Big Turb, CPE XcelXL MAF housing, CPE inlet pipe

[Speedie6]

Quick question. Going big turbo, I know that CPE makes an inlet pipe and a 3.25" MAF housing. But, the inlet pipe, while offerring a 4" turbo end, seems to only be 3" on the other end. At least that is what it seems from the product description on the CP-E site. I'm just wondering why it isn't 3.25" to match the XcelXL MAF housing?

I know that there are some guidelines as to how much power you can make based on the diameter of the MAF housing. Though, I don't happen to remember what those are. So, what are the stats of 3" vs. 3.25"?

I happen to have a currently unused ATP 3" MAF. I was thinking I might just use that and CPE's 4" to 3" inlet pipe if the XcelXL won't really do me much difference.

I am now built with new rods/pistons, I just haven't yet decided what turbo to go with.


P.S. What is the AFE filter part number that the XcelXL comes with? I might try to find a 3" version of it to use with my ATP MAF.

[SSinstaller]

The 3.25" MAF and flash is necessary tlo stop you from pegging the OEM MAF at higher boost levels...

[Speedie6]

Originally Posted by SSinstaller The 3.25" MAF and flash is necessary tlo stop you from pegging the OEM MAF at higher boost levels...

Yeah, I got that. The questions I had were, what's the power difference between 3" and 3.25"? I've got the ATP 3", and wondered what the difference in power limits between the two. Secondly, if 3.25" is necessary, shouldn't their inlet pipe for big turbos be 3.25" also? It doesn't seem to make sense to me to have a 3.25" MAF, to squeze it down to 3" and then balloon back to 4".

[spnkr21]

Just do it right the first time and get the stuff you need. 3.25 maf and flash.

[Speedie6]

Oh, and, by the way, the stock MAF housing is something like 2.62 or 2.65, I believe. The ATP according to my calipers is about 2.9" ID. So, the ATP is in the .25 to .3" bigger than stock. The CPE is, presumably something less than 3.25" ID, in order to use 3.25" hose, so, I presume about 3.15" ID or so.



AUTOMERGED FOLLOW-UP POST:

Originally Posted by spnkr21 Just do it right the first time and get the stuff you need. 3.25 maf and flash.

Well, I'm going to have it Cobb tuned.

My basic question here is, it doesn't seem to make sense to me that they made their BT inlet pipe 3" if their MAF housing is 3.25". So, if I use the CPE MAF, with their inlet pipe, then I'd need a 3.25" to 3" reducer which doesn't make sense to me.

[SSinstaller]

Originally Posted by Speedie6 Oh, and, by the way, the stock MAF housing is something like 2.62 or 2.65, I believe. The ATP according to my calipers is about 2.9" ID. So, the ATP is in the .25 to .3" bigger than stock. The CPE is, presumably something less than 3.25" ID, in order to use 3.25" hose, so, I presume about 3.15" ID or so. AUTOMERGED FOLLOW-UP POST: Well, I'm going to have it Cobb tuned. My basic question here is, it doesn't seem to make sense to me that they made their BT inlet pipe 3" if their MAF housing is 3.25". So, if I use the CPE MAF, with their inlet pipe, then I'd need a 3.25" to 3" reducer which doesn't make sense to me.

The CP-E big MAF is 3.5" OD and tapers to exactly 3.25" at the MAF...

The TIP is only 3" because it was made before the MAFXL, there is hardly enough room for the 3", going to 3.5" would necessitate moving the battery/ECM on the MS3, and not many are going to do that just for a big TIP...

[Speedie6]

Originally Posted by SSinstaller The CP-E big MAF is 3.5" OD and tapers to exactly 3.25" at the MAF...

Ah, thanks for the clarification. ATP rates theirs as 3" but that's OD, so, I was thinking that CPE's 3.25" figure was also OD. I presume that CPE's has an air straightener while the ATP does not. So, CPE's product is probably superior.

Originally Posted by SSinstaller The TIP is only 3" because it was made before the MAFXL, there is hardly enough room for the 3", going to 3.5" would necessitate moving the battery/ECM on the MS3, and not many are going to do that just for a big TIP...

Yes, 3.5" would be tight. But, you could go with a smaller battery instead of a battery relocate. And, I would think that at least some people, if they are already going to the trouble of going big turbo, and possibly also being built, if they've gone to that much trouble, would also do what is necessary to make the 3.5" intake fit. I guess I'm just saying that if they made the MAF that big, I'd think they'd make a TIP to match it.

But, I guess not. So, I guess that's that.

