951 fuel system
05-28-2005, 02:12 PM
#1
Banned
Thread Starter
Join Date: May 2005
Posts: 17
Likes: 0
Received 0 Likes
on
0 Posts
951 fuel system
I've increased from 2.5l to 2.7l and am now starving for fuel so have had to limit the turbo pressure with a manually adjustable controler. I was hoping the larger 3.0 FPR would solve a portion of this, but am looking for larger injectors should I have to go that far. Any insights would be greatly apreciated.
Currently it is running ok, but I can't really see what the engine can do until I get more fuel. If anyone can supply Injector # rates and Fuel Pressure they ended up at as compared to thier 951 displacement and turbo pressure, then I could at least interpolate a starting point for my injector/FPR setup.
In the mean time, I'll install the 3.0 FPR unit when it gets here and see what I see with the stock injectors.
Many Thanks,
llf264
Currently it is running ok, but I can't really see what the engine can do until I get more fuel. If anyone can supply Injector # rates and Fuel Pressure they ended up at as compared to thier 951 displacement and turbo pressure, then I could at least interpolate a starting point for my injector/FPR setup.
In the mean time, I'll install the 3.0 FPR unit when it gets here and see what I see with the stock injectors.
Many Thanks,
llf264
05-29-2005, 10:45 AM
#2
Burning Brakes
Most 2.5l users with the typical mods and "big" turbos are running anywhere from 55lb to 83lb injectors. I don't think I've ever seen a published number for the stock injectors but have read that some folks here have used test bench data do determine that they are in low to mid 30lb range.
What are you using for engine management?
What are you using for engine management?
05-29-2005, 01:21 PM
#3
Banned
Thread Starter
Join Date: May 2005
Posts: 17
Likes: 0
Received 0 Likes
on
0 Posts
Combination
I'm using the stock system for now as I've seen some people be able to put it to good use with more power than mine. I'm sure it would be easier with an aftermarket, but for now I'm simply limited to what I've got in that department.
One observation I've been able to make over a lifetime of working on cars is that you can often do a lot more with less fuel if you take the time to make it work. And on the time vs. money thing, I've got a lot more time on my hands these days.
I'm trying to locate data on the 968 3.0l turbo injectors as I believe with the restrictor plate and a fuel pressure between 2.7-3.0bar, the factory would have used the smallest injectors possible and that would give me an upper range limit for my application.
If anyone has anything for sale I'd always be interested to see what they have, but when it comes to MAF or other parts, I've always been able to use Ford, BMW and VW jukyard parts to put together some realy trick stuff for a fraction of the cost.
One observation I've been able to make over a lifetime of working on cars is that you can often do a lot more with less fuel if you take the time to make it work. And on the time vs. money thing, I've got a lot more time on my hands these days.
I'm trying to locate data on the 968 3.0l turbo injectors as I believe with the restrictor plate and a fuel pressure between 2.7-3.0bar, the factory would have used the smallest injectors possible and that would give me an upper range limit for my application.
If anyone has anything for sale I'd always be interested to see what they have, but when it comes to MAF or other parts, I've always been able to use Ford, BMW and VW jukyard parts to put together some realy trick stuff for a fraction of the cost.
07-01-2005, 02:53 PM
#4
Addict
Rennlist Member
Rennlist
Site Sponsor
Rennlist Member
Rennlist
Site Sponsor
The 968T used a 3.8bar FPR. Increasing the injectors size and/or running higher fuel pressure will give you fuel across the RPM range, however your AFR will be all over the board. Unless you have a way to control/tune your AFR you are facing a losing battle.
The Motronic system is fine, look at the 951 forum where a 2.5l made 472rwhp on a Mustang dyno. That was with the stock Motronic, custom chip/MAF and a PiggyBack.
Injectors or fuel pressure regulator are the least expensive parts. Tuning is what will cost!
The stock injectors running 3.8+ bar fuel pressure are ok for about 300-330rwhp, but they will be maxed out. Might be ok for bursts on the street, but a risk on the track.
The Motronic system is fine, look at the 951 forum where a 2.5l made 472rwhp on a Mustang dyno. That was with the stock Motronic, custom chip/MAF and a PiggyBack.
Injectors or fuel pressure regulator are the least expensive parts. Tuning is what will cost!
The stock injectors running 3.8+ bar fuel pressure are ok for about 300-330rwhp, but they will be maxed out. Might be ok for bursts on the street, but a risk on the track.