Hi everyone,

First post for me here and I'm looking for information regarding what to get as I'm planning on doing a Stage 1 Upgrade (approximately 380hk/480Nm) on my more or less stock EVO 9. I'm currently running Tomei Full Titanium Expreme TI.

What I need for my Stage 1 Upgrade:
- Downpipe
- De-Cat (test pipe)

The rest has already been installed.

My original plan was to go with Tomei's Downpipe and De-Cat (test pipe) but the company that will help me do the whole upgrade said that there are a few "issues" with Tomei.
1. With Tomei's Downpipe you have to change the elbow which could be a time consuming job. Since I will be running the stock turbo, the elbow won't make any difference.
2. The O2-sensor is located on the wrong side of the downpipe, meaning the cable won't be long enough. I could drill a new hole and weld it but that will obviously cost some money as well.

I liked the idea of going with a full Tomei System, I'm really pleased with the quality and the sound is amazing. But I guess it will just be easier to find something where the O2 sensor has a better location. I see a few brands have it located on the De-Cat (test pipe).

The company recommended me to go with:
- Mongoose 3" Downpipe
- Mongoose De-Cat

Downpipe

De-Cat (test pipe)


They mean it's a affordable setup and will do the job just as good since the Stage 1 upgrade (in terms of Hk/Nm) doesn't require the most extreme parts.

So the last few days I have been trying to do some research on Mongoose but it's quite hard to find. I'm not sure if they are common in the US but from what I've read on reddit, they seem to be quite popular in the UK.

From my research here on the forums, and reading other threads where people asks what downpipe to get, I've seen:
- HKS
- AMS
- Megan Racing
- Invidia

I do want to invest in high quality and parts that will fit OEM housings so I don't have to change the elbow.

Does anyone here have any experience with Mongoose in terms of quality and fitment?

HKS have always delivered I guess, but It doesn't seem to be as easy to get your hands on the HKS GT Downpipe and HKS De-Cat (test pipe) these days (I'm living in Sweden).

I don't know too much about Megan Racing and Invidia but quality seems to be good.

Any information would be helpful, thank you!

 

https://stmtuned.com/products/stm-re...-combo-evo-8-9

We have Emissions over here so you won't find test pipes as readily available but this is an extremely high quality 02 eliminator, and is very effective with a true 3" outlet the entire way through rather than a bottle neck at the turbine.

 

I use megan, fitment is perfect. just bought it again the 2nd time. Our local tuner just add their own o2 bung for the tuning session and it looks fine

 

Id go with HKS their quality and fitment cant be beat. But I will say megan products do not disappoint. I don't even know how they produce their stuff for so cheap and still make a profit.

 

I stay away from paying the "JDM" premium. downpipes just cook oil drips lol I need to figure out what cleaner to use

 

you need to take care of those oil drips! haha. I agree though I had a Megan on my old evo and it worked great they even offered the extended one with cat delete but not anymore probably due to regulations. I’ve got hks now but that’s because my whole car is of Japanese brands. SARD, greddy, tomei, carbing, ralliart, ect…So it only makes sense to shell out the cash of the rest of the car is consistently “jdm”

 

Any update with the project, how is everything going?

 

Nothing as of now. Still doing some research. Would like to get some more information about Mongoose before comitting to their downpipe and testpipe