Hi All,

Does anyone have any documented comparisons (Dyno runs) or even opinons on ported vrs non ported intakes. What I am running is a 68 L-78 396. The engine is completely stock except for headers and a MSD distributer. I have 2 intakes for this engine one has been ported to the same size as the stock 3919840 heads and the other is untouched. The intakes are both part # 3933163. When comparing the intake ports there is about a 1/4 inch difference in the port size between the 2 intakes.
I put it on a chassis dyno with the non ported intake and it made 334 horsepower and 490 ft pounds of torque at the rear wheels.
I have been wanting to try the Ported intake but it has a small crack that needs to be welded before I can.
Anybody have any thoughts on if the car will gain or loose anything with the switch. I ran the car last week and it ran 13.20 @103 though the exhaust and on street tires at 5300 elevation.
Thanks in advance,
Nick

On horse power tv they did a dyno comparison between porting the intake and pocket porting the heads. I don't recall the figures, but intake porting gave something like 2% and pocket porting of the heads gave something like 5 or 8%. In summary, it wasn't hardly worth the effort to port the intake.

-dnult

dnult,
Thanks for the info. So I guess it would be worth 6 or 7 horsepower in my case. not really anything to get all excited about but since I allready have the the intake I guess I should go ahead and use it. I am getting it welded right now and hopefully will have it back by the weekend. I have had a few friends tell me there might be 20 horses in that intake vrs the one I have on there. I kinda thought that was a little high but didn't know for sure.
Anyone else have any thoughts?
Thanks again,
Nick

I wouldnt see why not. Going from a stock intake to a newer/better designed intake will work wonders smile.gif

Originally posted by Daytona Yellow 69 Z/28:
dnult,
...So I guess it would be worth 6 or 7 horsepower in my case. not really anything to get all excited about...
Nick Just keep in mind that improvements compound. 6 or 7 HP with a stock manifold might turn into an improvement of 10 to 12 HP (porting alone) with a new intake. The intake would add more on top of that. Get my drift? In other words, that 6 or 7 Hp will grow along with other improvements in VE down the road.

-dnult

First, the intake isnt ported, it sounds to me like its just "port matched", since it
doesnt have plenum work or runner work. If this is the case then the power
gain would be next to nothing - I'd say around 5hp, and thats if its matched to the
heads - ports line up. So I dont think its worth the trouble. Now if it was ported, it
could be worth from 10-30+hp, depending on the intake and amount of work.

67Rs502,
Yes, i should have given a better description of the intake. It is portmatched, However the differance between the two intakes is like night and day. The port matching is most if not all the way up the runners.
Thanks again,
Nick