Sunday, October 11, 2009

Diff mount & fuel lines

I know its been a while since the last update but there has not been really anything new to report.
I fixed my issue with the rear differential mounting bracket. I cut the rear support gussets, mounted the differential to the bracket after some slight persuasion to the bracket, and brought the entire assembly to the welder and had it welded in place. Painted it, done.






Fuel system:
Next up was the upgrade of the fuel lines and pump. The stock Miata fuel pump and lines are not adequate for the bigger V8 engine so both need to be replaced. For the fuel pump this means removing the in tank assembly, thankfully Mazda provides an access panel on the rear package tray so the tank does not need to be removed to replace the pump. Simply remove the access panel, then carefully remove the fuel pump assembly unit. The stock fuel pump can then be removed. I am replacing the stock fuel pump with a Walbro 225 which will be able to supply the new engine with enough fuel. Since I am installing larger 3/8 fuel line versus the factory 5/8 line, I needed to have a way to connect the new lines to the fuel pump assembly at the tank. There are several ways this could be done but I drilled out the 5/8 hard lines and replaced them with -6 (3/8) AN bulk head fittings which will connect to -6 braided hose to a Corvette fuel filter/regulator then 3/8 hard line to the engine bay.

Here are some pictures of the process so far:

Top of gas tank with the stock fittings.


Stock fittings removed:



New pump and fittings mounted:



Assembly installed with -6 braided supply and return hoses connected:



Here is the Corvette fuel filter/regulator installed under the car (the other 2 lines are the rear brake and fuel tank vent lines) :



Next on the to do list is to run the 3/8 fuel line from the filter to the front of the car. Then I can install the rear subframe back into the car. I wanted to finish the fuel setup first before installing the rear subrame, one less thing that could be in the way.