Which headers?

[Hog]

These headers on Tepepmeie's 703hp 427 LT5 are the best appearing headers for the LT5.
Quote from said member I believe they are ex-Baker racing headers from the road racing program in the 90's. Had them re-coated this year. 2 in. primaries / 28 in. long. They fit in a C4, I had them in my 91 previously. Torque is improved over the standard Watson/Jeals.

These headers supported 703 on the engine dyno, or 640 rwhp on the chassis dyno,corrected.







These headers would provide for power increases in a narrow rpm band because of their equal length, or near equal length primaries, the other headers I have seen have unequal length primaries lending themselves to a more broad power band.
I could be argued that unequal length headers could be better for a street car, and vice-versa. Certainly ANY sort of tubular exhaust header is better than the stock manifolds.

I would love to see some video so we could here the idle of that car once he gets her all tuned up. Heck even untuned, I love to hear a clip.


Stainless Works LT5 headers (both)


OBX LT5 header


Here is a Jeal header



peace
Hog

[FU]

Lovin those 2" primary's !!

[Karl]

Thank you for the welcome.

Originally Posted by Schrade

Welcome onto the boards there...

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What work do you have in your top end there, boosted, to get the extra twist in the rear wheels???



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and is header wrap beneficial?

With no portwork up top (yet), and exhaust gases not pushing capacity, the gases would cool quickly, and cooler gases are heavieir to push out the back...

[USAFPILOT]

Originally Posted by Hog

These headers on Tepepmeie's 703hp 427 LT5 are the best appearing headers for the LT5.
Quote from said member I believe they are ex-Baker racing headers from the road racing program in the 90's. Had them re-coated this year. 2 in. primaries / 28 in. long. They fit in a C4, I had them in my 91 previously. Torque is improved over the standard Watson/Jeals.

These headers supported 703 on the engine dyno, or 640 rwhp on the chassis dyno,corrected.







These headers would provide for power increases in a narrow rpm band because of their equal length, or near equal length primaries, the other headers I have seen have unequal length primaries lending themselves to a more broad power band.
I could be argued that unequal length headers could be better for a street car, and vice-versa. Certainly ANY sort of tubular exhaust header is better than the stock manifolds.

I would love to see some video so we could here the idle of that car once he gets her all tuned up. Heck even untuned, I love to hear a clip.


Stainlkess Works LT5 headers



Here is a Jeal header


OBX LT5 header


peace
Hog

my SW headers are the longer version than those depicted.

[USAFPILOT]

http://www.stainlessworks.net/produc...5-headers.html they will set them up for the air system if you want to pay extra, I did. If I could go back I would just ditch the air system, but I wanted to retain the emissions equipment for resale if it ever became necessary.

[Hog]

Originally Posted by USAFPILOT

my SW headers are the longer version than those depicted.

I added a longer set as well, from Stainless Works.

peace
Hog

[Fully Vetted]

Originally Posted by Corbusa

Will Corey be at BG?

No, he will not.

[boostedmaxPSI]

Originally Posted by Schrade

Welcome onto the boards there...

-----------------------------

What work do you have in your top end there, boosted, to get the extra twist in the rear wheels???



------------------------------------

and is header wrap beneficial?

With no portwork up top (yet), and exhaust gases not pushing capacity, the gases would cool quickly, and cooler gases are heavieir to push out the back...

See post 37. I outline all that has been. Hope this helps.
http://zr1.net/forum/showthread.php?t=17214&page=4

[Schrade]

Originally Posted by Paul Workman

The 90 LT5 has the most to gain from porting the top end. The primary runners are 33mm compared to 34.5 (about) for the later 93s and up. Also, the primary injectors are sealed at the top of the injector instead of at the bottom. This allows you to remove ALL of the shroud on the primary side injectors -making the 90 IH thee ideal year for top end porting.

The starting point for most top end porting is approx. 36mm. There are nuances that improve over that (but Pete n Marc each have dibbs on one of my family jewels, should I divulge a sacred FBI secret)

As far as port matching into the heads, I believe there is merit to tapering the port all the way down to the valve guide. But, there is some real concern for "punching through" if you don't have a road map, and pulling the head(s) means pulling the motor...not a cheap or easy thing to do.

P.

This I do not understand; NOT an O-ring seal at the top and bottom??? At the fuel rail, and at the port inlet?

Does FSM have a pic of the setup? Anybody got a snappic here? I suppose I'll see it when I get there, if ever....................

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And what's the definition of 'tubular' headers? As opposed to ? headers?

[efnfast]

Schrade, tubular headers are made with tubes as opossed to well, I don't know. maybe someone tried making them out of square stock, or flat stock (wouldn't flow very well).