FS: 1.8BP Custom Made ITB Setup
This is a custom made setup I created for my previous car (03 MSP with 1.8BP swap).
I got the car running on this manifold when I first did the 1.8bp swap into my 2003 MSP and was running n/a, however I never got around to building a proper plenum or finishing this setup "nicely".
The setup is not complete and will require several hours of tinkering to make it safe/reliabile enough to use daily.
What I am selling:
-custom aluminium 1.8 BP Intake manifold flange with ported runners welded on specifically for these GSXR Individual Throttle Bodies.
-4 GSXR throttle bodies
-8 t bolt clamps
-4 silicone couplings cut to fit (these connect the runners to the ITBs)
-GSXR TPS - Needed for Tuning Alpha-N - Works with MegaSquirt
-GSXR Idle Adjustment cable
(fits regular BP FWD head or AWD GTX, GTR head. NOT the 99+ miata heads)
When I ran these in my 03 the throttle cable fit right in the little hole, and actually fit in the bracket pretty good. Depending on your year/make you may need to make your own bracket (probably easiest part of the install).
The buyer must understand that this is not a setup for an amateur tuner / newb.
You must have an excellent understanding of engine management and what the tuning requirements are for an ITB setup like this and what must be done to make them work safely/reliably.
What is left to do:
1. The stock linkage between the throttle bodies had to be bent a bit to fit the new cylinder spacing. when this was done the little springs that hold everything in place did not work well and often fell out. I will include them but recommend something more reliable.
I installed my own little spacers that were held together via metal zip ties (typically used on exhaust wrap) to get my vac & throttle position evenly distributed between cylinders. I am not including these as they are not technically "safe".
I have seen others braze/tack weld the linkages at this point (once synced) so that they cannot come apart, however if you do that they can no longer be adjusted so I would look for a better solution.
My plan was to drill/thread a small hole between each one which could then allow adjustment between each linkage with a screw, similar to adjusting an idle screw.
2. The setup should have some velocity stacks added if you are staying n/a (the length/diameter/trumpet size etc. will vary depending on your setup / target powerband)
OR
The setup should have a plenum added (with internal velocity stacks if you have the time/cash) to be used with boost, or to be used n/a with a VAF.
Using the setup with a plenum and VAF (even when n/a) may actually make tuning substanically easier / more accurate.
3. Once you have everything position properly a mounting plate that connects all the throttle bodies should be installed to keep them in place and prevent any flexing/movement of the setup. This is the easiest part of the install. requires 1 skinny metal piece with some holes drilled in it. then put some small bolts through the plates into the throttle bodies (the threaded holes are already there) the to secure them in place. the stock GSXR piece does not work as the spacing between the throttle bodies has changed. this should cost you less than $5 and 1 hour of time or less.
You will also want to pickup some low profile nuts for screwing the flange on to the head bolts.
I used a MAP sensor to tune (combining the vac signal for each throttle to a collector with 1 way valves so that they dont steal each others vac, and then into a fuel filter (to help minimize signal spikes)) and
fed my MegaSquirts 4 bar MAP sensor. I used a second larger line with 1 way vales to connect to a custom brake booster vac resovoir (not included) so that the cars brakes still worked.
The setup worked well enough to drive around however I never got to the point of aggressively tuning the setup with Alpha N (which uses TPS signals as well) before I removed the manifold and started working on my turbo setup.
As simple as it sounds/looks it took quite alot of effort to get the flange/runner piece made properly and get this setup to the point where it is now.
I am looking for 300USD OBO + Shipping from Canada (I am in Ontario near Toronto) for everything pictured which is less than I have invested in the setup not even counting all the time I had into the project.
I am not in a rush to sell so hold off on super low ball offers.
I am only considering buyers that understand the challenge they are taking on with a setup like this.
I have a life and I am not around to provide you with tuning instructions / customer support so if you do not have enough knowledge/experience/time on your hands to figure out the setup and how to properly tune for the setup then this manifold is not for you.
Now that I am down to only 1 Mazda I do not check message board very often so if you have questions on how to do things I am not the guy you should be asking.
mx-3_4evr has a good write up on on clubprotege for putting together this custom setup and there is plenty of good general "custom itb tuning" info all over the internet.
If you are someone with an excellent understanding of how tuning and EMS work and have the time and fabrication skills required to finish the setup than please feel free to make an offer.
