New headers for C-4's
Thread Starter
Racer
Joined: Jun 2006
Posts: 361
Likes: 6
New headers for C-4's
Attached are pictures of prototype L-98 headers fabricated by Dyno Don from SoCalTPI.Org. I will fit them Monday and Dyno Don will tie them into the factory Y-pipe. We did a fitment test before the jig was finalized and they fit on both sides. I will dyno the car with the headers next Saturday the 19th and will post the results. I did dyno the car last year so we do have a base number to work from.
A second set is being fabricated as I write this and air tubes will go on both sets. I will post new pictures when the second set, with air tubes, comes back from the coaters. Unfortunately, the second set is spoken for by another C4 brother. I will keep you posted.
You can find threads on Dyno Don's work on Thirdgen.org.
Search for Dyno Don headers.
A second set is being fabricated as I write this and air tubes will go on both sets. I will post new pictures when the second set, with air tubes, comes back from the coaters. Unfortunately, the second set is spoken for by another C4 brother. I will keep you posted.
You can find threads on Dyno Don's work on Thirdgen.org.
Search for Dyno Don headers.
Racer
Joined: Oct 2007
Posts: 478
Likes: 1
I have my car over at Dyno Don's getting my new intake system installed. Anyways I got a chance to look at the prototype headers and they are awesome. They are a big improvement over the factory style. They are also large enough to clear the ports on the new AFR heads which is no small order as wide as the exhaust ports are on those heads are.
By the way with the motor in my 1989 Trans Am and a set if Dyno Don headers installed my motor engine dyno'd at 535hp so they do work.
By the way with the motor in my 1989 Trans Am and a set if Dyno Don headers installed my motor engine dyno'd at 535hp so they do work.
Thread Starter
Racer
Joined: Jun 2006
Posts: 361
Likes: 6
so...just by replacing your stock manifold, with something with a connecting bar between the mounting plate, a bit longer collector and a two bolt flange, you got 535 hp, and it goes thru the same exhaust...ya right. BTW those are called 'shorty' headers, they've been around since before you were born...probably.More BTW, dont see supporting vender...anywhere.
Don's been drag racing since the sixties and 89GTA has almost as many years. No crutes or fishes here sarge.
I believe his intent was let us know we have options for exhaust if these work out. My intent was to show off my new exhaust, as does everyone else here does when fabricating new parts. I apologize if it sounded like a plug.
Infantry leads the way!!!!!!! Happy Veterans Day!!!!!!
Last edited by Corvette40; Nov 12, 2011 at 10:34 PM.
Racer
Joined: Oct 2007
Posts: 478
Likes: 1
"you got 535 hp, and it goes thru the same exhaust...ya right. BTW those are called 'shorty' headers, they've been around since before you were born...probably"
The point of my post is how much horsepower the headers can support. It is also an indication of the quality of the headers. How many good 1 3/4" shorty headers are there available for the C4 Corvette? I know numerous people have been looking for a good shorty header. Now it appears there is going to be one available and it will come with or without the air tubes.
The point of my post is how much horsepower the headers can support. It is also an indication of the quality of the headers. How many good 1 3/4" shorty headers are there available for the C4 Corvette? I know numerous people have been looking for a good shorty header. Now it appears there is going to be one available and it will come with or without the air tubes.
Racer
Joined: Oct 2007
Posts: 478
Likes: 1
The shorty headers were on the motor when it was on the engine dyno. They were the exact same ones that were going into my car and I wanted to see what they would do. The car at about 3650+ pounds in weight has gone 11.57 @ 116mph in the quarter mile with a density altitude of 1800ft. Bottom line is the headers do work. You guys can call BS on my car if you want as I don't have a problem with it. I know what the car does and I also know how the internet works. 
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
I want to see these get produced people (in ca esp) will be lining up for them. Keep them stock looking with the air tubes, cover the afr ports.
Yep good product he will have there.
Yep good product he will have there.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Le Mans Master
Joined: Oct 2008
Posts: 9,758
Likes: 49
From: Houston Texas
Nice this is something we have been waiting for. 
Race Director
Joined: Apr 2003
Posts: 17,699
Likes: 1,667
From: moraga ca
I'm sure these are an improvement over the stock shorties, but I would like to see a comparison between these and long tubes. I would rather spend an afternoon and switch over to stock headers for a smog test every 2 years than leave major hp and torque on the shelf by not running long tubes for the other 729 days of the two years (if my car was on the street). For smog purposes, these headers will most likely not have an EO number (not worth it to pay the $$$ for a relatively small number of sales) so if you're fooling the smog police anyway, just swap out the tubes every other year. Just my 2 cents. Willie
Thread Starter
Racer
Joined: Jun 2006
Posts: 361
Likes: 6
As many times as I have been stopped here in SoCal, I wanted to keep the engine as stock looking as possible while retaining all the functional smog equipment, and pass smog. A doubt a novice would be able to tell the difference from stock.
Last edited by Corvette40; Nov 13, 2011 at 03:44 PM.
Drifting
Joined: Oct 2006
Posts: 1,328
Likes: 14
From: Stafford Connecticut
Headers
You do not know of what you speak Old Alaska man .Dyno Don knows what he's doing and yes there are many C4 owners who have been looking for exactly these headers every since I have been on this forum and before.I will be one of the first in line to buy a pair when they become available for sale.I have no doubt these headers will perform as good or better than some long tubes.
Last edited by steven mack; Nov 13, 2011 at 05:19 PM.
Advanced
Joined: Oct 2008
Posts: 66
Likes: 1
From: Fulshear, TX
Hey Dyno Don & 1989TransAm,
Since I plan on Dyno testing my 383 TPI engine when its complete next year, and I plan on using a set of Dyno Don's L-98 C4 headers on the car, I can do a header swap to any other headers that any of the Corvette Forum members would like to see results for. Just get the headers to us for my dyno appointment.
I will be happy to provide whatever data from my build that is required. My peak power should be around 6000 RPM ( give or take a couple hundred rpm).
Since I plan on Dyno testing my 383 TPI engine when its complete next year, and I plan on using a set of Dyno Don's L-98 C4 headers on the car, I can do a header swap to any other headers that any of the Corvette Forum members would like to see results for. Just get the headers to us for my dyno appointment.
I will be happy to provide whatever data from my build that is required. My peak power should be around 6000 RPM ( give or take a couple hundred rpm).
Melting Slicks
Joined: Nov 2005
Posts: 2,736
Likes: 0
From: WAY UPSTATE NY
You do not know of what you speak Old Alaska man .Dyno Don knows what he's doing and yes there are many C4 owners who have been looking for exactly these headers every since I have been on this forum and before.I will be one of the first in line to buy a pair when they become available for sale.I have no doubt these headers will perform as good or better than some long tubes.
