ajrothm

What are you guys using for headers since the exhaust ports are raised on vortec and Fast burn heads? Surely everyone is not just slapping on traditional SBC headers on exhaust ports that sit almost 1/4" higher.......I hate to have to buy new headers again but it seems most of the affordable crate motors or even the ZZ383 all have the raised exhaust ports.


Your thoughts?

andylmusic76

i am getting vortec heads for my car in less than a week, and i ordered standard sbc headers...i was told they will still work...
maybe there's some kind of gasket or adapter or something...

ajrothm

Yeah they will still bolt on but I believe the exhaust flange will block about a 1/4" of the exhaust port, at the top of the port where velocity is the highest(right where you need the most flow). I would look into it a little deeper before you install them. They may work but not flow worth a damn.

Little Mouse

Exhaust runner roof and floor would both be raised thats how they
make it a little straiter runner, the bolt pattern would be raised to
match the opening. The intake runner is the same way raised the
roof and floor to make the runner straiter.

ajrothm

So what do we do for headers to match the raised openings? or do we re-drill our current header holes lower and effectively just raise the header tubes up?

OK next question on the ZZ383 with the raised D port exhaust, will the Hooker Super comp 1 3/4" be large enough to work with these heads or do you have to have some kind of custom headers made using LT1 style tubes/flanges?

Durango_Boy

If the height difference is only .25" then you won't have room for a whole new hole. Filling the existing holes in with weld, and re-drilling is the only option outside of elongating the holes.

Little Mouse

You use the same headers the runner opening is just raised and the exhaust bolt pattern is also raised so the same headers fit. your
headers will just end up being raised 1/4 inch higher in the engine bay.
They don't just raise the port on raised runner heads they also raise the bolt
pattern up on the heads.

tigers123

gingerbreadman1977

i agree. i have GM fastburns on my 81. i had to bolt my stock block huggers on for 2 weeks until i could get to an exhaust shop. they worked fine but because of the extra height in the runner my huggers were contacting my steering box ( right hand drive conversion) . i got custom extractors made up as its my only choice over here. my vet over here has to be right hand drive so alot of parts will not fit straight of the shelf and exhausts headers is one of them regrettably. i also have a 71 split nose camaro and as its over 30 years old i can keep that left hand drive and i tell ya.. it is awesome just to look up the book and buy anything knowing it is original. here are some pics of the vet with the old exhaust..and..new exhaust

Brown78

In "05" I installed a ZZ4 385 w/Alum vortec fast-burn heads. I bought a set of
Hooker shorty's. Even with the "D" ports they work fine. I run side pipes without restriction. I don't know about running through a cat and muffler.

BKbroiler

I agree with everyone above. Vortec heads use the same header as earlier heads. The ports do not get restricted.

OzzyTom

I have the Edelbrock Etec-200 heads on my 383.
Although I could (just) bolt on the headers from my original motor, I found that the bolt heads were more difficult to get at as there was less clearance from the plugs.
I also had issues with the ignition leads failing (arcing to pipes) due to the heat from the pipes. The plug caps were touching the pipes on several cylinders. I tried using different leads with different plug caps, and even purchased some heat insulating boots.... but it was only a temporary fix.

I eventually decided to get new ones to solve all my concerns....
Custom 1.75" primary, tri-Y design with ceramic coating.

Now they fit properly, don't come loose and allow easy access to all plugs for removal/checking. And they look and sound good too.







Good ground clearance too.

gingerbreadman1977

how come you went with tri Y,s ozzy tom. i thought 4 to 1,s would be the go ? whats better?

ajrothm

Well that makes more sense.....I read on another message board that the exhaust ports were raised .200" but the bolt holes stayed in the same location. Basically the bolt holes are supposedly not centered with the centerline through the exhaust port now. I looked at a couple pics posted and it did seem that the ports are way taller on the top side of the bolt hole centerline then the bottom.

I just couldn't understand why they would make heads that require different headers for a SBC....although you don't see "vortec" or "fastburn" specific headers for sale anywhere.


