Optimal Header design for 484 FE without shock towers.

[900HP]

What does everyone familiar with the FPA-Tri-Y headers think would happen if I was to take my set and modify them with a longer tube straight off of the head flange and then a gradual curve into the existing header, thereby eliminating the tight turn normally there for fitment in cars with shock towers? Would they be adequate for my engine combo?

Barry tried both my FPA's and his Dyno Header on my engine and the results are as follows:

FPA's=540HP@5600,  547TQ@4900

Dyno=553HP@5600,  555TQ@4900

I looked on FPA's website and I can see why they are down on power to the dyno headers, what an awful design.  You are not going to pick up large amounts of power with a header change.  Building the correct header you will make more power everywhere but you aren't going to pick up 50hp.  REAL 4-2-1 headers should look like this:


Or this:

[ScotiaFE]

If you have all this really high end gear and cut the towers out of the Lane
why would you buy what some would consider the crappiest pipes out there.
Even an old set of Hookers would help here.
REF makes some pretty nice Lane pipes also. Those SS guys can get up on it.

Nice looking pipe Mark.
How much? 

[hrtatk1]

Mark,
What would you charge to build a set of headers for this combo?  Looks like you use Stainless? Do you wrap them to reduce engine compartment heat? What do you wrap them with?
Thanks, josh

[900HP]

Mark,
What would you charge to build a set of headers for this combo?  Looks like you use Stainless? Do you wrap them to reduce engine compartment heat? What do you wrap them with?
Thanks, josh

You probably don't want to go down the route of custom stainless headers as the cost vs. benefit for a street car just isn't there.  It's a whole other story if you are class racing or have a car that you simply can't buy headers for.

That being said for a set of custom stainless 4-2-1 headers be prepared to spend $3500 parts and labor.  I wouldn't wrap them, it just decreases tube life, even with stainless.  If it was a turbo car with lots of heat you'd use 321 or Inconel and wrap them at that point.

[hrtatk1]

Mark,
Since my heads have rectangular exhaust ports which measure 1.375  X  1.937, would there be any benefit to running rectangular tube a certain distance before transitioning to a round tube or are you better to transition to round immediately?
Based on the exhaust port size would you use the slightly larger 1-7/8" or smaller 1-3/4" or do you use thicker wall 1-7/8" to get area similar until first step?

[garyv]

Josh,
Unless you can build these headers yourself or have $4K to spend on a custom made set, your best bet
is to call REF and have them make your headers.
At the HP level you are at REF's will be more than adequate for what you need
I talked with them and they built the headers for my 465 TP that's right at 700HP now and will be over that when completed.
It's on the next page of this forum and you can read about it if you want.
my 2 cents
garyv

[ScotiaFE]

Not sure if these are the "Optimal"
but they look great.
And they obviously worked pretty good.

 

[jayb]

Those are cool, are they from back in the day Howie?  Like '68 or '69?

[ScotiaFE]

Yes they where the headers for the 68 Torino that David won the Championship with.
The 68 cars had a "non stock" front clip.

[900HP]

Mark,
Since my heads have rectangular exhaust ports which measure 1.375  X  1.937, would there be any benefit to running rectangular tube a certain distance before transitioning to a round tube or are you better to transition to round immediately?
Based on the exhaust port size would you use the slightly larger 1-7/8" or smaller 1-3/4" or do you use thicker wall 1-7/8" to get area similar until first step?

The area of 18gauge 1.875" (1 7/8") tube is going to be really close to your port after you subtract the area of your corner radius.  For STREET use I would do 1 3/4" step to 1 7/8" primary tube.  For RACING use I would do 1 7/8" no-step or possibly 1 7/8" step to 2" even though that's getting on the big side.  Keep the collector at 3" though.