Any Ideas on expanding CFM of Kenne Bell 2.6LC Intake Plenum to 1300cfm
11-25-2012, 10:59 PM
#11
I finally decided it was cold enough to take the supercharger off. The intake plenum on the Kenne Bell 2.6 is a really nice piece. Too bad it goes from over 14" of area from the throttle body, down to 10.2" of area where the plenum curves towards the back of the supercharger.
I am guessing Kenne Bell did this so no one would have to modify the firewall.
I gained about 3/4" on the firewall with light massaging. You just have to watch for the wiper arm. Another 1/8" to 1/4" is available with some trimming of the arm.
We are going to cut out the back of the plenum and weld in some 1/8" to make the opening from 10.1" to about 13" of area.
We are hoping for 2 things. One is to get to the top potenial of the 2.6 easier and to maybe lower intake temps a little.
I am hoping to have the car back together within 2 weeks and I will see what the A/F ratio looks like.
Too big of a plenum would be a waste as well because I have been told the 2.6 handles up to about 1250 cfm.
The 90mm mass air and 4" intake tube may be a restriction at around 625 rwhp.
I am guessing Kenne Bell did this so no one would have to modify the firewall.
I gained about 3/4" on the firewall with light massaging. You just have to watch for the wiper arm. Another 1/8" to 1/4" is available with some trimming of the arm.
We are going to cut out the back of the plenum and weld in some 1/8" to make the opening from 10.1" to about 13" of area.
We are hoping for 2 things. One is to get to the top potenial of the 2.6 easier and to maybe lower intake temps a little.
I am hoping to have the car back together within 2 weeks and I will see what the A/F ratio looks like.
Too big of a plenum would be a waste as well because I have been told the 2.6 handles up to about 1250 cfm.
The 90mm mass air and 4" intake tube may be a restriction at around 625 rwhp.
11-29-2012, 01:21 AM
#14
I will be installing the modified plenum early next week. If I run leaner, then it worked.
I am not expecting IAT's to go down either.
I will post my findings.
I am not expecting IAT's to go down either.
I will post my findings.
12-02-2012, 11:51 PM
#15
It is all finished. The opening where it turns into the supercharger is 25% larger now. I should have it running by the end of next weekend. I am also fitting the Blow by racing methanol plate in at the same time...
12-15-2012, 12:36 AM
#18
5th Gear Member
Join Date: May 2007
Location: Central Texas
Posts: 2,388
Nice work! I'm curious as to the results you see.
I too am using a 4" pipe now for the intake, through the big kb monoblade TB, and BBR methanol plate under the blower. (if you need longer bolts for securing to the blower, I have an extra set). Using the larger inlet pipe caused a change in my afr/air flow characteristics as well. IATs, however, have remained high. Hence, now using methanol to help keep them down under WOT.
With the 1" change in height from the methanol plate, the room behind and above the blower changes quite a bit, and with a stock hood, I'm not sure it'd still fit.
There's have been similar projects documented on s197forum.com, including some custom plenums. Nonetheless, I'd like to see such modified intakes and how well they work and help.
(my pipe)
I too am using a 4" pipe now for the intake, through the big kb monoblade TB, and BBR methanol plate under the blower. (if you need longer bolts for securing to the blower, I have an extra set). Using the larger inlet pipe caused a change in my afr/air flow characteristics as well. IATs, however, have remained high. Hence, now using methanol to help keep them down under WOT.
With the 1" change in height from the methanol plate, the room behind and above the blower changes quite a bit, and with a stock hood, I'm not sure it'd still fit.
There's have been similar projects documented on s197forum.com, including some custom plenums. Nonetheless, I'd like to see such modified intakes and how well they work and help.
(my pipe)
Last edited by tx_zstang; 12-15-2012 at 12:38 AM.
12-15-2012, 09:38 AM
#19
Finally drove the car yesterday. My air fuel went from 11.1 to 11.3. It used to sometimes go to 11.0 and it disnt drop below 11.3 at all.
I put a temp sender right after the throttle body. It's amazing how hot the air gets at idle after only a few minutes. It was 49 degrees yesterday and it goes up to 95 degrees. I am guessing it is the combination of the recirculated bypassed hot compressed air and of course air flow of a static car.
I also noticed an unexpected result. My boost comes on quicker than before. Light throttle bring me to about 5 lbs. It was something I always questioned with kenne Bell. They though my bypass valve was broken.
It is really hard to tell if helped with iats. I do know that it was 49 degrees yesterday and my iats were 110 without my hx fans and 100 to 102 with them. I am not sure if iats have an exponential component when ambient temperatures rise, but I was consistently 70 degrees over ambient temp at the minimum even in 40 degree weather.
In conclusion I noticed .02 points increase in afr and quicker boost response.
I put a temp sender right after the throttle body. It's amazing how hot the air gets at idle after only a few minutes. It was 49 degrees yesterday and it goes up to 95 degrees. I am guessing it is the combination of the recirculated bypassed hot compressed air and of course air flow of a static car.
I also noticed an unexpected result. My boost comes on quicker than before. Light throttle bring me to about 5 lbs. It was something I always questioned with kenne Bell. They though my bypass valve was broken.
It is really hard to tell if helped with iats. I do know that it was 49 degrees yesterday and my iats were 110 without my hx fans and 100 to 102 with them. I am not sure if iats have an exponential component when ambient temperatures rise, but I was consistently 70 degrees over ambient temp at the minimum even in 40 degree weather.
In conclusion I noticed .02 points increase in afr and quicker boost response.