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kenewagner
02-12-2007, 02:12 PM
Will a stock fuel rail provide enough flow for 60lb injectors? At what point on a high performace engine does the fuel rail and regulator need to be upgraded. Everyone knows the fuel pump needs upgrading along the way, but with current SCs climbing in HP numbers and better blowers becoming available when does the rest of the system need attention:confused:

Ken

91supacoop
02-12-2007, 02:50 PM
i am using 75# injectors and the stock fuel rails 502HP and 508ft lbs on an engine dyno with 1.7L AR

kenewagner
02-12-2007, 03:19 PM
i am using 75# injectors and the stock fuel rails 502HP and 508ft lbs on an engine dyno with 1.7L AR

On a 3.8 SC motor? Thats impressive. Are you using the stock regulator as well??

Ken

91supacoop
02-12-2007, 03:27 PM
Thanks:D I can't wait to actually put it in a car. Yes those numbers are on a 3.8SC motor.
Yours is definitly looking pretty impressive as well. Can't wait to see the #'s it puts down. Your work is absolutely stunning.

Here is a thread: (pics on page 9)
http://www.sccoa.com/forums/showthread.php?t=78852&highlight=CMRE+1.7L

And no i am not using the stock FPR. I am using the adjustable FPR from SCP. Picture 3 is a good shot of the regulator and what of the rail you can actually see

I was acutally told they stepped it up to 92# injectors, but as it turns out it looks like they were just buying themselves some time(they were way behind on the motor* and running out of excuses):rolleyes: when i got the printout of my tune it was tuned on 75#ers.

* in their defense....I did tell them to take their time

kenewagner
02-12-2007, 08:27 PM
Thanks:D I can't wait to actually put it in a car. Yes those numbers are on a 3.8SC motor.
Yours is definitly looking pretty impressive as well. Can't wait to see the #'s it puts down. Your work is absolutely stunning.

Here is a thread: (pics on page 9)
http://www.sccoa.com/forums/showthread.php?t=78852&highlight=CMRE+1.7L

And no i am not using the stock FPR. I am using the adjustable FPR from SCP. Picture 3 is a good shot of the regulator and what of the rail you can actually see

I was acutally told they stepped it up to 92# injectors, but as it turns out it looks like they were just buying themselves some time(they were way behind on the motor* and running out of excuses):rolleyes: when i got the printout of my tune it was tuned on 75#ers.

* in their defense....I did tell them to take their time

Awesome engine and numbers, bet you proud of that. Love the way the sc is going to new heights with diffrent paths to more HP. I hope to dyno soon but the weather is killing us off. 4 to 6 inches of snow predicted tonight.

Ken

Mike8675309
02-12-2007, 09:09 PM
No one has found that the fuel rails can't support it. But to be honest, I'm not willing to see how far they can go. Getting some better fuel rails made for my 60's.

kenewagner
02-12-2007, 11:21 PM
No one has found that the fuel rails can't support it. But to be honest, I'm not willing to see how far they can go. Getting some better fuel rails made for my 60's.


Can you enlighten us to what changes you plan? A billited fuel rail maybe?

Ken

kenewagner
02-13-2007, 08:52 AM
i am using 75# injectors and the stock fuel rails 502HP and 508ft lbs on an engine dyno with 1.7L AR

Was the fuel rail modified in any way to fit the AR? With a M112 the fuel rail needs to be longer

Ken

XR7 Dave
02-13-2007, 09:29 AM
Was the fuel rail modified in any way to fit the AR? With a M112 the fuel rail needs to be longer

Ken

Yes, most likely the exact same modifications as what you had to do.

kenewagner
02-13-2007, 10:16 AM
Yes, most likely the exact same modifications as what you had to do.

If you had to guess Dave, at what point does the stock fuel rail and regulator peak at. Did you run 400+ RWHP with a stock fuel rail?A lot of people are exceeding the old standards of HP for the 3.8 with the new blower options and heads and manifolds yet to come:) . I dont see a lot of attention to the fuel system upgrades with the exception that everyone always know to up grade the fuel pumps. I have not seen much dialog on this question unless its a David Neibert or another owner at the top of the HP list.

Ken

Mike8675309
02-13-2007, 08:46 PM
Someone is still making them for me. I was spurred onto the thought as I pondered my fuel system upgrade, but then when the AR became available to order that finalized it. They'll look something like the ones attached. The design is similar to what you've seen on other AR cars.

Everything I've seen has led me to believe that as long as you stay under 400rwhp the stock rails are more than sufficient. Since there hasn't been a good way to monitor this I'm not sure we'll ever know for sure. I was hoping to have time to put my motor on an engine dyno and swap out various using an exhaust manifold with an oxygen sensor for each tube. But I'm not going to have time (or money) to play with that idea this year. I feel that's the only way to know for sure, take a powerful motor and monitor the a/f ratio out of each cylinder on a dyno.