
http://streetwalker.homestead.com/files/68cuda1.wmv

[asm74]

 

[ViperMan]

Well, you piqued my curiosity, and judging from the history of your posts, it sure seems like you know what you're talking about!

Have you ported 440 heads before?  I'm going to be purchasing a set of new, aluminum heads in the near future and would like a solid, "mild" porting done to them.  I have a nearly indefinite time frame, so I'm looking for shops that I can ship or deliver to (I'm located in Pennsylvania - I see you're in NJ) and give them all the time they need to do the job properly and professionally.

Let's chat. 

Jeff

[71chally416]

Been doing porting for 25 years. Many sets of BB Mopar heads, especially the 906's. I had one customer that actually picked up 10mph with some 906 heads I ported. All his GM buddies said "it won't help" but they had nothing to say after he ran it.
I've also ported B-1 heads and some closed chamber 915's. They really had some horrendously bad valve pockets    That's good though, cause the worse they come from the factory the better the gain with some porting. I much prefer porting aluminum heads, of course. They are much easier. Let me know when you wanna do it. I'm working on some 302 SBF heads right now for a guy in OK but I should have them done by Friday. I can have them done in 2 weeks MAX from when I receive them. I do Intake manifold porting too.

[imean340]

Wow, thats a wicked time for a mild 318. That was in an E body? was it gutted or anything? Im hoping my 340 breaks into 12's with .480" lift cam, 4.56 rear, hooker supercomps 1 3/4's, eddy manfiold, lakewood drag shocks, 70/30 KYB adj in the front ect ect... but im not so sure it will. That port work sounds like it really woke it up.

[asm74]

Just to clarify, you had 7.9:1 compression after the head work?  How extreme was the porting job, and these were X heads? Totally stock block?

I have a 318 I'd like to build up myself.  I'm learning how to port on the stock heads now, and I'm interested in bumping the compression up to 9:1.

[71chally416]

Just to clarify, you had 7.9:1 compression after the head work?  How extreme was the porting job, and these were X heads? Totally stock block?

I have a 318 I'd like to build up myself.  I'm learning how to port on the stock heads now, and I'm interested in bumping the compression up to 9:1.

That's what the compression worked out to. The pistons were .080" down in the bore if I remember right. The heads were off a '70 Duster 340 with the 2.02 Valves. I also replaced the stock "Tulip" Intake valves with the "Nail head" valves Ed Hamburger used to sell. Mancini sells similar valves. They flow WAY better on the flow bench than the stockers. And it was what I would term a Stage II port job. I would charge about $500 to do a set that way. The valve guide bosses were reduced, the pockets and short side were all extensively blended and the Intake face was worked over with the pushrod pinch reduced. About 25 hrs work. I can tell you I had a real big smile the first time I ran through the gears with them on the car after swapping the 1.88 valve smog 340 heads I was using. The car went from 4,500 to 6,000 rpm twice as fast as before and would rev to 7,000 with ease.  Don't ever believe a 318 won't like better flowing heads than stock 340 heads. That's poppycock.

[71chally416]

Wow, thats a wicked time for a mild 318. That was in an E body? was it gutted or anything? Im hoping my 340 breaks into 12's with .480" lift cam, 4.56 rear, hooker supercomps 1 3/4's, eddy manfiold, lakewood drag shocks, 70/30 KYB adj in the front ect ect... but im not so sure it will. That port work sounds like it really woke it up.

It was in the '68 Cuda on the video above. It weighed 3,250 without driver. An E-body is a bit heavier, but with 20 more cubes, a bit more compression like 9/9.5 to 1 (It's unlikely most of you guys will be strapped with the blower pistons I had!) and a  better convertor it should be easy to do mid 12's in an E-body. ALL Mopar engines can benefit from head porting. Just consider a new 5.7 truck Hemi head flows 280cfm on the Intake side (300+ with just a little clean up porting under the valves) and the typical stock 1.88 valve 340 head flows 200cfm. No wonder those new Hemi's run so well!