Cascade Crew

[jakemk8706]

whats the best approach on intalling my new shorty hooker headers onto my 91 350TPI

[aaron_sK]

Do you have A/C or an AIR pump system still installed? If so, you're in for a fun time. If not, it's easy.

What type/brand of headers did you get, and do they come with a Y pipe?

[jakemk8706]

ya i got the hooker ceramic coated shorties with the hooker y pipe, and yes i have air tubes(planning on taking them out) and AC

[aaron_sK]

Then it's going to be a bear on the passenger side.

First thing I would do is park the car and completely remove the AIR system, pump, and as much of the pipe as you can get out (to this day I still have about 18 inches of tubing behind my engine that I cannot remove )

Label and remove the plug wires, and pull the plugs so you don't snap anything off. IIRC correctly, post-87 L98's had the A/C on the passenger side, and the alt. on the drivers, so do the driver's side first.

If you're keeping your dual cat setup, this might get tricky. Personally, I would jack up the car and remove the entire stock Y-pipe, drop it down, and install the new Hooker piping. Then use some 14-gauge wire to suspend it via the crossmember or something.

Then, start on the drivers side (do the easy one first, so when you screw it up, it will be easier to fix ). Pull and save all the bolts, then pull the manifold. Drop the header in without the gasket, and fasten it with just a couple bolts to check fitament.

Assuming you're keeping stock A/C, I would remove all the bolts from the pass. manifold, and try and pull it up between the compressor and the condensor. No real trick, just try not to damage the tubing. Drop the new one in, and fit everything with a couple bolts and no gaskets, then install the gaskets on the heads first, torque everything down to spec, and then do the lower flange gaskets.

Were it goes after that is up to you. Unless you can smoothly clamp it into your catback, a trip to the muffler shop for a quick weld might be in order.

Sorry for rambling on, I'm a bit less than sober, and not really paying to much attention right now.

[QwkTrip]

I'll let you figure out the nuts and bolts of the job, but I would advise that you raise the front of the car so you have room to work from underneath. You will have to put one set in from the bottom.

[aaron_sK]

Hmm... is there really that little clearance around the A/C?

[alloy]

Yes there is very little clearence around the ac. Get some header bolts that are both hex head and allen. We have them at work.........I think about $10 for a set. They come with an allen socket. Also, do yourself 2 favors.

First get a set of good header gaskets. The copper ones, or the percy's aluminum ones. You do not want to do this job again. I "thought" I'd gotten good gaskets, but now my left side (thankfully) is leaking. I'm going with the percy's gaskets this time around. Wish I'd done that the first time.

The second favor to yourself is to run a tap in all the head bolt holes before installing the new headers. On the right side my car used the "7th" bolt hole for the exhaust manifold. The "6th" hole is there and tapped, just not used with the stock manifolds, but you will use it with headers. So it was getting rusty for about 15 years and it was a royal pain to get the header bolt in that "6th" hole without cleaning it out. I wish I'd ran a tap in all the holes. Hind sight is truly 20/20.

[QwkTrip]

Also be sure to tighten up the header bolts once a week for the first few weeks. The headers will expand and contract as they heat and cool and this will loosen the bolts.

Using aluminum antiseize makes it easier to move the bolts later and it is a necessity of you have aluminum heads.

[Twilightoptics]

[BigDaddyVu]

its easier just to pull it out the engine install the headers on the engine. I still retain my ac box.

[Quasi-Traction]

I don't know about installation, but I have a set of SLP's I removed off bobby's berlinetta, the driver side I had to remove from underneath, because I forgot to take the 02 sensor off first....

[QwkTrip]

[aaron_sK]

Seriously guys, installing from underneath the car, removing the engine? You're putting to much work into it.

Qwk is right about retightening the bolts though. I did it once a day for about a week, and it worked pretty well. Be sure to do it when the car is cold though. Otherwise it wont work, and you'll just get burnt.

[Xophertony]

when paul and i did my SLPs we had to unbolt one of the engine mounts and jack the driver side of the engine up about an inch or two. it was no big deal. however, while finishing up the next day i dropped the bolt between the Kmember and pan, then got my hand stuck attempting to remove it .

i also have no AC.

[aaron_sK]

Wierd. I have A/C and AIR delete with a heater-only box, and I have had both sides on and off a couple times with no big problems. Might depend on what brand you go with.

[BigDaddyVu]

its the size and shape of the headers

[Dewey316]

Paul and I did the hookers 2055's on my car, from the top, without pulling a motor mount. We took the alternator out, and we moved the A/C compressor around a couple of inches, but other than that, they slipped right in.

[QwkTrip]

I think those are the same units that you bought from me (welded off AIR tubes)? I helped install a set of those on my buddy's '89 IROC and we went from the bottom. I think it just depends on your imagination and how you prefer to tackle the job. I think what we are learning here is that there is more than one way to skin the cat.

[rjmcgee]

Now is the time for the good gaskets and locking header bolts. I used Percey's dead soft aluminum and Stage 8 locking bolts. Two years and I have never had to retighten them.

[Twilightoptics]

Napanitro seal gaskets all the way. I just used standard header bolts with some loc-tite. Tubes are too big to fit locking bolts for some reason.