944 Turbo Larger Injectors? +Oil Leak
12-27-2001, 01:07 AM
#1
Addict
Rennlist Member
Rennlist Member
Thread Starter
944 Turbo Larger Injectors? +Oil Leak
Still trying to figure out where my oil leak is coming from, more on that later but first:
I'm looking into larger injectors so I can push the car a bit without using a FPR (at least initially). A friend of mine suggested that injectors from a BMW could work well, what's the flow rate for stock injectors? What other aftermarket injectors should I look into?
Anyway, intake manifold is off, turbo oil supply line is dry, and all hoses associated to the oil cooler are also fine. The passanger side of the engine looks relatively clean, but mid to lower driver's side is completely soaked in oil, shortly after pressure washing. Any recommendations on what to check? The car's not loosing antifreeze, or powersteering fluid, but if driven hard up to 1 quart of oil per 100 miles leaks out. There was oil in the air box, so I think it's being sprayed while driving (shoots oil over the driver's fender/hood, and even left headlight cover at high speeds when on boost). The upper side of the turbo is dry also. I'm going to try and clean it up tonight (I need to start driving the car regardless of if I find the problem or not), and try to locate it again. Although the oil pan gasket, and the front main seal, and even the balance shaft housing seals are possible, I'm still guessing it's a turbo oil return line, is this common? Where should I check? Ideas?
Thanks,
Ahmet
I'm looking into larger injectors so I can push the car a bit without using a FPR (at least initially). A friend of mine suggested that injectors from a BMW could work well, what's the flow rate for stock injectors? What other aftermarket injectors should I look into?
Anyway, intake manifold is off, turbo oil supply line is dry, and all hoses associated to the oil cooler are also fine. The passanger side of the engine looks relatively clean, but mid to lower driver's side is completely soaked in oil, shortly after pressure washing. Any recommendations on what to check? The car's not loosing antifreeze, or powersteering fluid, but if driven hard up to 1 quart of oil per 100 miles leaks out. There was oil in the air box, so I think it's being sprayed while driving (shoots oil over the driver's fender/hood, and even left headlight cover at high speeds when on boost). The upper side of the turbo is dry also. I'm going to try and clean it up tonight (I need to start driving the car regardless of if I find the problem or not), and try to locate it again. Although the oil pan gasket, and the front main seal, and even the balance shaft housing seals are possible, I'm still guessing it's a turbo oil return line, is this common? Where should I check? Ideas?
Thanks,
Ahmet
12-27-2001, 05:05 AM
#2
Race Director
Uh, don't even bother with injectors, you'll end up making thing worse with no improvements. First learn the difference between saturated vs. peak&hold injectors and low vs. high-impedance.
Then figure out that more power comes from moving more air through the engine, not dumping more fuel into it. The stock injectors flow-rates are 37lbs@2.5bar or 43lbs@3bar. This is good for 350-375hp, so you are nowhere near maxxing them out (the ONLY reason to replace them).
Check out the rear cam-housing cap and its gasket for the mystery leaks.
Then figure out that more power comes from moving more air through the engine, not dumping more fuel into it. The stock injectors flow-rates are 37lbs@2.5bar or 43lbs@3bar. This is good for 350-375hp, so you are nowhere near maxxing them out (the ONLY reason to replace them).
Check out the rear cam-housing cap and its gasket for the mystery leaks.
12-27-2001, 05:54 AM
#3
Addict
Rennlist Member
Rennlist Member
Thread Starter
Danno, thanks for the response.
Where do you think I can look for more info on injectors? I'm planning to modify this car, but probably not past 350hp anytime soon, so sticking with stock injectors can make sense for me. Anyway, I've heard that a higher flowing injector can perform better at a lower duty cycle, rather than pushing one that's nearing it's limit, at a higher fuel pressure. Do you know what the stock fuel pressure is supposed to be btw?
For the oil leak, I will check the rear cam housing cap, and it's cork gasket but I don't think that's the source of my leak(s). Oil seems to be concentrated on the driver's side of the engine. I need to start driving this car, so I think I'm going to put it back together, and pressure wash the engine comp. see if that helps.
Ahh, so much to fix... With the help of the board though, it should go a bit smoother.
Thanks again for the response,
Ahmet
Where do you think I can look for more info on injectors? I'm planning to modify this car, but probably not past 350hp anytime soon, so sticking with stock injectors can make sense for me. Anyway, I've heard that a higher flowing injector can perform better at a lower duty cycle, rather than pushing one that's nearing it's limit, at a higher fuel pressure. Do you know what the stock fuel pressure is supposed to be btw?
