Primary 200 cells downpipes - is this a difference?

[Corleone1]

Hi guys!

This thread is for you that have experience from better primary down-pipes, with 200 cells or without. I hope we can discuss pros and cons, results, Dynos with or without.

I did have 200 cells with my old engine but when KIA did change and I got a new 2022 engine the put back stock primaries. With old engine I felt that rpm 4500-6000 went faster and better but it also hard to remember. Good low back-pressure always increase power and response and I have seen some Dyno proofs of like 25-30 awhp, that of course is when you boost more like 20-21 psi and where it deepens more compared to stock.

If you know some of this I have these Q and be grateful for you experience and response to this:

1. Do you have a Dyno from stock compared to bigger/better DP´s?
2. What is your drive feelings compared to stock?
3. Did 200 cells with no secondary pass yearly inspection?
4. Did cat less DP´s with secondary cats pass yearly inspection?
5. Is it worth it?
6. Which vendor has the best 200 C or full cat less ones?

Thanks from Sweden

 

[STINGER]

Hi guys!

This thread is for you that have experience from better primary down-pipes, with 200 cells or without. I hope we can discuss pros and cons, results, Dynos with or without.

I did have 200 cells with my old engine but when KIA did change and I got a new 2022 engine the put back stock primaries. With old engine I felt that rpm 4500-6000 went faster and better but it also hard to remember. Good low back-pressure always increase power and response and I have seen some Dyno proofs of like 25-30 awhp, that of course is when you boost more like 20-21 psi and where it deepens more compared to stock.

If you know some of this I have these Q and be grateful for you experience and response to this:

1. Do you have a Dyno from stock compared to bigger/better DP´s?
2. What is your drive feelings compared to stock?
3. Did 200 cells with no secondary pass yearly inspection?
4. Did cat less DP´s with secondary cats pass yearly inspection?
5. Is it worth it?
6. Which vendor has the best 200 C or full cat less ones?

Thanks from Sweden

I went catless primary & secondary at first and hated it, the sound was too much and rasp was crazy. Added HJS 200's to my secondarys and the car drives and sounds perfect. Performance is better than stock but I can't quantify, butt dyno says maybe 10-15hp in some areas.

 

[Corleone1]

I went catless primary & secondary at first and hated it, the sound was too much and rasp was crazy. Added HJS 200's to my secondarys and the car drives and sounds perfect. Performance is better than stock but I can't quantify, butt dyno says maybe 10-15hp in some areas.

Ok, so where did you get the HJS secondarys? I think of do the same if it will pass yearly inspection. Did you need to exclude the P420 codes in ECU.

 

[djerickd]

subd

 

[STINGER]

Ok, so where did you get the HJS secondarys? I think of do the same if it will pass yearly inspection. Did you need to exclude the P420 codes in ECU.

I bought the universal HJS cats, L=232 D=108 IN/OUT=63.5 CPSI=200 Part#90950072. They are not cheap, but HJS are the best performing cats in the market and they last a very long time, I've had mine for 5 years now.

I welded the cats onto my catless JUN secondaries.

I used a O2 sensor extension from day one, so I don't know if it would have thrown the code without them.

Note - most cats are directional, so make sure you put them the right direction.

 

[Corleone1]

Sounds good. Do you pass yearly with this place of cats? Do you also have second Lambda sond after the HLS?

I thought of a solution just like that also. To have them more back is always better as the exhaust temp lowers a lot first meter that helps backpressure.
I have done a lot of driving tests now with like 10 psi straight, 19, 18 and 17 psi. All over 18 makes car slower and its all about backpressure that has a limit where power goes down with more boost. To have as small backpressure as possible with stock turbos is better downpipes but also that some exhasut can travel thruu wastegate also. I think that more boost will fools most people, it can feel more with more respons/maybe some wheelspin (due to more instant tourque at midrange) but at wot if you chasing times it´s better to lower boost for a faster car.

I think I am going for 2.75" DP;s and have HLS more back in system.

 

[Corleone1]

Sorry, forgot... Do you have äny pictures of your secondary with HLS? Easier to see then how much free space it is. Thanks!

 

[STINGER]

Sorry, forgot... Do you have äny pictures of your secondary with HLS? Easier to see then how much free space it is. Thanks!

Other than the two pics I already posted, I have this pic. Its fitted at the very beginning of the secondary and clearance is fine.

 

[Corleone1]

Good to see, thanks. That will help my decesion. I think I go for this, releves much stress on engine.

Great to have you help here!

 

[STINGER]

Good to see, thanks. That will help my decesion. I think I go for this, releves much stress on engine.

Great to have you help here!

All the best