87 vette 81 big girl

Are there any available headers for a C4 with 23 degree or 18 degree SBC

cylinder heads that have 2" inch primary tubes X 27-28 inches in length

and have 3-1/2" to 4 Inch exaughst collectors ?

Many say that 1-3/4" to 1-7/8" primary tubes are big enough.

But I prefer very large primary header tubes.

Loss of bottem end torque is not a concern.

Engine will have around 550 ft/lbs of torque.

High RPM breathing up to 8,000RPM + is why I like large tube headers with large collectors.

BR

5POINT7

I would think your best bet would be to have a custom header shop make them for you. I dont know of any 2 inch primary headers. hopefully others will chime in as well.

engle1147

or buy pre-bent big block tubes or a DIY kit and weld up your own.

tpi 421 vette

I have a set of 2" primary and 3.5" collector headers on my car. I bought them on the forum. They are hand built, and fit better than most smaller headers. And sparkplugs are easy to get at. You will definately to have them hand built to get that size.

yedister

18* degree heads will be custom, I have 15* degree custom 1-7/8" primary with 3-1/2" collector and there are a tight fit. What are you building that will go to 8000 RPM? and why would you need to spin it that high? I am sure that you can make the same power under 8000 RPM. Judging by the headers size that are in question, this is not a small size motor.

Steve

1989TransAm

We don't know what you are building but in your case maybe "stepped" headers may be the way to go.

87 vette 81 big girl

No its not a small motor.

The engine is already built sitting on one of my engine stands.

Same engine is used in Winged Warrior Dirt Track Cars and they put out about 900 HP + running on Methonal alcohol fuel with a Kinsler, Hilborn, or Crower injection with a Vertex Magneto.

Some are direct cylinder head fuel injected also.

A friend has a similar spec SBC engine but all iron- cast iron heads, in a 1985 Mustang, 2800lb race weight, 150 HP shot of Nitrous, runs 8.30's in the 1/4 mile. 60 foot times of 1.3 - 1.2 seconds.

He uses Custom LEMON Headers- cost $2k.

Dave put an early C4 Corvette emblem on the front of his 5.0 bodied Mustang to drive the other die hard Ford guys nuts. LOL

I had thoughts that custom headers would have to be fabbed up to fit a C4 with 2" primary tubes and 3.5"-4" collectors.

Nice to see that there are a few sets of Very large tube SBC headers have been built.

Does anyone have any pics of how 2" inch primary tubes fit on their SBC C4 Vette ?

tpi 421 vette

Here are a couple pic's of my headers. A 2" primary also requires a adapter plate between the head and header that changes the bolt pattern. Otherwise the tube would cover the header bolt holes in the head.

87 vette 81 big girl

Thanks for Your pics of your C4 Big tube 2" inch headers.

I also thought that header adapter plates would be required.

Whats it like fabricating your own headers?

Is it a real PIA ? Never have tried making a set of headers from scratch.

I am handy at fabricating, machining, and MIG welding.

Never tried to TIG weld yet.

But I can also Acetylene gas weld and use an AC-DC Lincoln stick welder.

I was checking out Stainless Headers.com, Kooks, and Lemon headers earlier tonight.

Big tube SBC headers in primary tube diameters from 2", 2-1/8", & 2-1/4" are fairly common outside of the C4 Corvette group.

Used by drag racers often today.

Are C4 headers unique from any other header style used in other GM platforms?

Such as Camaro, Firebird, C3 Corvette, A-body Chevelle, GM G body ?

Is it a total waste of time looking at other Big Tube SBC headers from other non C4 cars?

In the past, i had some luck using headers from a F-body GM and into a A- body GM and Visa Versa with light mods to the primary tubes and collectors.

Chicago Drag Racing Expo is coming up here in Illinois at the end of this Month. Feb 26 & 27th.

I will be there checking out all of the latest drag racing goodies from all top vendors and hitting up the HUGE drag race gear swapmeet as usual.

Wintertime fun for us hotrodders and racers here in the midwest winter.

Maybe get lucky and find the headers I want and need for my Stroker SBC engine.

BR

tpi 421 vette

I bought these headers used from a forum member. I did build a set of headers back in the 80's for a old race car, and it probably took 3 days. Was pretty tedious, and time consuming. If you have good welding skills, you could get a weld up kit from one of a bunch of different sellers and give it a shot. I could try to send more pic's of different angles if it would help. I thought these turned out nice. They fit well, and everything is easy to get at. I don't know if F body headers or anything different will fit out C4's. The way these wrap around the steering, I think you need C4 specific headers.

davenbocafl

if its a street car,its about the worse thing you can do, unless your turning 10,000 rpms, you loose all your torgue and hp under 6,000. I use to run 2 1/8 on a 283 in F/G but we never dropped below 9500 and left the line at 11. anyway ,you can ask for dale at Hooker and he will make you a set custom to what you want.

