Re: header tube size
 

Wow, Wade you sound like a real header builder......lol...but you forgot to tell him about the steps in the header and what purpose they serve....

1.625 is the way to go and when you measure that exhaust port, I bet it is really close to that size.....

Chassis1

Re: header tube size
 

Myron, agree but cut the collector off and put on Mark Lelchook's merge collector. Think you'll be very satisfied.

Re: header tube size
 

Lol, I've wasted enough money on headers and hardly ever see a gain. Use the KISS method.........

Wade O

Re: header tube size
 

for the combination you run, there are very interesting ways that are not simple to make the small engines move more air then ever thought. Believe it or not, it is done with the 4 into 1 and not the tri-y because of the cfm of the smaller heads......sometimes you can speed the air up too fast and the smaller engines do not like it.....

Chassis1

Re: header tube size
 

Thank you for the feed back gentlemen, I was pretty well sold on 1 5/8 to 1 3/4 tube size, based on what I had observed around the pits, that apeared to be the most popular small block set up. I will let the manufacturer sell me on collector style. Happy Holidays to all of you.

Re: header tube size
 

;)

Re: header tube size
 

Here is what we got; 360 motor wedge 1 5/8 to 1 3/4 to 1 7/8 with merge collector, 370 motor hemi; same size one runs to 7k, the other past 8k, the 370 liked a 1 3/4 to 1 7/8 about 5 better one made 540, one made 660.

Re: header tube size
 

Strangely, mine doesn't appear to like step headers. Been running them (1 3/4" to 1 7/8") since last year, but I have never even had the thing on a dyno until recently. Bought them on the recomendation of someone I really respect. The step headers only appear to help down around 5000 RPM. Past that straight 1 7/8" picked it up everywhere. If I were foot braking they might be worth more. Wonder what I'm doing wrong, that it doesn't appear to like them, when everybody else runs them?

Thinking about trying a set of 2" primaries? My old, original-1975-rules-292" C/SM Camaro loved 2" headers. But, it was a stick car leaving over 8000. This is a 358" LT1 trans brake car, the converter hits about 6000.

Re: header tube size
 

1.750 is way too big for the lt1 first step.......measure the ports one of the heads, I think they are more D shaped and barely over an 1.500.....

and remember, just because it is a step header does not mean the steps are correct......

Chassis1

Re: header tube size
 

The 1 7/8" are even bigger, yet made more power 5500 + up.