Injectors -
The ECU should be able to handle a 15% leeway in flow rate, but I'm afraid to go any further if I want good low rpm performance.... too large can result in a rich idle and low rpm running - and lowering the fuel pressure to compensate may result in a poorly atomized mixture - so 15% larger is where I decided to peg it on size increase and keep it close to the stock rail pressure as a base setting. The stock injectors are B210H - rated at 210cc/min.... after a bit of research and a failed attempt to fit Honda injectors, I found some B240H injectors - same impedence as the original injectors, but 15% higher flow rate (240cc/min) and identical dimensions. They were used on a Canadian vehicle, but I don't know which one for sure.
The only way to get these new injectors to flow enough fuel under WOT with 6-8psi boost is to jack up the fuel pressure..... to about 55psi. I could use the stock injectors if the fuel pressure could go higher (70psi+), but I have no idea what the OE fuel pump can handle. I did note that the Bosch replacement pumps are rated at 70psi and plenty of flow for 200HP or so - but as pressure goes up, flow decreases - and I don't know if the rated flow is at stock rail pressure or at the 70psi rating. So, I'll play it in the middle ground of the largest injector I think the ECU can handle and hope the fuel pump can do the job at 55psi..... I think it probably can.
To increase fuel pressure under boost, one of Corky Bell's newest whizzbang Multi-Role Regulators (remember, the OE regulator went bye-bye with the grinder) will be tried:
![[Linked Image]](http://i77.imagethrust.com/t/338378/img3118.jpg)
The lower (smaller) cylinder contains the 1:1 regulator for normal no-boost - and functions (hopefully) exactly as the OE regulator to counter the change in pressure in the intake runners as manifold vacuum drops. The upper hat section contains the rising rate mechanism that serves to restrict fuel return flow back to the tank when under boost - effectively increasing pressure in the fuel rail and causing the injectors to deliver fuel at a rising rate dependant upon boost pressure. Adjustments are visible in the two threaded shafts protruding from the top and bottom (one for base rail pressure, one for rate of gain under boost) - and a further needle adjustment for gain onset - tuning out the flat spot as the engine transitions into boost. The small fittings go to intake vacuum and discharge plenum boost ports.
The question was where and how to mount it - there's no room on the firewall (preferred location). Also, Corky hasn't figured out a mounting bracket yet - the brackets supplied as a suggestion were not acceptable to me at all. I didn't like the idea of mounting it in a crush zone, but found no perfect place available where all of the adjustments could be in easy reach for tuning, so I decided to mount it in the area behind the passenger headlight previously occupied by the air filter housing, using the mounting holes already there:
![[Linked Image]](http://i77.imagethrust.com/t/338377/img3115.jpg)
Made another wooden bracket mockup:
![[Linked Image]](http://i77.imagethrust.com/t/338381/img3122.jpg)
This funky looking bracket was made to provide a 3-point mount:
![[Linked Image]](http://i77.imagethrust.com/t/338380/img3121.jpg)
and bolted onto the inner fender:
![[Linked Image]](http://i77.imagethrust.com/t/338382/img3123.jpg)
to provide a solid mount for the regulator - now complete with fuel fittings, pressure gauge and sender for the cab gauge:
![[Linked Image]](http://i77.imagethrust.com/t/338383/img3136.jpg)
So, a little more is done while waiting for the injectors to come back from CruisinPerformance and the blower to be shipped. Doing a little at a time when I feel like it is sure better to me than trying to do everything on a schedule. <img src="/forums/images/graemlins/kewl.gif" alt="" />
Checklist remainder:
1) make the nose drive brace/idler bracket
2) fashion a 2 piece air duct with an aluminum sleeve (in the middle) to receive the CCV hose
3) shorten the throttle and kickdown cables
4) lengthen the TPS/IAC harness
5) make paper gaskets for the blower, blower plate and inlet flange
6) make an EGR block-off plate
7) drill/tap a mounting hole for the choke and capacitor that are normally mounted on the coil bracket
8) put everything together one last time
9) make a hood scoop
10)tune it
Frank