87 vette 81 big girl

You may be right.

I may loose torque on the street with large tube 2 inch primary headers.

I have a built 410ci sbc on my engine stand.

It has all real American made parts inside. Premium parts like Crower, Isky, Brodex and Manley.

Was built by a late buddie of mine. Left the engine for me to have and to do with as I want or please.

His said install into my 87 Vert with a large smile before the cancer took him for good.

Its been a dream of mine to install it. 2011 looks like a good year to do so.

I always liked large tube headers.

When I built and raced my Pontiac cars, I was told large tube headers would kill the bottom end torque too and the car would be slow at all speeds.

I found the opposite to be true. Picked up torque, HP, and usable rpm power band.

From off idle to 8,000 + RPM's my 70-1/2 Pontiac Trans Am ran great.

Very hard time hooking up without feathering the gas carefully on the street. tap the gas and the rear tires goe up in smoke and car is sideways and engine roaring away.

From 400ci to 462ci Pontiac Big blocks. Used 2" inch Primaries with a 3-1/2" collector with true mandrel bent daul 3" exaughst to the rear bumper and 2 chamber Flow Master Mufflers.

Pontiac engines are all of "STROKER" design. Have a a tall deck height of 10.230", Long connecting rods of 6.625(6-5/8"), and crankshaft strokes ranging from 3.75, 4.00", and 4.21" stock.

You can also fit a 5" stroke crankshaft into Pontiacs.

My experience is that 400 + ci engines of any make like to breathe deeply on the exaughst side if the rest of engine is built to match.

My 410 CI SBC is built to make use of a large tube header if I choose so.

tpi 421 vette

If you have enough cubes and some rpm, you can benefit from a bigger header. My car picked up .2 and 2 mph going to a 2" primary 3.5" collector over a 1 3/4" 3" collector header. My engine never see's more than 6000 rpm. And it makes over 400 rwtq N/A from 1800 rpm to 5500 rpm. So it still has alot of low end power.

But 2" primary tube headers aren't for everybody.

KO1

www.stahlheaders.com make 2" SBC C4 Headers

87 vette 81 big girl

Thanks!!!!!!!!!!

If you have any tough questions on engines, A4 transmissions, rear differentials, and Vertex magnetos ignition systems I will do my best to help you.

PM me.
My help is always free.

If you want to hire me to repair something let me know too.
I charge by the job, not by the hour.

No one from C4 has ever hired me after 3 years anyhow.

So I give tips and help out free.

But Vertex magnetos I keep all repair and blueprint modifications I perform to myself.
My own nitch in life.

Brian

mgroshong

You can certainly put a 2" primary tube on a standard sbc flange. It is not very fun for the fabricator but it is doable. I just did this on a set of headers last week that i made. (i make headers for a living) Now this did take forming the tube to a rectangle and doing some die grinding to smooth flow, but all in all it didn't take much longer then a standard 1 5/8-17/8" header.

I can also tell you that you better have one serious set up to need 2" primaries. It can also be misleading to see gains from going to a larger primary tube if you had a poor set of headers ( ie: crap design, non-merge collector) with a smaller primary size. The design will help alot more then tube sizing.

OP the only way i would try to fit a set of 2" headers in a c4 is if they were custom made (denting tubes sucks).

87 vette 81 big girl

I have a serious 410 SBC engine that just needs an induction system of my choice and I want 2" inch Primary Tubes roughly 27-28" inches long with a 4 inch collector.

I do not want to have to dent the header tubes.
I hate that.

I already have an idea of your price $$$.
Money talks in the performance HP game I know.

You have a contact # or email?

PM me if you want to build a set of headers for me to fit my 87 vert.

I will pay if you can deliver what I want.

Do not tell me that you need $5,000 US dollars.

I will head to a couple of Pro Stock car builders I know of in Chicago instead then.

Brian R.

mgroshong

I do not sell headers unfortunately. I work for a company that produces them. You can pm me for there contact information. I prefer to not break my non compete, so idk where that stands posting publicly online.

Steve85

1 -7/8" w/ 3.5" collector for 18° heads in a C4. Also have the heads and EFI converted Wilson/Edelbrock intake I won't be using.

marvinator

Try t.p.i.s. They are on the internet out of ohio i think. Got a set from them 4 my 85 ruinning 383 stroker . They fill up the engine bay . Had to run ngk shorty plugs but car pulls hard and hauls .