DIY ITB setup
01-19-2015, 02:41 PM
#1
Thread Starter
DIY ITB setup
Here are all the parts I used to install a set of OBX ITB's on my 2001 S2000. I did not use Amazon to purchase most of these but it provides a easy reference for all the parts. I suggest shopping around eBay, JEGS, Summit Racing, etc when hunting for the best deal.
I am including specialty tools in this list but if you have access to a shop then you might not need to purchase those obviously. However, the carb sync tool is really useful to own since you can easily check that your ITBs are sync'd whenever you want.
Some thoughts during my install:
1) use a M12x1.5 tap to rethread the ITB's water neck for the OEM coolant temp sensor, make sure the drill it out first
2) undo all the NPT fittings and apply quality pipe tape like this http://www.amazon.com/LA-CO-Slic-Tit.../dp/B004MYFPAK
this includes the 2 -6AN fittings on the fuel rail, all 8 vacuum elbows on the ITB and the vacuum block, 2 hose barbs for FPR and MAP sensor, the unused plugs on the vaccuum block, the coolant bleeder nipple, and the coolant water neck
3) put a 90 degree 1/4" NPT elbow on the front plug below the coolant bleeder and a 1/4" barb hose fitting to run a coolant line from there to the top of the thermostat housing circled here in red
to the manifold here
4) all that is needed to run stock injectors is to raise the OBX fuel rail like so
in addition you will need fatter injector orings, 1 for each injector at the top to seal the fuel rail. these can be purchased for auto parts store for less than $5
5) you can use the provided TPS or buy the OEM adapter from Jenvey. I used the adapter since it came with my ITBs
6) to get the throttle cable to the right length I removed this piece from the throttle linkage on the ITBs
doing so allowed me to position the linkage further away and let the throttles open fully
7) replace the OEM air temp sensor with a GM open air element sensor, the OEM sensor responds very slow compared to the GM sensor
8) when setting the FPR, unhook the vacuum line and start the engine. you want the fuel pressure gauge to read around 43psi with the vacuum disconnected.
9) I did not need the IACV to achieve good idle or cold start up. I set the warm idle to be ~1200rpm so when the fan kicks on or i put the AC on it dips to 1000ish
10) the OBX vacuum block is not too small for good brake pedal feel. I have ST40 calipers in the front and Wilwoods in the rear. pedal feels identical as it did before the install
11) some people used a Tube-to-AN adapter on the fuel return hard line. I was not able to get the 5/16th compression rings to seal on my AP1 fuel line. The compression fittings seemed to big and would always leak. I tried twice and gave up after spending an hour to gently remove the failed compression fitting. I ended up just using 2 hose clamps on a steel braided line. just position the clamps past each bump on the fuel line to seal them
12) using the UNI green foam (fine foam) cost ~20hp on the dyno
Before dyno, mods include 3" CAI, 3" Berk catless single, and AEM v1 EMS
After dyno, mods ITB, 70mm catless single, and Haltech EMS
Video
https://www.youtube.com/watch?v=T2lH8oanr4I
I built a box similar to this one with a sheet of aluminum from Lowes. it mounts to the little platform below the OEM IM for support
Part lists
all said and done it was about $1600 for everything including dyno tuning and a few hours of street tuning
I am including specialty tools in this list but if you have access to a shop then you might not need to purchase those obviously. However, the carb sync tool is really useful to own since you can easily check that your ITBs are sync'd whenever you want.
Some thoughts during my install:
1) use a M12x1.5 tap to rethread the ITB's water neck for the OEM coolant temp sensor, make sure the drill it out first
2) undo all the NPT fittings and apply quality pipe tape like this http://www.amazon.com/LA-CO-Slic-Tit.../dp/B004MYFPAK
this includes the 2 -6AN fittings on the fuel rail, all 8 vacuum elbows on the ITB and the vacuum block, 2 hose barbs for FPR and MAP sensor, the unused plugs on the vaccuum block, the coolant bleeder nipple, and the coolant water neck
3) put a 90 degree 1/4" NPT elbow on the front plug below the coolant bleeder and a 1/4" barb hose fitting to run a coolant line from there to the top of the thermostat housing circled here in red
to the manifold here
4) all that is needed to run stock injectors is to raise the OBX fuel rail like so
in addition you will need fatter injector orings, 1 for each injector at the top to seal the fuel rail. these can be purchased for auto parts store for less than $5
5) you can use the provided TPS or buy the OEM adapter from Jenvey. I used the adapter since it came with my ITBs
6) to get the throttle cable to the right length I removed this piece from the throttle linkage on the ITBs
doing so allowed me to position the linkage further away and let the throttles open fully
7) replace the OEM air temp sensor with a GM open air element sensor, the OEM sensor responds very slow compared to the GM sensor
8) when setting the FPR, unhook the vacuum line and start the engine. you want the fuel pressure gauge to read around 43psi with the vacuum disconnected.
