95mm throtle body--thinking "outside the box"
09-20-2008, 01:31 PM
#1
Member
Thread Starter
95mm throtle body--thinking "outside the box"
So I started thinking of a way to get a bigger air passage into the car with the minimum of expense and hassle.
the option avail right now---SL55 TB at 78mm as a swap. Some other board members have or are trying to use 90,95,100mm tb from other car makes (hemi"s) to our cars with limited success mostly due to the fact that MB has made our tb with 2 poitentiometers (ie the feedback is different). Other choices seem like they are going to be expensive---ie casting a new piece that fits on the Mb electronics.
So I came up with an "out of the box" solution that i feel will be very cheapand effective---Id like to hear feedback.
Basically, Id like to apply the same concept we use on the exhaust side of things to the intake side.
the idea------------------------> a Hole and electric cutout!
1-we leave the stock TB in place
2-we drill a hole into the mounting plate between the supercharger and the stock TB
3-attach a hose from the hole to an electric cutout type devise.
4-then attach another hose from the electric cutout to the air box.
5-wire the cutout using a throttle switch(like for NOS)
so when the car is driven 90% of the time everything is normal. as soon as you go full throttle-->the switch opens the cutout---->air bypasses the stock TB----> huge power increase----->HUGE GRIN!!!
as far as how big a hole......check out these rough calcs....
stock tb ------74mm----~4300 area
sl55 tb--------78mm----~4780 area
stock + 30mm hole-------~5300 area(acts like a 80mm tb)
stock + 50mm hole-------~7500 area(acts like a 90mm tb)
stock + 60mm hole-------~9100 area(acts like a 95mm tb)
one could start at 25mm and work up to see where the best tradeoff size is for our engines.
Seems pretty straight forward with lots of benefits.
a)easy to do (relatively)
b)easy to put back to stock
c)benefits only at full throttle...so everyday drivability is not affected.
d)low cost
the option avail right now---SL55 TB at 78mm as a swap. Some other board members have or are trying to use 90,95,100mm tb from other car makes (hemi"s) to our cars with limited success mostly due to the fact that MB has made our tb with 2 poitentiometers (ie the feedback is different). Other choices seem like they are going to be expensive---ie casting a new piece that fits on the Mb electronics.
So I came up with an "out of the box" solution that i feel will be very cheapand effective---Id like to hear feedback.
Basically, Id like to apply the same concept we use on the exhaust side of things to the intake side.
the idea------------------------> a Hole and electric cutout!
1-we leave the stock TB in place
2-we drill a hole into the mounting plate between the supercharger and the stock TB
3-attach a hose from the hole to an electric cutout type devise.
4-then attach another hose from the electric cutout to the air box.
5-wire the cutout using a throttle switch(like for NOS)
so when the car is driven 90% of the time everything is normal. as soon as you go full throttle-->the switch opens the cutout---->air bypasses the stock TB----> huge power increase----->HUGE GRIN!!!
as far as how big a hole......check out these rough calcs....
stock tb ------74mm----~4300 area
sl55 tb--------78mm----~4780 area
stock + 30mm hole-------~5300 area(acts like a 80mm tb)
stock + 50mm hole-------~7500 area(acts like a 90mm tb)
stock + 60mm hole-------~9100 area(acts like a 95mm tb)
one could start at 25mm and work up to see where the best tradeoff size is for our engines.
Seems pretty straight forward with lots of benefits.
a)easy to do (relatively)
b)easy to put back to stock
c)benefits only at full throttle...so everyday drivability is not affected.
d)low cost
09-20-2008, 02:09 PM
#2
MBWorld Fanatic!
Interesting BUT it would require software maps to work properly and deal with the rather abrupt transition from open to close. Too bad it would be so complicated to make it a "progressive" system.
There are actually many TB designs that have dual butterflies were the second one is progressive and they work great for their application (one where you need a disproportionate increase in airflow at full throttle).
There are actually many TB designs that have dual butterflies were the second one is progressive and they work great for their application (one where you need a disproportionate increase in airflow at full throttle).
