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-   -   Grimmspeed Ported Exhaust Manifold + High Flow Crosspipe? (http://www.wrxtuners.com/forums/f75/grimmspeed-ported-exhaust-manifold-high-flow-crosspipe-30561/)

man show 04-09-2011 12:36 PM

Grimmspeed Ported Exhaust Manifold + High Flow Crosspipe?
 
As I was reading up on how to install my EGT gauge, I began thinking... do I want to spend time wrestling with the rusted hardware and heat shields on my stock exhaust manifold, drill a hole in the driver's side pipe, spend money on new gaskets, and reinstall everything or do I want to buy Gimmspeed's ported exhaust manifold and high flow crosspipe and have that ceramic coated and pre-tapped for my EGT sensor? The answer sounds like a no-brainer, but I'm slightly concerned that I won't be able to use the Grimmspeed goodies safely with my OTS Cobb Stage 2 map. Grimmspeed's website says, "You may need to tighten your turbo wastegate arm because of the higher flow. Start by tightening the wastegate one full turn and then test where you are at. Repeat if necessary."

How will I know how far to turn it, if at all?

Will I require a protune to run this piece?

I'll probably also need to pick up some new bolts to attach the header - should I go to the dealership for them or can they be found at my local auto parts store?

wagonracer 04-09-2011 03:40 PM

[quote=man show;259435]do I want to buy Gimmspeed's ported exhaust manifold and high flow crosspipe and have that ceramic coated and pre-tapped for my EGT sensor? [COLOR="Red"]Absolutely !![/COLOR]

How will I know how far to turn it, if at all? [COLOR="Red"]I'm not sure, I think I did 1 1/2 turns on mine[/COLOR]

Will I require a protune to run this piece? [COLOR="Red"]No, I run PDX stage 2 maps[/COLOR]

I'll probably also need to pick up some new bolts to attach the header - should I go to the dealership for them or can they be found at my local auto parts store?

[COLOR="Red"]Only if you have a good parts or hardware store. Grummspeed provides good quality nuts and bolts for their piece, you might just ask them for the extras that you'll need.[/COLOR] [/quote]

Grimmspeed are definitely the good guys, give them the biz !Thumbs Up

turmic 04-09-2011 04:14 PM

Probably don't have to have a tune. But, if your stopping into IAG soon. Just let them make a custom map for it. Your car will love you for it. :D

brfatal 04-09-2011 10:36 PM

I wouldn't.

[url=http://www.clubwrx.net/forums/tuning-electronic-engine-management/134329353-protune-redo.html]Protune Redo[/url]

BLAZE2099 04-09-2011 11:11 PM

ohhh snap!!!! I guess its a matter of where you want your power, at least thats how I read sasquatches dilemma. Maybe I read it wrong tho, im gettin a bit tired:yawn:

turmic 04-10-2011 09:56 AM

Maybe Donkey ported too much. There is such a thing as doing too much. I haven't heard of GrimmSpeeds PNP causing this much rightward movement.

RcrsWetDream 04-10-2011 10:11 AM

I feel like my power comes on harder after the GS PnP & Crosspipe. I doubt I picked up any peak power but it came on harder and sooner.... That was just my butt dyno though, I don't have any actual results.

EDITED TO CLARIFY

turmic 04-10-2011 10:19 AM

Well, that does follow the old adage. Smaller pipes for more torque and bigger pipes for more hp. If its all you do for modification. Then you might loose some bottom end. But, if people are going to bitch about it. Then I don't understand why they're chasing HP numbers then.

brfatal 04-10-2011 11:40 PM

[quote=turmic;259486]Maybe Donkey ported too much. There is such a thing as doing too much. I haven't heard of GrimmSpeeds PNP causing this much rightward movement.[/quote]

Donkey (who is dumdum on here) redid his stock crosspipe and he liked those results better than Grimmspeed's. He attributes the problem specifically to that part because he said it went back to 'normal' after the new one was installed.

[quote]Donkey sent me an inlet ported OEM crosssover and I installed it on 4/30.

There are a couple of relatively steep hills in my commute. I have gone up them countless times and know how the WRX has performed on them very well. I seem to have most or all of my spool back. This is one butt dyno reading that is fairly accurate. [/quote]

turmic 04-11-2011 03:03 PM

You got me there Justin, I didn't read the whole thread. That is weird that the GS crossoverpipe threw off the motor worse than a OEM P&P. It was my understanding that GS used OEM pipes and just P&P'd them. Very weird. Maybe the 2.0L engines hate the GS product. Do you have any evidence that the 2.5L engines experienced the same thing?

RcrsWetDream 04-11-2011 03:46 PM

Edited my post above... Made it sound like my car spooled better before the PnP and crosspipe, but I meant the car felt better after the PnP/crosspipe.

I'd guess the 2.5L can move more air than the 2.0 that it can actually see the benefits of larger diameter exhaust piping.

I mean, the 08+ WRX use the EXACT SAME exhaust manifold as the 02-05's did (06-07 have their own screwey manifold that was different because of the crosspipe, ID is the same). How come Subaru didn't upsize when they went to 2.5L? Could be because the pipes were already big for the 2.0L to move air through.

GS uses OEM elbows for their PnP, but the crosspipe is 100% their design, no oem parts there.

man show 04-11-2011 08:29 PM

After discussing my gauge plans with my dad, he actually talked some sense into me and I decided I'm not going to drill/tap my own exhaust manifold because I really can't afford the down time without the car right now if I would damage anything. I'm going to wait and get the GS pieces when I have some extra money... that will be a project for another day. I'm still going to mount and wire up the EGT gauge for now though - hopefully this weekend, along with the other two.

Thanks a bunch for answering my first set of questions, but I have several more:

Is the ceramic coating worth getting or would I be better off wrapping and sealing everything with some high-temp spray myself - or both?

Where would they drill/tap the hole for the EGT sensor?

Would it be ok if I mounted the EGT sensor in my Cobb DP bung for the time being or should I just wait, buy the GS goodies and mount it properly?

How far off would the temp readings be if I mounted the sensor in my DP bung anyway - would that be a completely stupid thing to do? I guess I need to check and see if it would even fit at all.

Honestly, I mainly bought the EGT gauge for show, so I could really care less about how accurate the temp readings are, but later on down the road an accurate reading might come in handy. Should I forget the DP bung and just install it right the first time?

turmic 04-11-2011 08:58 PM

[quote=RcrsWetDream;259556]I mean, the 08+ WRX use the EXACT SAME exhaust manifold as the 02-05's did (06-07 have their own screwey manifold that was different because of the crosspipe, ID is the same). How come Subaru didn't upsize when they went to 2.5L? Could be because the pipes were already big for the 2.0L to move air through.

GS uses OEM elbows for their PnP, but the crosspipe is 100% their design, no oem parts there.[/quote]

Thanks for the insight Chris.

RcrsWetDream 04-11-2011 09:12 PM

EGT gauge is a 1/8 NTP thread, and the bung in the DP is about 2x the size (same size as O2 sensor on passenger side exhaust mani collector), so they won't fit. Temp readings would be useless in the downpipe, you only want to be a couple inches off the head. There I see temps in the 1400* range on extended pulls. In the downpipe that's probably below 1000*.

GS drills and taps the hole for the EGT on the drivers side collector. If you look at that side there is a "button" on the outisde of the elbow that is a raised 1/3" or so diameter circle. It's thicker and flat so they tap there.

Picture of GS tapped manifold vs stock untapped:

[IMG]http://img.photobucket.com/albums/v253/weeksifer/Exhaustmanifolds021.jpg[/IMG]

As for the coating, I have all three on the crosspipe, but the elbows are just coated with the stock heat shields on them... I couldn't tell you if the ceramic did anything, and the fact that I wrapped and sealed the crosspipe, I can't really feel much heat in front of the engine coming from the crosspipe.

synolimit 04-11-2011 09:55 PM

^^can i sell my stock headers? didnt GS pay you for some or something?


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