So whose using a rising-rate fuel pump regulator?, Not turbos; or using a cold start valve as a 5th injector? Options

[computers4kids]

Who has played with a rising-rate regulator or adding a switch to a cold start valve to be used as a 5th injector to get a little extra pony power?
Here's one...
MicroDynamics RisingRate Regulators are designed for use with all types of fuel injection systems. Added to standard systems they increase the mixture range for high performance or provide "boost or load enrichment" on both turbo and naturally aspirated engines. Rising-Rate will also give more fuel at the top end without going over-rich lower down the rev/power range.

A MicroDynamics RisingRate Regulator is often the only form of fuel enrichment required for many retrofit turbo conversions and is usually the easiest way to obtain increased fuelling on production injected race vehicles.

Here's one by Bell Engineering $179

Here is an interesting article how to make your own rising-rate pressure regulator from a stock 914 regulator

[computers4kids]

Didnt the 1.8s have a manifold referenced fuel pressure regulator? Most modern cars have a manifold referenced regulator. It is a bit amazing that the d-jet cars didnt have one. Since the d-jet cars didnt have one, adding one would probably make it run worse, since they have already compensated for the differences in flow between open and closed throttle.

Z,

Are you running cards or FI? djet & an extra Ljet laying around...which really sounds interesting.

Cause if you are running a carb (or carbs)

Unless you have a blow through setup.

I don't see how a rising rate fuel regulator will help you. Setting the regulator to start increasing fuel pressure in the higher rpms should result in more fuel being pushed through the injectors. Lower rpms, fuel stays closer to stock pressure, 29. ECU can be left alone--idle mixture OK. MPS perhaps?

I can see a 5th injector helping you... if you need one.

Conversely, if you have a draw through carb. A rising rate won't really help you. As the carb never see the boost signal.

And have you dyno'd that engine yet???? Unfortuately not...would be interesting to play with this idea on a dyno.
I have some more mindless questions coming later.... (IMG:style_emoticons/default/drooley.gif)

C