Adjustable fuel pressure regulator
Discussion
Hi, I was reading in the Steve Heath bible yesterday that the simple fitting of an adjustable fuel regulator, and an associated increased pressure, can give an extra 12 bhp to a standard engine. Two questions - has anyone tried a before and after rolling road session to prove that this is indeed the case and if so then is there a particular regulator that anyone would recommend? I'm also assuming that if the pressure is increased then the risk of an old hose bursting will also increase? Thanks.
Hi mate...Im not sure that its as clear cut as that...I have an adjustable FPR as i have a sneaky suspicion that my engine may be a 3.9 range rover..Its pushing 180bhp at the flywheel and 212lbsft of torque..Which suggested either a really healthy 3.5 or TVR slipping a 3.9 in there as they might of not had a 3.5 spare at the time..It wouldn't surprise me, There is no history of cam work and the mileage is pushing 75,000 on a 26 year old car.
Tower view racing did a fair bit of work on it when it was owned by a previous owner but there is no record of head or cam work.
When i bought the car it already had a malpassi AFPR on it but was seeping a small amount of fuel from the diaphragm, I had a solid state type fitted which was 2.5bar, However it seemed to lack power and the plugs suggested it was running lean..
I have a feeling that after fitting the new AFPR that it may of finished off the fuel pump as this can happen if the fuel pressure is set too high.
There can be issues with injectors also..
http://www.google.co.uk/url?sa=t&rct=j&q=&...
I have raised mine to 2.7bar which seems to be about right as the plugs indicated normal running now and she pulls like a train.
Just raising the fuel pressure can actually have a negative effect, Especially if your engine doesn't need it!...I think people who have fitted bigger injectors with a different ECU fuel maps with MS systems see a greater and a more reliable change..
Although i could be talking twaddle.....
Tower view racing did a fair bit of work on it when it was owned by a previous owner but there is no record of head or cam work.
When i bought the car it already had a malpassi AFPR on it but was seeping a small amount of fuel from the diaphragm, I had a solid state type fitted which was 2.5bar, However it seemed to lack power and the plugs suggested it was running lean..
I have a feeling that after fitting the new AFPR that it may of finished off the fuel pump as this can happen if the fuel pressure is set too high.
There can be issues with injectors also..
http://www.google.co.uk/url?sa=t&rct=j&q=&...
I have raised mine to 2.7bar which seems to be about right as the plugs indicated normal running now and she pulls like a train.
Just raising the fuel pressure can actually have a negative effect, Especially if your engine doesn't need it!...I think people who have fitted bigger injectors with a different ECU fuel maps with MS systems see a greater and a more reliable change..
Although i could be talking twaddle.....
I have had good results from a "Rising Rate" regulator but you must be careful as the fuel pressure in the rail will increase above the idle setting. This stresses all the little hoses which can burst if weakened. And usually you will only notice this when under full throttle caning along with a hot engine bay and the ignition going at full chat....
I think the main thing about the rolling road is NOT to worry too much about power figures unless you have had an engine build, Im going to speak with them to ask if they can do an AFR test first and not just power runs...These cars are over 20 years old and just need to be tested to make sure they are running right...Not thrashed to squeeze the last drop of power out of them for the sake of an award or a bit of paper...Ziga
Realistically, if you want a faster car, just buy one. By the time you fanny around trying to overcome the limitations of a 50+ year old 2-valve-per-cylinder engine design with the reciprocating mass of Newcomen's beam engine you may as well save your money and buy something Japanese, light and revvy.
Just getting the RV8 to meet its quoted power/torque should be considered achievement enough
Just getting the RV8 to meet its quoted power/torque should be considered achievement enough
wooly350i said:
I've got a nearly new rising rate fpr going begging if any one is interested, only thing I've not got is the fuel rail adaptor which seem to available separately from various sources.
Hi I may well be interested. Can you drop me an email and let me know how much you're looking for. Thanks.Gassing Station | Wedges | Top of Page | What's New | My Stuff