I agree, gives us something to do when we are not in the woods or desert away from the crowds!
Group Buy - 100 Series Headers
- Thread starter uzj100
- Start date
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I am going to change out the manifolds next weekend and had a question. After the headers were installed, and before you put the LC back together, did you crank the car, let it heat up and then re-tighten the nuts?
I had a friend that has been installing headers on Chevy/Ford cars forever and he said this is very good to do. He said the heating and cooling will change how much they need to be tightened. I just hadn't heard or seen anyone mention this during the install process.
Has anyone checked to see if the nuts are loose after installing if they didn't start and stop the engine before putting it all back together?
I had a friend that has been installing headers on Chevy/Ford cars forever and he said this is very good to do. He said the heating and cooling will change how much they need to be tightened. I just hadn't heard or seen anyone mention this during the install process.
Has anyone checked to see if the nuts are loose after installing if they didn't start and stop the engine before putting it all back together?
r2m
Richard
It's not that the nuts are loose, it's that they loose there torque.
The thermal expansion will expand the nuts, threads, flanges, etc. and when it all cools, verything will not be as tight. But I don't thing anything should be "loose".
Yes, I did do exactly that, however none were found loose. I also used anti-seize on the threads.
So you would recommend starting the truck and letting the headers heat up and then cool back down and checking the torque again? It does make sense to me. Just want to make sure it's done correctly the first time as I don't want to have to go back in to re-tighten anything 3 months down the road.
I went back and checked a couple of days later and no change. It's not a big deal to get access to them so I wouldn't sweat it.
Thanks. Will do the same thing with my install. Looking forward to a quiet(er) ride!
Do these headers fit the '05? Anybody with an '05 buy and install these headers?
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Wasn't someone going to post Dyno results before and after installing these as well?
Lots of people have talked about it or tried but full time 4 wheel drive really needs a rather rare 4 wheel dyno. Most guys have just defaulted to the results from the Tundra dyno tests. The guys at DT said that it will be nearly identical to those results. Which were impressive.
Haha, just posted them and then read this. How ironic...
DesertRun,
you posted early on in this thread about how high-flow cats were a waste of time. That would depend on your cats.
Ours in Oz actually reduce in diameter before and after the cat....and then the factory exhaust goes back to 2" either side. (or whatever the diameter is)
It IS a serious performance issue on our factory V8's here. I'm not sure what diameter your exhaust is when it goes into and exits your cats, but here, the diameter reduction is easy to see and easy to see why you get a performance increase if you replace the cats or cut off the restriction and weld on wider pipes, which i know has been done here.
I have high-flow cats, and kept my factory cats in my spare parts bin (coz i know what they're worth) and as i said above, the reduction of the diameter of the pipe is easily seen.
So dont necessarily dismiss high-flow cats, because it depends on your year and most likely your location too.
cheers
peter
you posted early on in this thread about how high-flow cats were a waste of time. That would depend on your cats.
Ours in Oz actually reduce in diameter before and after the cat....and then the factory exhaust goes back to 2" either side. (or whatever the diameter is)
It IS a serious performance issue on our factory V8's here. I'm not sure what diameter your exhaust is when it goes into and exits your cats, but here, the diameter reduction is easy to see and easy to see why you get a performance increase if you replace the cats or cut off the restriction and weld on wider pipes, which i know has been done here.
I have high-flow cats, and kept my factory cats in my spare parts bin (coz i know what they're worth) and as i said above, the reduction of the diameter of the pipe is easily seen.
So dont necessarily dismiss high-flow cats, because it depends on your year and most likely your location too.
cheers
peter
Not sure if or when I made that statement, but I would definitely say for the cost it would be VERY expensive for the benefit, unless you needed to replace them due to damage. I wanted to replace the on my truck headers ONLY because they were cracked and making noise. The performance increase is just icing on the cake.
page 11 at the top
https://forum.ih8mud.com/100-series-cruisers/347955-group-buy-100-series-headers-11.html#post5347365
EDIT: here's the link to my cat pics
http://www.loved.com/images/cats/
The first 3 pics are the same due to automatic SLR camera, but checkout the others and see how restrictive the Oz factory cats are. To say they aren't is blown away by the pics. The cats ARE restictive. Maybe your USA ones are different.
checkout where the clamps are and see how it reduces in diameter. Thats where they cut it off and reweld a bigger diameter pipe if the customer wants to keep the factory cats. Duplicate pics are there coz of the SLR camera.
cheers
peter
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Another quick question....How did you raise the engine when doing the install? Is there a place that it can be jacked up from below or did you use some sort of cherry picker or engine hoist?
Not sure about the diff in cats here and in OZ, but the guy here in my local muffler shop would not even sell them to me since he said they would make no material difference over stock, AND cost big $$$$.
I used a block of wood with a floor jack. I jacked at the rear of the engine near the oil pan flange. You don't have to move it very far.
Thanks. Going to attempt it tomorrow and through the weekend. Have my fingers crossed!!
my pm's go right to email, so feel free to ask questions if you need help... or post here, there's a couple of us who have done the headers ourselves.
realistically, the determinant of whether your day will go well or not will be getting the original nuts off the studs. I was lucky and got them all loose with hand tools and had zero studs break or back out. If you're corrosion-free you can probably expect a good day. If not, use PB blaster ahead of time to improve your odds.
These pics show the block/jack. Not the best angles, but you get the idea.
The 2nd one shows where I removed the dipstick and plugged the hole with a shop towel.
