Hello Everyone,

I am changing my exhaust and I just managed to get the driver's side manifold off. I wanted to check and test fit the exhaust manifold gasket before I try to squeeze the headers in and found the gasket doesn't seem to fit. No matter how I start to seat it, I can't get an end hole to go over the stud. Are you supposed to remove the exhaust studs to install the gasket? It is a OEM Nissan gasket.


Thanks,

Arman

 

Ok.

It's important to admit your not perfect. As it turns out, I had the OEM manifolds on the ground. When lined up the new gasket to the original one, I compared it to the original against the upside down manifold. So I tried to install the new ones upside down.

Duh. I deserve the flames....

But I am leaving this thread in hope that someone trying to change gaskets doesn't waste too much time going crazy. Even though they look symmetrical, they are not.

Thanks anyway,

Arman

 

Props for your honesty, but whenever you ask a technical question like this, more info is needed. In particular, list the year and engine type (DE vs. HR) in your Z to gain an answer.

 

The triangle cut out needs to point up and be close to the firewall, always use OEM Nissan multi-layer!

 

Can we all agree that this person is a beast for replacing the exhaust manifolds. I would be so frustrated trying to do that.

 

I had the exact same problem, exact! Did you get Tomei headers and they sent you HR gaskets? Some claim they fit but on my 2003 DE FX35 THEY DID NOT. Didn't matter what way I tried, so I cut the outside part of the gasket that wraps the bolt. I didn't compromise the gasket anywhere around the exhaust ports. No exhaust leaks.

A link to my thread where I write about this in detail with many pictures; https://www.infinitiscene.com/thread...230572/page-10
A diy from the same FX site where the guy installs some stillen headers: https://www.infinitiscene.com/thread...all-diy.38116/



Bottom right corner of new HR gasket refuses to line up with my old DE gasket.






Below is a snippet from my thread where I write about this issue. Taka Takanowa (iirc?) from Tomei didn't have a clue. Often times the people that should be in the know are totally ****ing clueless.

1st 2 pics show just how close some of these bolts come to the header. Some of the studs that came out with the bolts where put right back in the way they came out.
The next 3 pics are the old vs new gaskets, a shot of the Tomei passenger side prior to install and the old & busted off the FX.
The last 5 pics are of the passenger side gasket. Everything about the Tomei's are good quality imo, except this gasket. The bottom hole on the right side is so far off that the gasket would not fit. At first, I thought it was something I did wrong. I put the old gasket on and no problem then I installed the Tomei in every possible way thinking that they had the direction wrong in the directions. Nope. They ****ed this up. Pic 7 is the problem corner and pic 8 is on the other side and how it should look. I had to cut the corner to get it to fit.

Edit 3/23/18 - It's a little unnerving that the Tomei rep for the USA was told that the headers are supplied with DE and not HR gaskets, yet that is clearly not the case. It's really odd that only 1 bolt wouldn't line up and only on the passenger side. The hole located right above the problem hole looks sketchy but that one was fine.
Tomei's reply;
" Thank you for the link and I have forwarded it to our engineer in Japan. One thing that confuses us is that I was told that it is supplied with VQ35DE gaskets, and we have never had an incident with our gaskets.
Thank you for running our manifolds!
Best Regards,
Taka
TOMEI POWERED USA "

 

Thanks for the props, but I'm not done yet.

Wow! frustrating isn't the word... I got the both manifolds off. (And I thought that was going to be the hard part!). I got the gaskets on and managed to be able to get to all the nuts to tighten them. The passenger side was completely different. I can only get to 3 of the 6 nuts. For the record, I am using DC headers on an 04 DE motor. I will definitely have to remove the coolant tube to be able to get to the other nuts due to the shape and routing of the header tubes. Damn, I thought I would get it done.

Words for the next idiot that tries this.... RUN FAR AWAY! RUN NOW.... Pay someone to do it.


thanks,

Arman

 

Lol, you know, as much of a pain as it was to do headers as a mechanic I just can't justify paying someone to do a job that I can do better... Not for the faint of heart tho.

 

Soooo, I finished. Sort of. Been done for 2 weeks with the original job. Everything buttoned up. Pipes aren't exactly running exactly the same height on both sides, but it went together. So after I put it together, I decided to take it for a ride. Dropped it down to the ground and turn out of my driveway. As I turned, I felt the steering get tight and then pop. I broke the clock spring in the steering column. Another piece of advice to persons following this thread, don't get frustrated trying to put the steering shaft back on the rack and spin the steering wheel around several times in anger. I forgot that there was a clock spring and broke it. Also, I lost the chin spoiler on a fast drive because I didn't put the engine splash shield back on. I was too exciting to test the car. I noticed that the steering wheel is now cocked over about 10 degrees to the right. I even took the steering wheel off and tried to move it one tooth to the left, but then it was cocked about 10 degrees to the left. I checked the marks on the rack and shaft and they are lined up exactly. Not sure because when I bought the car, I commented on how nice it was to have a car that drove perfectly straight and had the steering wheel perfectly lined up.
I decided to take the advice of some and get it tuned. Shout out for Evans Tuning in Mount Bethel, PA for taking me in quickly. He did a baseline and came up with 256HP at the wheels. After the tune it was 272HP. Should equate to about 317HP at the flywheel. More than my last car, a LT1 C4 Corvette. I know he used REVUP software. There is only one tune for 93 octane. I have a base model without Cruise control and REVUP uses cruise control to switch maps. Beyond that, I am not sure of the actual map changes.
Today, I bought the clock spring and with the help of YouTube attempt to install it. Shouldn't be too difficult but in the end, a stupid ground hog cost me about $3000 in parts, new tools and a tune.

 

I think I have the same issue, which way does the oem gasket go with the flat side facing the head or the manifold