Lemonsdemon

Hey guys,
I'm running a thirdgen Camaro that currently has the 305 TBI L03 in the 24 Hours of Lemons. Currently we have some Edelbrock 6872/7972 headers on there that look nice and clearly flow better than stock. However, due to the LO3 being a bit low on power, we're swapping in a LT1 out of a 95 Z28. Stock headers on that look pretty restrictive, so I'm wondering if our Edelbrocks will fit. I've read some things about headers designed for L03's not being large enough tubes for LT1's. But I've also read things about LT1 headers+LT1 not fitting the geometry of the 3rd gen engine bay. Plus since this is Lemons, we're on a very tight budget, can't just go buy shiny new headers. So if the Edelbrock's wont work, we'll be using stock, unless we can find some performance headers on a junkyard LT1.

Can anyone help with this?

FueledSoul

iTrader: (18)

You wont be able to run your current headers if you swap to a LT1 engine. Reason being is LT1 heads use D port exhaust ports You can not use the factory LT1 exhaust manifolds either. You'll need to find some D- port style headers made for thirdgens. I know Hedman makes a set of Long tube D-port style headers that fit thirdgens. http://www.summitracing.com/parts/HED-68469/
There maybe others to you'll have too look.

KiLLJ0Y

iTrader: (1)

not entirely true...

you can use headers without D ports so long as the primaries are 1" 5/8 or larger.. the 1 1/2" will be too small..

im using the headman 1 5/8" on my LT1 and they cover the D ports.

FueledSoul

iTrader: (18)

I have 1 5/8" primaries on my Hedman LT headers and they do not work with D Exhaust ports... Sure you can use them if you want the exhaust flow to ram into the header flange and have an increase risk of blowing header gaskets.

Lemonsdemon

Thanks for the responses guys. Looking at the exhaust ports, I can tell the shape is completely different. Turns out our junkyard LT1 is in really bad shape anyways

I'm taking the block in to see if it's still within honing tolerance, might just be getting a new engine from P&P, problem is LT1s are tough to find in there. Now we know why this z28 finally ended up in a junkyard though....

KiLLJ0Y

iTrader: (1)

i seriously, beg to differ.. plus i offer proof rather than your assumption..

the following 2 pictures are of my hedman 68481 1 5/8" primary headers on my 561 unported LT1 heads. the heads are off and on my bench, with the exhaust valve removed. Gasket is a Mr. Gasket 1 5/8" round.. headers are bolted completely to the head..

the picture is taken through the exhaust valve... what you are seeing is the Top portion of the header inside the exhaust runner, showing the meeting of the header to the head.

As you can see, there is NO over hang of the header, infact the top portion sits dead flush with the port. there is NO over hang anywhere of the header as to inhibit the flow. I cant get in there any closer with my camera, but i finger swept the port and there is NO over hang of the header.

So please show me where the flow is to "RAM" into the header flange please?

norcalz28

iTrader: (13)

My hooker 2055's have round ports and fit my d-port AFR heads just fine

KiLLJ0Y

iTrader: (1)

yep, a lot of people keep saying you need the D port headers.. and that round headers wont work.. well they wont if they are 1 1/2" primary rounds. the 1 5/8"s cover the ports just fine.

However, if you feel the need, they by all means go get the more expensive D port headers.

92rs85berlintta

iTrader: (1)

Not all 1 5/8th will work. I had a set of hedmans and the ports on the lt1 head were larger than the header port. It kept blowing gaskets. I switched to hookers 1 5/8th and its been fine. I compared the ports before putting hookers on and the hooker 1 5/8 fit exact with no lip. I think is hit or miss, but I do know at least the set of 1 5/8 heddmans i had, did not cover the port correctly.

the d shape on my stock head was exactly the same 1 5/8 wide as the header flange on my hookers. I marked the flange with paint and put them on.. When i took the headers back off could clearly see the headers covered the whole port.

So to the original poster.. just look for a set of hookers 2055 or 2460. Im positive they fit and are pretty cheap. otherwise heddman d ports the way to go, but keep in mind the y pipe is cheap and small at only 2.25 and even 2 in some spots.

Klortho

The round port headers make a step in the tube that isn't exactly wanted. It is best to use the d-port headers, some headers are also made for straight plug heads which put the tubes in different locations causing plugs to be hard to change and/or wires being burned. The Hedman's that I'm running are d-port, angle plug headers and they work like a charm.

FueledSoul

iTrader: (18)

I don't make assumption when i make statements, I have personally check this with 2 sets of hedman headers on 2 different LT1 head castings. Pictures don't mean anything since you can only see the roof in your pics, have you seen or felt your floor? There round tube primarys to D shaped exhaust ports... This isn't rocket science, use a dial caliper.