Thanks, Jeff
This is a custom made setup I created for my previous car (03 MSP with 1.8BP swap).
I got the car running on this manifold when I first did the 1.8bp swap into my 2003 MSP and was running n/a, however I never got around to building a proper plenum or finishing this setup "nicely".
The setup is not complete and will require several hours of tinkering to make it safe/reliabile enough to use daily.
What I am selling:
-custom aluminium 1.8 BP Intake manifold flange with ported runners welded on specifically for these GSXR Individual Throttle Bodies.
-4 GSXR throttle bodies
-8 t bolt clamps
-4 silicone couplings cut to fit (these connect the runners to the ITBs)
-GSXR TPS - Needed for Tuning Alpha-N - Works with MegaSquirt
-GSXR Idle Adjustment cable
(fits regular BP FWD head or AWD GTX, GTR head. NOT the 99+ miata heads)
When I ran these in my 03 the throttle cable fit right in the little hole, and actually fit in the bracket pretty good. Depending on your year/make you may need to make your own bracket (probably easiest part of the install).
The buyer must understand that this is not a setup for an amateur tuner / newb.
You must have an excellent understanding of engine management and what the tuning requirements are for an ITB setup like this and what must be done to make them work safely/reliably.
What is left to do:
1. The stock linkage between the throttle bodies had to be bent a bit to fit the new cylinder spacing. when this was done the little springs that hold everything in place did not work well and often fell out. I will include them but recommend something more reliable.
I installed my own little spacers that were held together via metal zip ties (typically used on exhaust wrap) to get my vac & throttle position evenly distributed between cylinders. I am not including these as they are not technically "safe".
I have seen others braze/tack weld the linkages at this point (once synced) so that they cannot come apart, however if you do that they can no longer be adjusted so I would look for a better solution.
My plan was to drill/thread a small hole between each one which could then allow adjustment between each linkage with a screw, similar to adjusting an idle screw.
2. The setup should have some velocity stacks added if you are staying n/a (the length/diameter/trumpet size etc. will vary depending on your setup / target powerband)
OR
The setup should have a plenum added (with internal velocity stacks if you have the time/cash) to be used with boost, or to be used n/a with a VAF.
Using the setup with a plenum and VAF (even when n/a) may actually make tuning substanically easier / more accurate.
3. Once you have everything position properly a mounting plate that connects all the throttle bodies should be installed to keep them in place and prevent any flexing/movement of the setup. This is the easiest part of the install. requires 1 skinny metal piece with some holes drilled in it. then put some small bolts through the plates into the throttle bodies (the threaded holes are already there) the to secure them in place. the stock GSXR piece does not work as the spacing between the throttle bodies has changed. this should cost you less than $5 and 1 hour of time or less.
You will also want to pickup some low profile nuts for screwing the flange on to the head bolts.
I used a MAP sensor to tune (combining the vac signal for each throttle to a collector with 1 way valves so that they dont steal each others vac, and then into a fuel filter (to help minimize signal spikes)) and
fed my MegaSquirts 4 bar MAP sensor. I used a second larger line with 1 way vales to connect to a custom brake booster vac resovoir (not included) so that the cars brakes still worked.
The setup worked well enough to drive around however I never got to the point of aggressively tuning the setup with Alpha N (which uses TPS signals as well) before I removed the manifold and started working on my turbo setup.
As simple as it sounds/looks it took quite alot of effort to get the flange/runner piece made properly and get this setup to the point where it is now.
I am looking for 300USD OBO + Shipping from Canada (I am in Ontario near Toronto) for everything pictured which is less than I have invested in the setup not even counting all the time I had into the project.
I am not in a rush to sell so hold off on super low ball offers.
I am only considering buyers that understand the challenge they are taking on with a setup like this.
I have a life and I am not around to provide you with tuning instructions / customer support so if you do not have enough knowledge/experience/time on your hands to figure out the setup and how to properly tune for the setup then this manifold is not for you.
Now that I am down to only 1 Mazda I do not check message board very often so if you have questions on how to do things I am not the guy you should be asking.
mx-3_4evr has a good write up on on clubprotege for putting together this custom setup and there is plenty of good general "custom itb tuning" info all over the internet.
If you are someone with an excellent understanding of how tuning and EMS work and have the time and fabrication skills required to finish the setup than please feel free to make an offer.
Thanks, Jeff
Last edited:
