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?
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? Absolutely !!
How will I know how far to turn it, if at all? I'm not sure, I think I did 1 1/2 turns on mine
Will I require a protune to run this piece? No, I run PDX stage 2 maps
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?
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.
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:
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.
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.
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.
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.
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?
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.
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.
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?
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:
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.
On the GrimmSpeed website, there is a $140.00 refundable core fee if I were to purchase the 06/07 ported/coated exhaust manifold and high flow crosspipe. As far as if they were going to straight up purchase your stock headers, you'd probably want to contact them directly to find out.
Thanks Chris. That's the exact spot I would have considered drilling/tapping if I were to do it myself, but I don't have a drill press, nor do I have any experience drilling/tapping anything (not that I doubt my abilities). My dad was telling me about his experience working on Mustangs back in the 60s/70s and he put a little fear in me as far as drilling into cast iron, mating different types of metals, expansion/contraction during heat cycles, only getting one chance to tap things properly, the risk of cross-threading, breaking a tap and having to drill it out, being without a car for a period of time - pretty much anything and everything that could possibly go wrong (hey, that's what dads are for, right?)... which is what got me thinking about the GS parts to avoid all of that potential trouble.
Thanks for the info about the DP bung - I had a suspicion that was the case, but I didn't look into it. Thanks for saving me some time. I knew the temp readings would be lower since it's several feet further away from the heat source, but I didn't realize it would be around several hundred degrees +/- (that makes sense though).
For now, I'll just hook up everything else for all the gauges and have an inactive EGT gauge with the sender unit/wire ziptied neatly in a coil somewhere in the engine bay near the driver's side exh-mani until I can get the GS pieces and do it properly.
As for wrapping/spraying over the flex-section of the GS crosspipe, is that an issue as far as limiting flexibility or does the wrap flex too? Even after being sprayed? I imagine the flex section would move around a bit as the engine vibrates during normal (and abnormal) driving similar to the flex section in the cat back... I wouldn't want to stiffen that up too much unnecessarily. Do you wrap everything except the flex section or is it ok to cover that up?
I've never wrapped/sprayed anything before, but that sounds like it would be doable given my attention to detail when it comes to those types of things. Obviously, the best option is probably to get the GS pieces ceramic coated and then wrap/spray them myself. I'm not too keen on the idea of reusing the stock heat shields if I can help it. I just don't like the look - not that anybody can see under there anyway. It's a mental thing.
I guess it's time to man up and drop another several hundred bucks
I have a deal with GS that I just ask them whenever I come across a set of elbows... Usually they buy them from me, but every now and then they're good on cores and don't need any. I think all in after my two cores I sent back I spent about $400 on pnp, crosspipe, egt tap, ceramic coating. Since then I've sent in 11 sets of elbows and made a couple hundred more.
If you buy a pnp set from them, yes they give you $140 back for your core. If you want to send extra sets they give you $80 per set. I've given them a good amount of cores, and as long as I can get the elbows for cheap enough I make $20-30 per set after shipping. I do the same thing with DW, but injectors I can usually double my money.
As for wrapping, don't wrap the flex joint. That keeps too much heat on it and will wear it out in quick order. Just make sure to soak the wrap in water, I like to use hose clamps to secure the ends, and wait for it to dry before you coat it. After I coat it I bake it on my grill rather than put it right on the car and heat it up that way... Pretty sure you're supposed to bake the spray, and doing it on the car is fine, I just prefer to get the smoking done on the patio than under my hood.
How I did my up-pipe (used the crappy straps that came with the wrap):
Awesome. After checking out a bunch of pics of the stock exhaust manifold, it looks like it would fairly difficult to wrap neatly/effectively. I could wrap the high flow crosspipe, but I also saw a temperature graph of stock headers vs. ceramic coated headers and there's a 100 + degree difference throughout the RPM range, so I think I'll be fine with the ceramic coating and leaving the stock heat shields off when I reinstall everything. The thick cast iron design of the ends + ceramic coating on everything should be plenty good for a dd - although I might end up changing my mind about wrapping the crosspipe at the last minute
F. There's always a catch. Bye bye $, hello horsies and EGT sensor.
Question: would the ceramic coating significantly increase the temp readings of the EGT sensor if it's installed on the driver's side casting button? I'm guessing probably not because the gases have only traveled several inches from the block - sorry, I think I answered my own stupid question.
The pipes would be ceramic coated inside and outside... I was just trying to make sense of why I would be paying for them to remove material (metal) from the inside of the pipes if they're just going to replace that with a different material (ceramic coating). I guess the thickness of metal removed is greater than the thickness of ceramic coating added = net gain of inner pipe diameter plus smoother flowing connections/surfaces = net gain overall. Nevermind.
Should I be concerned with the ceramic coating breaking off inside the mani and shooting through the hot side of the turbo and damaging the fins?
Just trying to cover my bases here. Thanks for being patient...
I don't think they coat the inside... Also don't think they port ALL the way through (forgot the company that does it ALL the way through). Ron (DumDum knows) of the technique I believe.
They actually do coat the inside, sort of. They really only get as far as it will spray in, so before the bends.
You can kind of see it in this picture.
Also, for the coating taking up removed material in terms of diameter... It's a very thin coating in the scheme of things. Even with the coating my pipe diameter went from this (just under 1 1/2"):
Thanks, yeah I'm still wondering about this too. I'm thinking that after a short period of time, a layer of black carbon/exhaust particles will form a coating on the inside of the pipe and will sort of seal any inner ceramic coating material in place. Now that I think about it, this probably isn't much of an issue.
I re-read the description on GrimmSpeed's website and they claim to remove about 6-7 mm of metal near the inlet/outlets so the thin layer of ceramic coating that replaces that is really probably negligible.
Thanks for the pics and info !Thumbs Up
I also emailed GrimmSpeed and they said new hardware would be provided, so I won't have to worry about that. Also, I can expect about a 2.5 week turn around on porting jobs, which isn't too big of a deal. I'm getting pretty excited now
Well, I guess some is better than none. I'll try to be really careful when I take everything apart. Worst case, I could pick some up at the dealership.
Extrudehone ... Found it in another thread. JR posted the name and I remembered.... hahaha
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