9) I did not need the IACV to achieve good idle or cold start up. I set the warm idle to be ~1200rpm so when the fan kicks on or i put the AC on it dips to 1000ish
10) the OBX vacuum block is not too small for good brake pedal feel. I have ST40 calipers in the front and Wilwoods in the rear. pedal feels identical as it did before the install
11) some people used a Tube-to-AN adapter on the fuel return hard line. I was not able to get the 5/16th compression rings to seal on my AP1 fuel line. The compression fittings seemed to big and would always leak. I tried twice and gave up after spending an hour to gently remove the failed compression fitting. I ended up just using 2 hose clamps on a steel braided line. just position the clamps past each bump on the fuel line to seal them
12) using the UNI green foam (fine foam) cost ~20hp on the dyno
Before dyno, mods include 3" CAI, 3" Berk catless single, and AEM v1 EMS
After dyno, mods ITB, 70mm catless single, and Haltech EMS
Video
https://www.youtube.com/watch?v=T2lH8oanr4I
I built a box similar to this one with a sheet of aluminum from Lowes. it mounts to the little platform below the OEM IM for support
Part lists
Code:
OBX ITBs $800 OBX ITB http://www.amazon.com/gp/product/B00BI73IUI Sensors $22.99 GM open element IAT sensor http://www.amazon.com/gp/product/B005OS5G4S Fuel stuff $20 FBM fuel feed hard line adapter http://fullblownmotorsports.com/full...tock-feed-line $32.97 6 feet -6AN steel braided line http://www.amazon.com/Russell-632060.../dp/B000CPIJD8 $13.40 -6AN fuel gauge adpater http://www.amazon.com/Russell-670340.../dp/B000CPILAE $27.02 Aeromotive fuel gauge http://www.amazon.com/Aeromotive-156.../dp/B001O06BGM $155.99 Aeromotive FPR http://www.amazon.com/Aeromotive-131.../dp/B000CFSL1I $7.83 Aeromotive -6AN oring plug http://www.amazon.com/Aeromotive-156.../dp/B000F0YMUY $13.58 2x Aeromotive -6AN oring fittings http://www.amazon.com/Aeromotive-156.../dp/B000CFUP9O $11.23 45 degree -6AN fitting http://www.amazon.com/Russell-610090.../dp/B000CPAR9C - for FBM adapter to fuel rail $17.63 3x 90 degree -6AN fitting http://www.amazon.com/Russell-610160.../dp/B000CPIJ1A - for fuel rail to fuel feed hard line - for fuel rail to FPR - for FPR to fuel rail $9.79 straight -6AN fitting for http://www.amazon.com/Russell-610020.../dp/B000CPCNK8 - for FPR to fuel return hard line Tools $29.03 hose cutter http://www.amazon.com/gp/product/B006VU5WBA $6.37 M12x1.5 tap http://www.amazon.com/Uxcell-a121113.../dp/B00AUB7LGU $36.99 carb sync tool http://www.amazon.com/gp/product/B0007D20MQ Total $436.03 parts and tools, excluding ITB
Trending Topics
01-24-2015, 03:46 PM
#10
Thread Starter
Probably not worth the effort for a 2L, 52MM ITBs are too small even for the AP1
I am dreaming of an F24 with bored head and 60MM ITBs, those will probably be fun
Street driving needs a lot of tuning to get right. WOT driving is pretty easy to get right. Having a good tuner is critical.
Sounds amazing, like makes you smile every time amazing. All I hear is the engine now no exhaust which is nice.
Mid-range improved a shit ton but the top end still falls off, as you can see in the dyno 7.5K and the tq just falls.