Topic: Solo Catless Downpipe - Not Impressed

[rotarypiston]

I just installed my Solo Catless Downpipe on my Solstice GXP with GM Stage 1, and needless to say, I am not impressed with the performance.

For the record, the piece is a quality 2.5 inch pipe and there are no leaks or problems with it.  Everything bolted up fine and works well as intended.  Great quality. 

This catless downpipe exhaust piece installed on Cobalt SS Turbo's has a big difference in power and feel.  It also has the LNF.  And with my brothers 09 Cobalt SS Turbo with GM stage 1 and catless, it definitely feels a lot more powerful with the new exhaust than without.  Same goes for my cousins 10 Cobalt SS Turbo with Trifecta tune and catless, feeling a lot more powerful with the new exhaust than without. 

Maybe it is because their systems are a true 3 inch downpipe to catback and ours are a 2 inch reducer where the catback bolts up.  I am not sure.  But the car literally just sounds like its a bit louder than actually more powerful.

At this point, I am debating on putting the stock downpipe back on because I am this unimpressed with its performance. 

Could a few of you chime in here if you know what the power gains are suppose to be with this catless downpipe with stock catback exhaust?  I would like to hear what others have to say about this.  Honestly, this is kind of depressing.   

[1LILNDN]

James   Give Solo a call before jumping the gun . They should be able to give you answers of what is or is not happening . They stand behind their products 100%

 I have the Solo Hi-Flow Cat and the Magnaflow 3" Catback Exhaust & very happy with it  . I have heard that some are using a long tube header W/ the catless pipe .

[IBDRINKEN]

On my old solstice that was stock I installed both the cat and their race exhaust. Then had it dynoed and it was an increase of 29 hp. I wish I could find the dyno sheet. I Could definitely tell that there was an improvement

[Gentleman Jack]

Rotary piston-

Don't jump off the bridge yet!!!!!!

It is 100% to do with the TUNE!!!!

In the Solstice / sky the ECM is not programmed to take advantage of any mods. An aftermarket tune will cure all your disappointment.
Let me know via PM if you want any more info, but I'm sure others will chime in.

[rotarypiston]

Rotary piston-

Don't jump off the bridge yet!!!!!!

It is 100% to do with the TUNE!!!!

In the Solstice / sky the ECM is not programmed to take advantage of any mods. An aftermarket tune will cure all your disappointment.
Let me know via PM if you want any more info, but I'm sure others will chime in.

I do have the GM Stage 1 kit.  My friend, my cousin, and my brother, ALL with the LNF, 2 with GM Stage 1, did not have this happen to them.   Most mods do not make a difference, but, the catless downpipe is 1 mod that actually sees gains, on stock cars or not from what I have seen.  But more info would be great if you want to elaborate because this is not what I have seen first hand happen before and also is not what I typically hear from other LNF owners alike.

[Kelu]

James, don't blame the cat-back system, I'm running Solo Mach Shorty which is 3" indeed but I could go pass 400hp with that, I don't think stock 2,5" cat-back is a restriction for aprox. 300hp. Definetly is larger than Cobalt imho.

Is interesting to hear that from you because Kenny just installed back the stock downpipe replacing Solo catless with GMPP tune and stock cat-back and he was amazed to feel the difference but in the other way.

How did you "measure" the performance? Buttdyno?

Here are my before & after dynos with Solo exhaust but I had Westers tune:
http://www.kappaperformance.com/forum/index.php/topic,3189.msg38639.html#msg38639

[DeepBlueGXP]

Need to reset your fuel trims, then you will feel the difference.  You are judging this from your butt dyno and the feel is different for rear wheel drive vice the balt front wheel drive.  Perhaps you need to update your butt dyno.  You can get a new one here
http://kalecoauto.com/index.php?main_page=product_info&products_id=8

[ihawk95]

Don't you have to update the tune for the car to take advantage of the better flow? My understanding is our cars are smart and will try to learn down to maintain the tune performance.

Am I kinda right on this?

[Kelu]

Yes you are right, but GMPP should, theoretically at least, get rid of that aspect

[Gentleman Jack]

Remove fuse 42? And 43??

The two fuses for the ECM. Wipe its brain of all short term info. See if that helps, but - get an aftermarket tune that can specifically take advantage of the down pipe. The cobalt is the cobalt and the sky / sol is the sky / sol. They may be the same engine, but the do not share the same brain.

