[parish8]

looking at my logs on hp tuners I see 98kpa at 2500rpm and wot and 93kpa at 6000rpm wot. that is about 10hp worth of manifold pressure being lost.

the filter and box top and tube all look decent to me. the bottom on the box is kinda tight and the chase from the front of the car seems a little tight.

has anyone tried opening up the bottom/side of the box at all? it would be a trade off, less restriction(maybe) for warmer air.

my only experience with this was a whipple on a truck with a stock air box. that thing picked up a decent amount of power by opening up the air box even sucking in warm air. another example was a procharger with the filter in a very hot spot right above the exhaust manifold. a CAI was built but it added a 90deg bend in a 4" pipe and a little pipe pre supercharger and it lost 10hp. both made more power with the hot air and less restriction.

another question does anyone have a log from an aftermarket CAI? can you look at the map reading from a wot low rpm point to a wot high rpm point?

[TSloper]

Parish you are spot on in your thinking here. Sadly it falls on deaf ears on this forum most of the time.

Yes there is a substantial pressure drop as the RPMs increase. The Rotofab does improve this by about 1kPa. I looked at this immediately after I installed the Rotofab. I logged the stock drop just before I installed the Rotofab unit.

The MSD intake improves the top end substantially also in terms of pressure drop.

A differential pressure meter places along the intake would tell you where the restrictions are.

[baf2000]

Finally someone thinking out of the box. So I was also thinking of removing the bottom of the stock air box, new one casot $80-90 . But also cutting through the plastic inner fender ( $100 ) to allow in cold air . Of course driving in the rain would then be ill-advised, but I bet the affect would be better air temp and lower pressure drop . Add a K&N filter and ya got cheap cold air .

[parish8]

Originally Posted by baf2000

Finally someone thinking out of the box. So I was also thinking of removing the bottom of the stock air box, new one casot $80-90 . But also cutting through the plastic inner fender ( $100 ) to allow in cold air . Of course driving in the rain would then be ill-advised, but I bet the affect would be better air temp and lower pressure drop . Add a K&N filter and ya got cheap cold air .

yeah, that would get some cold air in there. i might go a little less extreme and just open up the lower portion of the box to the engine compartment and see what that does. it would be easy enough to tape the holes shut and open the holes for a before and after dyno run. the box is mounted close to the inner fender. i wonder if there is any room to raise the box 1/2" or so? i am going to go out to the garage and check it out.

worst case is get a new box bottom, i would bet someone would sell their stock one after putting on a CAI for cheap.

[parish8]

i removed a portion of the fender side of the box. i was able to make a pretty decent sized hole that opens up toward the gap in the fender and toward the head light.

unfortunately i show the exact same 5kpa loss between the wot low rpm and wot high rpm.

[Roto-fab 1]

Originally Posted by parish8

i removed a portion of the fender side of the box. i was able to make a pretty decent sized hole that opens up toward the gap in the fender and toward the head light.

unfortunately i show the exact same 5kpa loss between the wot low rpm and wot high rpm.

Very innovative! That may point to the filter being a restriction. Your setup may help the performance of a drop-in filter. If you ever have any intake questions, I'll do what I can to help.

Have a great night!
Michael

[parish8]

Hmm. I will pull the filter and get another log. Thanks.

[TSloper]

Parish8,

Check out my first post here... http://www.camaro6.com/forums/showthread.php?t=443879

The second graph shows the MAP of stock vs MSD. You see there is a significant increase in MAP. This translated to a very big bump at the top end on the dyno. Peak HP didn't necessarily move dramatically but that drop we have form 6000 to 6500 came up 20-30 HP.

[TSloper]

Originally Posted by parish8

Hmm. I will pull the filter and get another log. Thanks.

Watch the MAF curve on that... I'm not saying it will screw up the readings but it might.

[PRAY]

Tim, are you thinking the restriction is coming from the Intake and TB and not the stock CAI. I know you saw what you liked with the Roto-fab. Have you been able to test with both the MSD and Roto fab yet?

[TSloper]

Originally Posted by PRAY

Tim, are you thinking the restriction is coming from the Intake and TB and not the stock CAI. I know you saw what you liked with the Roto-fab. Have you been able to test with both the MSD and Roto fab yet?

I have not tried the MSD and Rotofab together yet. I would expect to see some pretty good gains at the top end. The Rotofab showed a bump in MAP up to redline and the MSD intake did as well. That is about the best it is going to get short of H/C. I do think the TB may be a bit of a restriction as well. Porting it isn't going to help as the blade diameter is still unchanged. I'd love to see a TB somewhere between stock and the Katech unit.

I should have the following combo done within the next few months...

- E85
- MSD intake
- headers (probably 2")
- Rotofab

I don't think it will be possible to hit 500 RWTQ/HP (corrected) with just bolt ons but it will get close.

[PRAY]

I think you will come close. I just went back and looked at the dyno numbers from our C7 A8. With my ported TB/Intake, CFE CAI, 1 7/8" LT's and tune we put down 474/446rw. The car ran 11.1@125 with a bad trans and not the best weather. The plan was to go to E85 but the car was traded up for a C7Z this summer. I would say with E85 and the MSD you should be close.

I agree on the ported TB if you leave the blade bar alone. It is 12mm thick and I cut mine down to under 3mm thick. That gains me 154sqmm if I don't take into account the width of it which shouldn't matter. You are correct that there is no substitute for more throttle blade. Going to a 100mm blade gains you 1,500sqmm IIRC. I did the math a while ago. I think reshaping and blending the TB should gain you a bit (3-5rw) as well if there is an intake behind it that can use it. Behind the TB on the stock intake is pretty bad. I liken the TB porting to porting an intake runner of a head where you don't add cross section but make large gains in shape and taking out any useless material on the inside of the runner that is not needed. Like around the valve guide etc.

I sent you a PM on the testing I have coming up in a week or so. I will publish the results good or bad to inform the forums.

[parish8]

Originally Posted by TSloper

Watch the MAF curve on that... I'm not saying it will screw up the readings but it might.

hmm. now that you mention after i cut a hole in the box my a/f ratio is now reading about 1/2 a point richer at wot. i just started tuning it yesterday. i am not sure if it is normal for it to float around a little or if there is some kind of a modifier kicking in but before and after my eq commanded is the same so i don't think it is a modifier.

[PRAY]

A buddy of mine pulled the stock filter on the dyno to see what would happen and he said it richened up significantly. What did your MAF hrtz go to with the hole? I know you MAP didn't change but if the restriction is in the intake/TB as possibly suggested all the new air could be effecting the MAF. I would assume leaning it back out to what you are commanding could show some power on a dyno.