Well, I've got some extra money now and I've decided to spend it on some mods for my LT4 CE. The plan is put a set of long tubes (Hooker 2151s) on it and then get a farely streetable cam put in but, for now, I'm just concentrating on the header part.

I've done a little work on cars before so I think I can get the headers on myself but I have a few questions regarding the existing equipment bolted onto my stock manifolds. I've read that the LT4 came from the factory without and EGR system. Is this true? What are the metal tubes that go into the top center of my exhaust manifolds and then run into the back of my intake manifold (possibly air system)? If I install Hooker 2151s I suppose I will have to remove this system and, if so, will there be any problems if I just bolt a plate on the back of the intake manifold to cover the hole up? I know that I will have to have O2 bungs welded into the Hookers but is there anything else that will need to be done such as tuning, etc. (other than the obvious exhaust work to hook them up)?

Just to let you know, after the headers I plan on going catless with some O2 sims and then through a X-pipe and then on through my exisiting Borlas.

I know all of these problems could probably be avoided if I just paid the extra cash for the EM long tubes but I think the Hookers will be worth it even though they require a bit of extra work.

Thanks so much for the help guys,

Wes

 

There should be no problems with running the Hooker 2151s on your LT-4. You will need custom tuning to remove the AIR system from your OBD2 computer. As long as you have access to a good tuner this should be no problem. You will need O2 sims to run without cats because you are OBD2 also.

EM would be direct bolt on so that might be something to think about due to the custom tuning costs. I much prefer my LT-1 without the AIR tube mess in my way but that is my opinion.

You can look at the "my corvette pics" to see my Lt-1 Hooker header install.

 

victorrussel92's comments are good, but didn't explicitly explain that the metal tubes are air injection tubes fed by the electric air pump. a reprogram of the ecm can turn the system off and eliminate the obd-ii light. however, keep in mind that it shows up in a scan as test not being complete. in texas, 3 incomplete tests are enough to fail. for my LT4 (396), i have to disable the cat monitor, misfire, and AIR. so, it can't pass.

used to be you could force a tailpipe test under certain conditions, but no longer. now it must pass the obd-ii hookup.

-michael

 

Thanks for the reply. Looks like I may just break down and purchase the Exotic Muscle long tubes (they are about $750 right?). I figure after paying the initial cost of the Hookers, paying to have them coated and O2 bungs welded in, and then dealing with removing the AIR system, the EMs may just be a better deal for me. I also get the impression that the EMs may be a little better quality and fit.

Thanks guys,

Wes

 

Another very good option for the LT4 are TPIS long tube ceramic coated headers. They fit well and have plenty of ground clearance. Have been running mine for over 2 years with no problem. Still look good, too!

 

Sorry to bump an old thread lol, but are you saying that the TPiS longtubes will fit an LTx motor?

 

Yes

http://forums.corvetteforum.com/c4-t...t-headers.html