[SSinstaller]

Originally Posted by Speedie6 Ah, thanks for the clarification. ATP rates theirs as 3" but that's OD, so, I was thinking that CPE's 3.25" figure was also OD. I presume that CPE's has an air straightener while the ATP does not. So, CPE's product is probably superior. Yes, 3.5" would be tight. But, you could go with a smaller battery instead of a battery relocate. And, I would think that at least some people, if they are already going to the trouble of going big turbo, and possibly also being built, if they've gone to that much trouble, would also do what is necessary to make the 3.5" intake fit. I guess I'm just saying that if they made the MAF that big, I'd think they'd make a TIP to match it. But, I guess not. So, I guess that's that.

There is no air straightener in the CP-E MAF, but it was designed to be used with their flash and filter--most report fuel trims that are dead on or very close running the CP-E setup..

[xcoldricex]

Originally Posted by SSinstaller There is no air straightener in the CP-E MAF, but it was designed to be used with their flash and filter--most report fuel trims that are dead on or very close running the CP-E setup..

yeah there filter has a built in velocity stack so no need for a straightener.

[xcoldricex]

just get the 3.25 maf and call it a day.


hahaha, people just skim and don't read the question - i don't know the power limits of 3" vs. 3.25" - but if you're getting it cobb tuned you can't get the flash... but i'm pretty sure you can just calibrate your maf tables?

i'd just keep the atp if it's already 3in. because yeah, you'll have the 3" restriction anyway if you go with the cp-e combo.

alternatively you could make a new 3.25" inlet and slap on a 4" to 3.25" coupler, coupled with the XL intake- you were the one that made inlets before right?

[JumpingJackson]

If your going cobb just stick with the 3" ATP.

[Speedie6]

Originally Posted by xcoldricex alternatively you could make a new 3.25" inlet and slap on a 4" to 3.25" coupler, coupled with the XL intake- you were the one that made inlets before right?

Yeah, I used to make inlets. Once Cobb and CPE started making silicone ones, I stopped making my aluminum ones.

And, yeah, I could make a 3.25" if I wanted to. But it would be aluminum and I'm thinking I might as well just get CPE's silicone one. I'm just kinda baffled at why CPE made the inlet 3" and their MAF 3.25".

Originally Posted by JumpingJackson If your going cobb just stick with the 3" ATP.

I've already got an AP, and Cobb Tuning built my engine. So, yeah, I sticking with Cobb I think for the tuning. I know that CPE has had some breakthru that they are getting more power out of our cars than anybody else, but, I'm just not in the mood to switch teams. I do have a lot of CPE stuff, like towplate, DP, gaugepod, etc. And will get their inlet. But, I don't feel like switching to them for tuning at this point.

[xcoldricex]

i for one prefer aluminum TIPs... just because of the sound

[www.cp-e.com]

Good luck making power with that tune

Off to my wedding

[SSinstaller]

Originally Posted by www.cp-e.com Good luck making power with that tune Off to my wedding

Congrats!!! Er, I'm sorry???

However you want to take it...LOL

Wish you the best..

[Speedie6]

Originally Posted by www.cp-e.com Good luck making power with that tune Off to my wedding

Well, like I said, I've already kinda picked the Cobb horse for tuning. I understand you guys have found some stuff they haven't. But, I'm just not, at least for now, changing horses. I do have a lot of your stuff. I have the DP, tow plate and gauge pod.

Originally Posted by xcoldricex yeah there filter has a built in velocity stack so no need for a straightener.

Well, not sure about that. The Cobb SRI has a velocity stack and air straighter.

[www.cp-e.com]

Originally Posted by Speedie6 Well, like I said, I've already kinda picked the Cobb horse for tuning. I understand you guys have found some stuff they haven't. But, I'm just not, at least for now, changing horses. I do have a lot of your stuff. I have the DP, tow plate and gauge pod. Well, not sure about that. The Cobb SRI has a velocity stack and air straighter.

No worries - you'll make the switch if your turbo is of a decent size and then you don't make power. Cobb is a great company. They just haven't found the issue on this platform.

[senor blanco ms3]

Originally Posted by www.cp-e.com No worries - you'll make the switch if your turbo is of a decent size and then you don't make power. Cobb is a great company. They just haven't found the issue on this platform.

That's because the best person, IMO, that can tune a MS3/6 has yet to tune a BT car.

Speedie, I'm really looking forward to seeing what your car can do with a proper turbo. I was at Cobb when your car was on the dyno. There is a lot of potential there.