Adjustable fuel pressure regulator good or bad
03-26-2015, 02:00 PM
#1
Adjustable fuel pressure regulator good or bad
On my 383 build I am considering installing a adjustable fuel pressure regulator. Also the injectors will be 36lb with a 255lph fuel pump. My concern is will the stock rated fuel pressure regulator be at its max with this setup. In the past I seen some people discourage the use of a adjustable regulator because it can screw with the computer. BTW the engine is a 93 lt1. Please educate me lol. The engine is bored and stroked, stock head work with 1.6 rockers, 230/236 cam, 52mm Tb, ported intake and etc.
03-26-2015, 02:22 PM
#2
Le Mans Master
On my 383 build I am considering installing a adjustable fuel pressure regulator. Also the injectors will be 36lb with a 255lph fuel pump. My concern is will the stock rated fuel pressure regulator be at its max with this setup. In the past I seen some people discourage the use of a adjustable regulator because it can screw with the computer. BTW the engine is a 93 lt1. Please educate me lol. The engine is bored and stroked, stock head work with 1.6 rockers, 230/236 cam, 52mm Tb, ported intake and etc.
Last edited by WW7; 03-26-2015 at 02:28 PM.
03-26-2015, 05:07 PM
#3
Who told you 36 lb injectors were what you needed??? You should get the adjustable regulator when you start modifying the engine ,you may need to make adjustments to get it running perfect...When I got my 383 , that and a bigger fuel pump were the first things my tuner had me replace..The person doing the tuning should be asked these same questions,they should know what works best... WW
03-26-2015, 05:25 PM
#4
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It won't hurt you to get one for tweaking after your tune is finished, no.
I would double and triple check the injector sizing, and run it by whomever plans to do your tuning, but 36 sounds about right, maybe on the big side, for that combination to me.
I would double and triple check the injector sizing, and run it by whomever plans to do your tuning, but 36 sounds about right, maybe on the big side, for that combination to me.
03-26-2015, 06:27 PM
#5
No problem. I have both sets of injectors.
03-27-2015, 01:31 AM
#6
Race Director
03-27-2015, 05:16 AM
#7
Le Mans Master
Thats why I mentioned the injector size in my post..Im running a 383 with around 400 hp and Im using 24 lb injectors..The only guys I know using 36 lb injectors are heavily modified with big heads, running big intakes like superrams and big cams..I called Jon at fuel injector connection and told him how much power I would be making, he told me which size injectors I would need...WW
Last edited by WW7; 03-27-2015 at 05:22 AM.
03-27-2015, 08:57 AM
#9
Race Director
This is the same question I have. Go with the original regulator or go with adjustable? I have a 383 with the Hot Cam and a 52 mm TB and 1.6 rockers coupled with 32 lb injectors.
03-27-2015, 06:18 PM
#11
Melting Slicks
the standard regulator is fine if you have the standard setup and injectors,
if you have changed and modified the injection (different size injectors, pump etc) then spend the extra $100 - $200 to fit an adjustable regulator.
fuel pressure is extremely important for everything from idle to wide open throttle, so make sure you can set it exactly where it should be
if you have changed and modified the injection (different size injectors, pump etc) then spend the extra $100 - $200 to fit an adjustable regulator.
fuel pressure is extremely important for everything from idle to wide open throttle, so make sure you can set it exactly where it should be
03-27-2015, 11:52 PM
#12
Race Director
...And how do you know "exactly where it should be"?
When the ECM is in closed loop mode it will adjust the injector pulse width to get the AFR it is looking for. The fuel pressure is not a factor.
Fuel pressure affects the injector flow rate. It affects how the engine runs in open loop mode only. That would be when the engine is cold and at WOT.
When the ECM is in closed loop mode it will adjust the injector pulse width to get the AFR it is looking for. The fuel pressure is not a factor.
Fuel pressure affects the injector flow rate. It affects how the engine runs in open loop mode only. That would be when the engine is cold and at WOT.
03-28-2015, 04:19 AM
#13
Melting Slicks
...And how do you know "exactly where it should be"?
When the ECM is in closed loop mode it will adjust the injector pulse width to get the AFR it is looking for. The fuel pressure is not a factor.
Fuel pressure affects the injector flow rate. It affects how the engine runs in open loop mode only. That would be when the engine is cold and at WOT.
When the ECM is in closed loop mode it will adjust the injector pulse width to get the AFR it is looking for. The fuel pressure is not a factor.
Fuel pressure affects the injector flow rate. It affects how the engine runs in open loop mode only. That would be when the engine is cold and at WOT.
fuel pressure is very important in an efi engine, so therefore you need a starting point, usually 43 psi.
we are talking about modified systems in modified engines, the discussion is, is an adjustable fuel pressure regulator good or bad ?
I would guarantee that most people here with modified engines and efi (particularly if they track their car) will have adjustable regulators, and know exactly where their fuel pressure is set. I doubt if you asked some of these guys, what do you set your fuel pressure at for street and track, their answer would be, gee I dont know it doesnt really matter coz the computer adjusts it anyway !
"exactly where it should be" is where you set it for your preferred setup, and if it alters then you will know that a problem is developing somewhere and your performance wont be as good as it could be.