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I've been complaining about what I originally thought was my transmission leaking fluid on the the midpipes putting some smoke into the interior. After removing the tail case and reapplying the proper sealant (black) the issue wasn't as bad but still happening. The other morning I started the car with the hood up and noticed exhaust coming out between the flange and the tubing, not between flange and heads, but externally at the flange. Sure enough I could see 4 locations where over time the exhaust manifolds have been leaking into the engine compartment. Last thing I wanted to do is remove the headers and have them welded up so I picked up some JB weld ultra high temp epoxy. I put a small bead around the areas where the leaks were occuring and as far as I cant tell the exhaust leaks are gone.

Best part is the epoxy cures almost the same color as my flat grey ceramic coated headers.

I've had these Kooks LT's for a long time and didn't notice these leaks until a couple years ago. I doubt they are coming apart.
:gto_rage:
 

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I made the mistake of sneaking under my '06 Goat during the replacement of the right-front hub assembly (w/Timken) and an alignment. I noticed that the right-side exhaust pipe (between the dual-front and right-rear mufflers), has a blatant inward BEND to it near the U-joint's center carrier bearing flange.
I am thinking that BEND (2" flattened portion) was not designed into the pipe, which effectively restricts the inner diameter by at least 20%. I may have bottomed the car out and caused it.
The mechanic thinks that it was designed that way intentionally.
I am also thinking that w/o dropping down the exhaust, it can be brought back to being round again w/some sort of a clamping/pressure force but ONLY if it was a clearance issue to begin with and had to be intentionally designed in. Some of the service manual parts breakdown drawings kinda show some weird circular lines around that area of that right-side exhaust.
Anyone know the answer?
 

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Powdercoat all of it
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181 Posts
I made the mistake of sneaking under my '06 Goat during the replacement of the right-front hub assembly (w/Timken) and an alignment. I noticed that the right-side exhaust pipe (between the dual-front and right-rear mufflers), has a blatant inward BEND to it near the U-joint's center carrier bearing flange.
I am thinking that BEND (2" flattened portion) was not designed into the pipe, which effectively restricts the inner diameter by at least 20%. I may have bottomed the car out and caused it.
The mechanic thinks that it was designed that way intentionally.
I am also thinking that w/o dropping down the exhaust, it can be brought back to being round again w/some sort of a clamping/pressure force but ONLY if it was a clearance issue to begin with and had to be intentionally designed in. Some of the service manual parts breakdown drawings kinda show some weird circular lines around that area of that right-side exhaust.
Anyone know the answer?
Mine had the same, pretty sure that's factory.
 

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2005 Pontiac GTO
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570 Posts
Started the head/intake swap this evening. After taking this picture, I had to remove the headers (easy, just 4 bolts since they were already unbolted from the heads), and unbolted the rocker arms and slid the pushrods out. When I watched the #1 cylinder rockers to approximate TDC, I noticed there are 2 pairs of small holes on the balancer that were centered on the bottom at #1 TDC. When I pull the heads, I'll see how close I am to actual TDC.
 

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I was a 1/4 turn from TDC. The pair of 2 dots are facing to the left (pass. side). Heads and lifters are pulled, decks cleaned, and threads are all cleaned out and chased (used Q-tips to clean the coolant out of the holes). Lifters all looked great, but with 142k miles, no sense in not replacing them and the trays.
 

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2005 Pontiac GTO
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Done, fired it up around 10 pm. Woot! Sounds as smooth as before, so it looks like I didn't screw anything up. Noticed a little drip from the radiator, it's been doing that off and on for a while. Yep, original radiator with over 142k miles. :eek:

Anyone want some used 243 heads and an LS2 intake? $400 for it all, and I'll throw in the OE head bolts, pushrods, rockers arms, and lifters. :)
 

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2005 Pontiac GTO
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Made a 2nd gear run yesterday and compared the injector duty cycle (up to 84% on the LS2 injectors) and pulse width to my dyno run. From 3600 rpm to 5000 rpm, they both gained between 5-9%. From 5200 to 6300 rpm, gains were in the 9-11% range. Airflow also gained about the same, but the readings are much more erratic compared to the injector readings. I noticed that the spark values are being pulled from another row or 2 higher in the spark advance table, so I had to adjust the values in those rows and smooth things out. I'll do some more street tuning before scheduling another dyno pull.
 

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Done, fired it up around 10 pm. Woot! Sounds as smooth as before, so it looks like I didn't screw anything up. Noticed a little drip from the radiator, it's been doing that off and on for a while. Yep, original radiator with over 142k miles. :eek:

Anyone want some used 243 heads and an LS2 intake? $400 for it all, and I'll throw in the OE head bolts, pushrods, rockers arms, and lifters. :)
now you ask, after i already have 3 pairs of heads and two truck manifolds.
 

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Currently in process of jba shorty, jba catted mids, SLP cat-back. Daily Midwest driver with over 124k and those stock bolts were not possible to remove. Took me a whole day to get them cut through pre cat since that angle sucked so bad and I didn't want to slice the O2 sensor so I could drop the midpipe and back and pull the stock manifold up. Just finished getting the headers/mids and the xpipe in but gotta finish up the rest after work today. Kinda wish I would have known the SLP was going to arrive Tuesday because then I could have worked on it over memorial weekend.

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Finally removed the old and installed the new LS2. Same size but with forged bottom end, and H/C/I. Replaced the sway bar while the engine was out too. Having trouble with startup though. Tuning is an issue. One company says just increase startup airflow 20%, then 30, then 40 to a max of 50. If no luck, add 5-10% startup fuel. And there is also a startup spark table you can play with, but no real instruction. Seems there is so much more at work than just those 3 options. Tuning is an art form and much more complicated than initially thought. It's difficult to get straight answers and information from most tuners. They keep it close to the chest. The books and dvds for sale appear to be bait. I think they do give you some information but only scratch the surface, and leave you scratching your head.
 
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