[ihawk95]

Yes you are right, but GMPP should, theoretically at least, get rid of that aspect

I'm not as familiar with the gm tune, but it's still from gm. And they didn't offer much if anything in opening up airflow/exhaust flow through the cars.  I suspect it won't take full advantage of the better flow. I could be went though

[kwtoxman]

The forums have gone over the GM tune in detail ad nauseum. The learn-down is gone, while safety limits are still there for the turbo. There are a bazillion gm tune cars dynoing 275-300+ whp, when it alone is rated at 290 crank hp.

[ihawk95]

Forgive my ignorance since I'm not on the forums anymore except this one, don't own an lnf, and won't consider the gmpp tune when I do. My apologies

[elff]

Need to reset your fuel trims

This^^^^
Give it a couple of drive cycles

Also
Rwd is not FWD.  Even though the engines are the same, the power is put to the pavement in a completely different manner and feels completely different

[rotarypiston]

Need to reset your fuel trims, then you will feel the difference.  You are judging this from your butt dyno and the feel is different for rear wheel drive vice the balt front wheel drive.  Perhaps you need to update your butt dyno.  You can get a new one here
http://kalecoauto.com/index.php?main_page=product_info&products_id=8

I have not thought of this one.  I actually have an MSD Dashhawk and will be doing this today.  Resetting fuel trims is one thing the MSD Dashhawk can do.  I will try a few more drive cycles to see if it will eventually open up some more. 

RWD vs FWD feel is different I know, but my friend has a Saturn Sky Redline with GM Stage 1 and the catless when we installed it on his car just seemed to feel more powerful... Guess I need a new butt dyno like you said lol   

[Gentleman Jack]

Did you leave a shop rag in the down pipe?
It has happened... 

[rotarypiston]

Did you leave a shop rag in the down pipe?
It has happened... 

no shop rag 

Well I have the CEL for the O2 sensor in the rear that from my understanding does not effect engine performance, but, hear some others say it does.  Anyone have an O2 extender that works in preventing the CEL to trigger?  I am thinking of buying one of these 2 products below to try and fix that.

http://vibrantperformance.com/catalog/product_info.php?cPath=1022_1069&products_id=1604

http://shop.zzperformance.com/store/p/1237-02-Bung-Extender.aspx

Thoughts? Input?

[elff]

If you bought the Cat from Solo new, it should have included a steel extender.
If you did not receive one, give them a call
if you did not buy it new from solo
Give them a call and buy one from them so you know it will have the proper threads

[rotarypiston]

If you bought the Cat from Solo new, it should have included a steel extender.
If you did not receive one, give them a call
if you did not buy it new from solo
Give them a call and buy one from them so you know it will have the proper threads

did you have this problem?

edit:  I called them and they said with the catless ones they do not provide one because they say it won't fix the CEL

[IBDRINKEN]

did you have this problem?

edit:  I called them and they said with the catless ones they do not provide one because they say it won't fix the CEL

I used a spark plug spacer many years ago and it fixed it for me on my GXP

[elff]

Even though I read the title, I was assuming you had their hi-flow cat vs a complete open downpipe.
I did not realize they sold different ones.
I have a Hi-Flow with the extender and no longer get the engine code.

I would think the extender would still fix the issue as it pulls the O2 sensor out of the direct flow.

If not, you have no recourse but to turn off P0420 in the tune or deal with the Cel.
If you can turn off P0420, then you can also retune your car since you need a licensed copy of HPT to do so.
You are now on a slippery slope

[rotarypiston]

Well I added the Vibrant O2 extender with one spark plug extender.  Hope this works over the next couple days.

Here is a picture of what I did for reference.  I think it looks pretty good 

[elff]

That came out nice

let us know if it keeps the code away.

[rotarypiston]

That came out nice

let us know if it keeps the code away.

Tried the bung extender and it did not work initially.  Bought another bung extender from Vibrant and combined the two I had and the CEL still came on.  The code was bank 2 O2 sensor too lean.  I then took the one out and left the Vibrant one and we will see how that goes.  The car still feels underpowered to me and I still am not happy with the null performance gain I am getting. 

After tomorrow I probably will take it off and put the stock one back on.   

[elff]

I wonder if for your tune a hi flow cat would be better.  Sometimes some back presure is a good thing