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TPI fuel pressure regulator

PostPosted: November 25th, 2008, 3:19 pm
by grumpyvette
I was asked if adding an adjustable fuel pressure regulator helps, on those TPI engines...

naturally the results depend on your application and combo, as an example on the 1985-1996 corvette I useually work on...your engine power is regulated to a large extent by the rate at which you can EFFECTIVELY BURN fuel/air mixture

the adjustable fuel pressure regulators can in some combos help noticably IF the injectors used are running at the ragged upper edge of thier flow limits, but in most cases they do very little, WHY?? well the cpu controls the injectors pulse width effectively controlling your air/fuel ratios from feed back from the O2 sensors in the exhaust, at least in theory the injectors are large enought to supply 100% of your engines potential needs running less than 80% pulse width. at the 37psi-42psi the stock regulator provides. BUT if youve made significant changes to the engine combo youll need to EITHER increase the injector size OR cheat by upping the supply pressure to those smaller injectors, obviously adding more pressure with a regulator is limited to the maximum the fuel pump can supply and in most case the stock pump maxs out just under 48psi

play with this

youll soon find that useing larger injectors and letting the CPU REDUCE the pulse width is far more effective that trying to boost flow on stock injectors

Matching the Injector to the Engine: generic calculation

Injector Flow Rate (lb/hr) = Engine HP x BSFC
Number of Injectors x 0.8

Injector Size
14 lb./hr.......up to 225
19 lb./hr.....225-300
24 lb./hr.....300-385
30 lb./hr......385-480
36 lb./hr......480-575
42 lb./hr.......575-670
50 lb./hr ......670-800
Horsepower Range ... 0036-1.pdf

BTW there ARE REPAIR KITS available ... ao=0#rstop
retired engineer ,engine builder, 1985/92/96 vettes(all modifyied)