aftermarket fuel pressure
04-13-05, 05:38 AM
#1
aftermarket fuel pressure
ok ive done the parralel fuel setup. but ive got a question my fpr will only seem to do two setting that are close to the stock 35 psi. either it will do 32psi will idel and cruising, then floor it and it will go to 38 psi. the other one close to it is 38 psi idel and cruising, 44 psi when i floor. the old butt dyno cant really tell a different and on the a/f gauge i saw only one bar difference between the two. i plan to run nitrous sooner or later which setup would be better right now and then i can switch to the other when i start running the juice. 32-38 or 38-44.
04-14-05, 06:12 AM
#2
Jesus is the Messiah
Unless you have a wideband, I wouldnt trust your AF gauge to tell you the difference between different fuel setups (unless somethings going really wrong)
What FPR are you using?
What FPR are you using?
04-15-05, 08:10 AM
#6
Senior Member
iTrader: (2)
Join Date: Oct 2003
Location: Pensacola, FL
Posts: 327
Likes: 0
Received 0 Likes
on
0 Posts
That depends on how much fuel your motor needs. The reason the FP changes when you floor it is engine vacuum is removed from the FPR diaphram. You should set the fuel pressure with the vacuume line OFF of the FPR.
On a second note, why did you bother with a modded fuel system on an NA?
On a second note, why did you bother with a modded fuel system on an NA?
Trending Topics
04-15-05, 08:17 AM
#8
Senior Member
iTrader: (2)
Join Date: Oct 2003
Location: Pensacola, FL
Posts: 327
Likes: 0
Received 0 Likes
on
0 Posts
My question remains the same. Unless he plans on spraying more then 125 - 150hp and then the question remains how far back he upgreaded his lines...
Last edited by LT8TurboII; 04-15-05 at 08:37 AM.
04-15-05, 08:29 AM
#9
Jesus is the Messiah
Originally Posted by projectredsuns
which is better running n/a 32-38psi or 38-44psi, and which is better when running nitrous.
Obviously you want more fuel when running nitrous, but make sure your fuel pump can keep up with it.
It also depends on how much you are spraying, as mentioned before.
If I were you, I'd run a true wet kit instead of just upping the fuel pressure.
04-15-05, 05:59 PM
#10
i will be running a true wet kit, nx kit plus the genx2 upgrade, for ignition control crane cam hi-6 plus retard. my fuel setup is exactly like on fc3spro.com http://fc3spro.com/TECH/MODS/FUEL/pararail.jpg. fuel pump is a walbro.
and thanks for finally giving some advice i was starting to get scared
and thanks for finally giving some advice i was starting to get scared
04-18-05, 08:02 AM
#13
Jesus is the Messiah
Are you only retarding the ignition on the leading coil with the crane unit?
Because if you do that. . . you'll end up with negitive timing split, and likely need a new engine, as the leading/trailing split under high load is zero degrees stock.
Because if you do that. . . you'll end up with negitive timing split, and likely need a new engine, as the leading/trailing split under high load is zero degrees stock.
04-18-05, 03:53 PM
#14
i was going to follow the write up on fc3s.org on the install http://www.fc3s.org/how_tos/electrical/hi_6.html would i be able to use the same unit and just run the wires to the trailing coil as well. and to wire the retard i was going to follow page 23 of this http://static.summitracing.com/globa...00%282%291.pdf
04-19-05, 10:28 PM
#15
I wish I was driving!
Either fuel pressures would be fine, as long as you tune your engine for it with something like an S-AFC.
You tune the fuelling of your nitrous with your nitrous jet... it doesn't care if you have 5 psi or 500 psi of fuel pressure, as long as you;ve got the correct jet installed.
That being said, the stock manifolds, injector angles, and injector positions were designed for ~39 psi of fuel pressure with no vacuum reference, so it best to keep aftermarket fuel pressure to about the there.
Also, 3 degrees of retard with a stock ECU and stock timing is a waste. Don;t bother.
Also, you cannot simply retard the leading ignition with the Hi-6 you'll blow your engine with the negative split. You would need to retard both of the trailings with two separate retard units as well, and this can get expensive.
You tune the fuelling of your nitrous with your nitrous jet... it doesn't care if you have 5 psi or 500 psi of fuel pressure, as long as you;ve got the correct jet installed.
That being said, the stock manifolds, injector angles, and injector positions were designed for ~39 psi of fuel pressure with no vacuum reference, so it best to keep aftermarket fuel pressure to about the there.
Also, 3 degrees of retard with a stock ECU and stock timing is a waste. Don;t bother.
Also, you cannot simply retard the leading ignition with the Hi-6 you'll blow your engine with the negative split. You would need to retard both of the trailings with two separate retard units as well, and this can get expensive.
04-20-05, 07:08 AM
#17
BOOSTED Vert
Join Date: Sep 2002
Location: Miami
Posts: 2,307
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by projectredsuns
so basically i wasted my money on hi-6 with a retard control. would i have to go standalone to control both coils? should i still install the hi-6 and sell the retard part of it? is the hi-6 safe to use it with nitrous?
no just buy 2 more units.... I had a 75 shot on stock fuel system.. Took it just fine.
04-20-05, 07:38 AM
#18
Originally Posted by MARTIN
no just buy 2 more units.... I had a 75 shot on stock fuel system.. Took it just fine.
04-20-05, 09:32 AM
#19
BOOSTED Vert
Join Date: Sep 2002
Location: Miami
Posts: 2,307
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by projectredsuns
so two more hi-6 plus 2 more retard units? or just two more hi-6? im starting with 75 and working my way thats why im buying this stuff now. i remember readng on 1300cc.com that 75 with stock retard is fine.
04-20-05, 10:43 AM
#21
Senior Member
iTrader: (2)
Join Date: Oct 2003
Location: Pensacola, FL
Posts: 327
Likes: 0
Received 0 Likes
on
0 Posts
How much are the Hi-6 boxes with the retard control?
You might be able to get you a Microtech and use the output to pull timing when on the jug for the same price.
Also from what I understand of rotaries and alot of spray you will want the motor ported anyway.
You might be able to get you a Microtech and use the output to pull timing when on the jug for the same price.
Also from what I understand of rotaries and alot of spray you will want the motor ported anyway.
04-20-05, 06:58 PM
#25
I wish I was driving!
Originally Posted by Digi7ech
Isn't 40-45psi stock pressure?
I wouldn't run less than stock since that would mean less atomization and worse fuel properties.
Right now I run 50 psi under vacuum ob my Aeromotive FPR(it's this ****!)
I wouldn't run less than stock since that would mean less atomization and worse fuel properties.
Right now I run 50 psi under vacuum ob my Aeromotive FPR(it's this ****!)
50 psi under vacuum is silly fuel pressure, especially if you're using stock intake manifolds, and even worse, the stock ECU. That's 20 psi more than the stock FPR runs! All that does is makes the fuel spray out of the injector at a higher velocity, and wet the intake runners. This kind of fuel pressure would actually increase the chances of nitrous backfire since it will be spraying more fuel directly onto the intake runner walls.
Given your mod list, I am surprised your car runs at all, given how rich it must be from stock injector maps and no fuel controller.