2000+ 3x00s EGR Adapter Plate and Headers

[TheDirtyBen]

ok, so the original 3100 engine in my 94 achieva died back in september @ about 176k miles. i was recently able to pick up a 2002 3100 for $225. i had already knew about the different EGRs. well, it turns out i have a good friend here in town that is a machinist that owns his own company. favor for favor and he is making me an EGR adapter plate.

with that said, him and i got to talking. is there a market for these adapter plates out there? he also brought up the idea of equal length headers. i brought up the problems and difficulties that others were having in this forum. he's certain that he can make them. maybe even make heat shields for them. he's more interested in making do-it-yourself header kits and you just weld all the pieces together, but i may be able to have another shop put them into bolt-on form.

so, i need everyone's input here and try to come up with a consensus of what people want.
#1) how many people are interested in a EGR adapter plate that would fit 2000+ 3100s and 3400s? this would mount your 3-solenoid digital EGR to the new engine.
#2) how many people are interested in dual length headers, and what style? do-it-yourself kit or bolt-on, collector terminates into single exhaust, or duals?
#3) i need optimum header tube and collector diameters for these engines.
#4) i need to know how many different rear manifold styles( downpipe) there are in case we do something where the headers bolt up to your stock exhaust.


thank in advance for everyone's input

[TheProfessor]

i would be interested in both the headers and and adapter plate for the 2000+ 3100

[Anonymous]

Just an FYI, take all the people interested and divide by 4, and that is how many will come through when you have it done. it sucks. but that's life.

As for the headers, for a stock to nearly stock 3100, I'd be using 1.5" diameter and in the neighborhood of 35-40in length. This will maximize midrange, helping high end, without too much of a hit to the lower side.

But if I was to make headers, I would not include the EGR. It is needed for emissions in some states, but you arne't going to pass with headers anyway.

[SappySE107]

Why can't you pass emissions with headers? Who puts headers on a bone stock 3100 with no intention of more mods? Lets be realistic. Header kits...just go the extra step and weld them. Try fitting the headers in there and see what length you can honestly do without too much custom fab of the engine bay since most people want cheap headers with arms and legs that install themselves.

EGR adapters, there are a few people already making these, I just need to know who and how much so I can try to get them added to the 60V6 store for its opening.

[TheDirtyBen]

i realize that not everyone interested has a wallet that is interested. we think that we can make (and still turn a profit) the EGRs plates for under $100. the headers will be dependant on what most people are interested in. obviously a do-it-yourself kit will cost a lot less than a bolt-on and go set up.

[TheDirtyBen]

if you have other ideas of stuff that needs fabricated and isn't being done, let me know. and would somebody please get into re-programming 94-96 PCMs? My achieva is dying for fresh code, not to mention eliminating the rev/speed limiters!!

[SappySE107]

You wont sell any for 100...someone else was selling them for 50 I believe. For a header kit, those are already available so if you aren't doing any real work on making a complete set that fits, its pointless to sell tubing to people. You could probably sell header flanges with stubs on them for the start of pipes.

[Anonymous]

Why can't you pass emissions with headers? Who puts headers on a bone stock 3100 with no intention of more mods?.

Going off of Colorado standards. I passed before them, failed miserably after them. But I also eliminated the AIR pipes and the EGR. So that could explain the fail. In some other states, won't a emissions tester automatically fail you if he sees aftermarket headers? Or as long as it passes, it passes? I don't really know.

[Guest]

Why can't you pass emissions with headers? Who puts headers on a bone stock 3100 with no intention of more mods?.

Going off of Colorado standards. I passed before them, failed miserably after them. But I also eliminated the AIR pipes and the EGR. So that could explain the fail. In some other states, won't a emissions tester automatically fail you if he sees aftermarket headers? Or as long as it passes, it passes? I don't really know.

Aaron, I would have thought that you would have learned by now to stop spewing out the misinformation that you have collected.
Yes, your fail came from non functioning emissions equipment, not the headers.

I have home made shorty headers on my Franken60, and it passed with flying colours, also had way to large of an injector, un-tuned PROM, among many other things that weren't exactly "right", but the headers did not make it fail.

I have known many other people in other vehicles with headers, that have passed.

As for the visual side of things, that depends on the state/province, and more specifically the actual inspector.

[Anonymous]

Yes, your fail came from non functioning emissions equipment, not the headers.

It can't be proven. That's my guess too, that's why I said it. But who knows.

I have home made shorty headers on my Franken60, and it passed with flying colours, also had way to large of an injector, un-tuned PROM, among many other things that weren't exactly "right", but the headers did not make it fail.

I have known many other people in other vehicles with headers, that have passed.

And I have known many that headers made them fail. I don't see this makign a difference, but maybe it can be slightly attributed towards me having longer tube, equal length primaries. Again I doubt it, but who knows...

[TheDirtyBen]

complete sets can be done, but i know that there are different downpipe configurations. so there couldn't be a one set fits all, unless you were to modify the rest of your exhaust. also, i don't know if people want them to terminate into duals or into a single exhaust. i guess i could assume a single exhaust because of the O2 sensor

[Guest]

complete sets can be done, but i know that there are different downpipe configurations. so there couldn't be a one set fits all, unless you were to modify the rest of your exhaust. also, i don't know if people want them to terminate into duals or into a single exhaust. i guess i could assume a single exhaust because of the O2 sensor

My suggestion would be make the header the way IT needs to be, there is almost no way you will fit equal length (long tube) headers to use the OEM down pipe, too short. look at any long tube headers out there for other applications, all require a new downpipe.
I know I'd rather put a little more effort into modifying the exhaust and get some real gains than to sacrifice the potential to save a few bucks or minutes. ;0

I'd also say into a single exhaust.

Aaron STFU.

[SappySE107]

Yeah, definetly say to hell with anything stock for exhaust. Also, if some moving around or modifying is needed to fit the headers (without cutting the subframe...or anything else that will hurt structural integrity), go for it. Just make a set for a certain platform, then go from there. Quality and performance are the 2 key issues.

[geoffinbc]

For the adapter plate there is a little more work involved thn just making a plate. You have to do a little clearancing on the stock adaptor that has the hose coming off of it. Also you need to make a special fitting to make the old EGR hose screw into the new 3400 manifold. And onn that fitting you need to buy a 90* AN fitting. Then you need to do some thread taping in the new adaptor you make and find/buy the right length bolts.

Lloyd and I are the only ones I know of who have made a 2000+ Adaptor. I would relally like to see some other plates to compare design't.

The way we did ours we used all the old 3.1L Stuff and made it work with the 3400. I supose if you had some of the new and some of the old stuff you could make a "hybrid" EGR system. But the engine we got was missing all the EGR stuff.

[blackbombshell95]

I WILL BUY AN EGR ADAPTER RIGHT NOW VIA PAYPAL!!! I'M READY, LOOK AT ME, ME ME. PICK ME. I 'M READY TO BUY ONE !!!

shit. i've already tried in vain to buy one. and no one will frickin make me one.