LTFT Values after Header install (ticking/Leak?)
 

So I've been hearing a small tick noise on the right side of the engine after installing my JDL catless UEL headers. Im suspecting it might be a small leak where the over pipe is or near the header flange.

Before I installed the headers I contacted JDL about the header flanges being a little off when I was testing them for straightness on a glass table where the flanges didn't sit flush on the table. JDL responded saying:

"Jay,

It is not uncommon when placing both flanges on something like a piece of glass to see some variation from side to side between flanges. These headers are not rigid in a manner that will prevent them from pulling to the heads correctly when being torqued. This will also have no adverse effect with added stress. Once the header has been heat cycled a few times everything will settle into place and it is a good idea to re-check your torque. The important part is making sure that the proper torque sequence is used during this stage of install. We prefer the OEM gaskets for the header to heads over the multi-layer steel ones as they are more forgiving to improper install/torque variations.

The header needs to be lifted to the heads and the center nuts run on by hand. Just hand tighten them, then move on to the outer nuts. Once the header is closed up to the heads hand tight you will begin the actual torque sequence which is as follows:

-Start with center nuts (does not matter which bank), torque to 25lb/ft.
-Move to outer nuts and torque to 25lb/ft. in a criss-cross method bank to bank.
-Once all 6 have been torqued, start at the center nuts again and torque to 35lb/ft.
-Move to the outer nuts and torque to 35lb/ft. in a criss-cross method bank to bank
-You can run through all 6 again if you like just to be certain you didn't miss one.
-Then proceed to your outlet flange, it is your preference which 2-bolt gasket you use but the supplied gasket will be more forgiving to improper seating compared to the steel layers OEM gasket.

Best regards,

JDL Auto Design Team"


JDL was very helpful in giving me detailed instructions on installing the headers, and I did exactly what they recommended. But from what I've read on the forums that torque values are 22ft/lbs.

The tick isn't loud, but its there. Maybe I'm just starting to hear things, I don't know.

I probably didn't do a good log but here's one i did today while driving to work. Does everything look normal? btw sorry I'm a noob at using OFT and all this tuning stuff.
https://datazap.me/u/jaivee/ltft2?log=0&data=1-11

If there is a leak at the headers your fuel trims would likely be much higher than what you are seeing in this log. Usually at low rpm and idle speeds. It doesn't hurt to double check things after installation and a few heat cycles, and then again ever so often.

thanks for the quick reply!

So the fuel trims look normal? I've seen some data logs similar to mine, and some that are mostly at 0.

I'll be under the car in a few days to install a catback and I'll re-tighten everything. But should I go with the torque values JDL recommended? And before re-tightening, should I wait before the engine and exhaust have cooled completely?

Yup! +- 5% LTFT is not ideal but pretty normal.

I had no idea there was a procedure for bolting on a header. Guess I got lucky I don't have any leaks! :D

You often hear ticking/whooshing noises after installing aftermarket headers its just the way most sound. I suspect the thinner wall material or lack of heat shields on aftermarkey headers is cause, sounds normal. As above if you had significant leak the ltft would be 10% or higher in most cases

Well, you should follow some sort of tightening sequence and torque specs to make sure the load is evenly distributed, but if it dont leak it dont leak lol

Thanks everyone for the input. I will just re-tighten everything again when i get back under the car. Good to know everything is within spec :)

Its generally just a good mechanical practice for any flanged connection to use a star/crossing pattern, and incremental torque in order to spread the torque load evenly on the whole flange.

Yes sometimes it is these small details that we are not aware. This is a reason my dealer does most of my installations.

And often enough dealers have no clue how to deal with anything non-stock that have no documented procedures in their systems, making it preferable to do in some performance shops and alikes, even while they may be not specialised with specific model or brand of car. For example that was the case with performance alignment for me. Dealer overcharged and did several mistakes. Hence from then on i did alignment/suspension work at performance shop that often deals with non-stock aftermarket parts, leaving dealership only for regular due maintenance and warranty tasks.

Totally agree, it depends the work. I went once to install my coilovers and told me that he could not do it. Then I went to a performance shop as you said. It depends the dealer and you need to find a good one and have a good relationship and trust.

I didn’t put my JDL UEL on in any particular pattern or even torque it and I have no leaks. Guess I got lucky too.

Just an update, I went back under the car today to install my invidia Gemini catback and checked the headers and over pipe for leaking and couldn’t find any, retorqued everything just to make sure and everything was tight :) I guess it’s just normal sounds that come from a catless uel header.

Btw the invidia Gemini sounds amazing with Jdl uel headers. It’s the deepest sound I’ve heard come out of an exhaust. But checking the catback for leaks I found every single one of the gaskets leaking! But I fixed that with copper rvt. I’m never gunna install exhaust parts without copper rvt, the stuff is amazing!