$275 for HFC install?
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$275 for HFC install?
What do you guys think, is $275 a bit much for installation of high flow cats? I've heard tales of the "demon bolt" and I really don't want to get into a situation where I spend two hours drilling out a bolt on a 100 degree day while under a car on jacks.
With that said, I personally feel $275 is a bit rich. I've got a 3 foot breaker bar, plenty of PB Blasters and an impact gun. Maybe add a propane torch to the mix? Blast the bolts the night before and tackle in the morning?
With that said, I personally feel $275 is a bit rich. I've got a 3 foot breaker bar, plenty of PB Blasters and an impact gun. Maybe add a propane torch to the mix? Blast the bolts the night before and tackle in the morning?
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LOL. Yeah I'm reading a few threads now about it. Thinking that may be a good game plan. The shop has done them on the G/370 more than a few times so...they probably charge from experience.

FWIW, if you do give it the DIY try, be sure to use the Black Betty rust breaking cocktail, it's about 10x better than PB Blast, just a 1:1 mix of Acetone & ATF.
Here's my thread w/ the tools I used in the first page (the Harbor Freight wobble joints were key).
https://www.myg37.com/forums/g37-sed...y-be-atch.html
It wasn't the easiest DIY for sure, but one that you can be proud of when you're done, lol.
I can't personally take credit for the Ultimate Homemade Penetrating Lube, I wish I were smart enough to have come up with that. But it makes a world of difference.
It can be DIY'd. But even for someone fairly skilled there's a lot that could go wrong that would leave your car out of commission. Namely snapping those bolts or studs and having to drill or torch them out. That'll ruin your weekend. That's why I usually recommend letting the shop deal with it unless you are extremely skilled and experienced with this sort of thing. You need to have a decent impact gun and the long impact extensions. If you have to buy those things for this job you're going to spend almost as much as paying a shop to do it. Plus you'll have to deal with the fallout yourself if something goes wrong. Or end up towing it to the shop in end and paying them to fix/finish the job.
If you know you have the tools and skills, by all means go for it. But my assumption is that if you posted the thread to get input then you aren't 100% sure you can pull it off yourself.
It can be DIY'd. But even for someone fairly skilled there's a lot that could go wrong that would leave your car out of commission. Namely snapping those bolts or studs and having to drill or torch them out. That'll ruin your weekend. That's why I usually recommend letting the shop deal with it unless you are extremely skilled and experienced with this sort of thing. You need to have a decent impact gun and the long impact extensions. If you have to buy those things for this job you're going to spend almost as much as paying a shop to do it. Plus you'll have to deal with the fallout yourself if something goes wrong. Or end up towing it to the shop in end and paying them to fix/finish the job.
If you know you have the tools and skills, by all means go for it. But my assumption is that if you posted the thread to get input then you aren't 100% sure you can pull it off yourself.
Last edited by Black Betty; Jul 8, 2016 at 09:13 AM. Reason: typos
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Do the DIY route...much more satisfying and you get a workout in the process.
Took a couple hours to get those top bolts off...had to have a buddy help me from the top side but overall worth it.
Took a couple hours to get those top bolts off...had to have a buddy help me from the top side but overall worth it.
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I actually looked to see what I could get for $275 worth of Snap On tools and have to say it's tempting to go that route. Thanks for the links and the tips, much appreciated. It honestly was more about the cost than the skill. I got a verbal $200 and when I asked again via email (to get it in writing) it shot up to $275. And if everything goes well (hey, it can happen), seems a bit much. I'd feel like an idiot if they came out an hour later with the car complete.
As far as being able to do it myself, I have the skills but not necessarily the heart to spend a day doing what should be a two hour job tops (with correctly implemented designs and bolts). Plus it's 100 degrees daily here for the foreseeable future. But...if something does go wrong, no acetylene torch although I do have a high speed die grinder I used for porting. I do believe I have an extractor set somewhere and I have the rest of the tools although I'd want a super high quality 14mm six sided swivel impact socket and maybe a higher quality extension.
As far as being able to do it myself, I have the skills but not necessarily the heart to spend a day doing what should be a two hour job tops (with correctly implemented designs and bolts). Plus it's 100 degrees daily here for the foreseeable future. But...if something does go wrong, no acetylene torch although I do have a high speed die grinder I used for porting. I do believe I have an extractor set somewhere and I have the rest of the tools although I'd want a super high quality 14mm six sided swivel impact socket and maybe a higher quality extension.
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the only real thing that snags people up on the cat install are rusted bolts. if you think you have really rusty bolts I d take it to the shop because they might need to be cut. Also they can ensure you don't have a leak anywhere
I got mine installed last year for $100 at a local shop. Mine was a used car from New Jersey when I bought it so I know the bolts were bad on there. I had put on Top Speed Axleback a couple of months ago and need the nuts torched off cause hey we're so rusted. Didn't see the HFC install but I know it had to be as bad but prob didn't need torching off though. $275 is pretty expensive though. Looks like they are charging for a 3 hour job when it's an hour one...
Tight quarters and stuck nuts are the PITA for this job. Mix up a batch of the Ultimate Penetrating Lubricant and apply it liberally. Drive the car during a normal day to heat cycle it. Apply again and let soak overnight. Take it to a shop and just have them break the tough bolts loose. Maybe 1/2 hour, $30-40? Then take it home and finish the job yourself worth the hardest part already done.
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Looked at the bolts today while changing the oil, they don't look friendly to say the least. I like Black Betty's idea and I may give that a whirl. One thing I noticed, the bottom bolt is screwed in from the front to the back of the car. It was my understanding it was one top bolt that was like that with the other two bolt heads facing the back. Or did I have it in reverse?
I took a photo or two, will post when I have a chance.
I took a photo or two, will post when I have a chance.



does sound like a bit much...