So on the Fastburn heads with the D-ports, regular 1 3/4" super comp hookers will match up fine and not have a restriction in the port?

ajrothm

Here is what I read about the exhaust bolt hole/port thing:


quote:
--------------------------------------------------------------------------------
Originally posted by lastchevelle:
I currently run Hooker Super Comps, could i buy adapters and still use them?Was your trans built by a local shop or did you buy one? Thanks. Matt
BTW, why changing to BBC?
--------------------------------------------------------------------------------



Your headers will bolt up and work, as would any conventional SBC header. What happens, though, is the exhaust gas exiting the head will only "see" about 2/3 of the primary tube opening, the other 1/3 will be covered up by the header flange. If you look at your headers, the bolt holes line up along the centerline of the primary tubes. For an optimum header on the Fastburn head, the centerline of the bolt holes should be 0.200" lower than the centerline of the primary tubes. This would effectively raise the entire header on the head and make the exhaust ports line up with the primary tube openings.

I am not sure how much negative impact there would be by using a conventional SBC header with the Fastburn head. Probably the most economical solution for you would be to weld up the existing bolt holes on your headers and redrill them 0.200" lower. Someone on here did that but that was a couple years ago and I don't remeber who it was. I think Hedman makes headers with the correct flange for the Fastburn heads but I don't know if they make them for our chassis. They might work, though.

The adapter plates I was talking about would not work for your headers. Mine are Stahl, they have a plate that bolts to the head using the six regular bolt holes in the head and the header bolts up to the plate with seven bolts entirely a different pattern.

Stahl can build you the exact header you need but this is an expensive option. About $1200. IMO they are the best header I have ever used, in fact I just ordered a set from them for my BBC.

As far as a trans, I used a TCI. I would build my own but I don't have the time. If you have someone competent local I would consider that route. Or build your own, they are not that complicated.

It might be worth a shot to call Schoenfeld and see if they would you a set of headers with the correct flange.

If you think of any more questions, ask away.
Mike

Here is the entire thread:
http://www.maliburacing.com/forum/vi...ighlight=zz383

ajrothm

Here is a thread showing the modded headers for a vortec type port:


That was me with these Hedman Huslers on my Edelbrock E-Tec 200 (Vortec-style heads):


I filled the holes and redrilled them down .200", and I cleaned up the ports before having them ceramic coated.

If you don't do these mods, your headers block the highest-flowing part of the exhaust, and you lose power. Even more in a forced induction motor. Check them, and the gaskets, and fix any problems before you use them.

It pays off in the long run.

Jim

Little Mouse

I would imagine so if not what would be everyones options be go
to 1/78 primaries, on most small blocks 1 7/8 primaries would be
strickly a high rpm race header. although the 427 size small blocks
they make today 1 7/8 could be a good size for them.

Silver00V6Camaro

OzzyTom

4 into 1 pipes are good for racing.... provide excellent peak torque at rpm they are designed for..... longer primaries produce peak torque at lower rpm, whereas shorter primaries move peak torque to higher rpm.

Due to required length of primary pipes in a 4 into 1 system , the collector usually ends up under the floor pan, which compromises ground clearance. And generates a lot of undesired heat into cabin through floor.

Tri-Y's are a better design for the street..... designed properly, they provide a broader spread of torque across the rev range.
I'll get some idea if its been worth it after the motor is tuned on the dyno in a couple of weeks.

The pipes I had made also rout the exhaust alongside the trans tunnel, rather than under the floor pan as I had previously. I have added heat insulation to the firewall, trans tunnel and under floor pan, and it is now a lot more comfortable. Previously I would find it unbearably hot after 30 minutes of cruising in our summer... (we regularly have >100* F days in my neighbourhood)

gingerbreadman1977

ok thanks tom. that is a mad exhaust you have there with some wild bends. looks like it would have been a tuff one to do. yeah tell us how much power when you get the dyno