For the oil leak, I will check the rear cam housing cap, and it's cork gasket but I don't think that's the source of my leak(s). Oil seems to be concentrated on the driver's side of the engine. I need to start driving this car, so I think I'm going to put it back together, and pressure wash the engine comp. see if that helps.
Ahh, so much to fix... With the help of the board though, it should go a bit smoother.
Thanks again for the response,
Ahmet
12-27-2001, 02:07 PM
#4
Advanced
Join Date: May 2001
Posts: 56
Likes: 0
Received 0 Likes
on
0 Posts
I got my 50 lb/hr injectors here http://www.injector.com/ for $300. They are the same ones huntley sells for $600. They also have 52 lb/hr bosch injectors for $400 a set. HTH.
Minh
Minh
12-27-2001, 06:45 PM
#5
Race Director
Anyway, I've heard that a higher flowing injector can perform better at a lower duty cycle, rather than pushing one that's nearing it's limit, at a higher fuel pressure.
To really make significant HP gains, you'll a new turbo and an aftermarket EFI system, like Rage2's install: http://forums.rennlist.com/scripts/r...&f=18&t=000341
At this point, larger fuel-injectors would make a difference for you.
Here's some links:
http://www.cruzinperformance.com/accel/page1-12.html
http://pro-flow.com/t-car.html
http://www.rceng.com/
http://www.supras.com/~riemer/sonict...rs/RCtech.html
http://www.sdsefi.com/index.html
http://www.shults.com/hypermail/w2wsave2/0299.html
http://www.autospeed.co.nz/C_article...4/article.html
http://www.autospeed.com/A_0102/article.html
http://www.wolfems.com.au/injector_flow_rates.htm
As for the oil leak, do you have oil on the bottom side of the hood? I had a nasty leak because my dipstick tube didn't have an O-ring where it goes into the engine.
12-28-2001, 02:42 AM
#6
Addict
Rennlist Member
Rennlist Member
Thread Starter
Minh Pho: That doesn't look to be a bad deal, thanks for the plug in. I'm going to do some research on injectors, will keep that supplier in mind when it's time to get some.
Danno, I appreciate the heads up on the dipstick tube. Mine was really loose, I've removed it along with the intake manifold, this could be it! That would make me a VERY happy man... Even if that wasn't my major leak, it's definately one of them, that would make perfect sense. I will check this tomorrow.
For the injectors, mine look to be a bit tired, I'm going to mod the 951 I thought I'd start by getting larger injectors before even turning up the boost. Before I go w/a larger turbo, I'm going to make a straight exaust from the turbo back, with one straight through resonator, turn up the boost (w/an APEX-i electronic boost controller) with enough fuel to match (w/an APEX-i air/fuel 'controller', and the larger injectors I'm planning to put in). I thought I'd get the injectors first, shortly followed by the APEX-i controllers, and an adjustible FPR. I'm going to keep the turbo in, as mine was rebuilt with a larger compressor housing as per previous owner. So that's going to stay until it doesn't make sense for me to keep it anymore, then might come a larger turbo and an MAF. I'm thinking this way what I put in could match the car's requirements in the future, or could be removed off this car to be swapped onto the next one if that's what it comes to. What do you think (there'll be a pause between the exaust +injectors +controllers, and the rest, need to sell my 944 NA first so I don't eat into my savings)? I've also browsed through your website (very nice btw, came upon it a long time ago, great articles about the limited slip diffs/torsen, etc. and the physics of racing articles). Anyway, I really appreciate all the info/links you've posted, I'll look at all of them when I get some time later this week.
Thanks again,
Ahmet
Danno, I appreciate the heads up on the dipstick tube. Mine was really loose, I've removed it along with the intake manifold, this could be it! That would make me a VERY happy man... Even if that wasn't my major leak, it's definately one of them, that would make perfect sense. I will check this tomorrow.
For the injectors, mine look to be a bit tired, I'm going to mod the 951 I thought I'd start by getting larger injectors before even turning up the boost. Before I go w/a larger turbo, I'm going to make a straight exaust from the turbo back, with one straight through resonator, turn up the boost (w/an APEX-i electronic boost controller) with enough fuel to match (w/an APEX-i air/fuel 'controller', and the larger injectors I'm planning to put in). I thought I'd get the injectors first, shortly followed by the APEX-i controllers, and an adjustible FPR. I'm going to keep the turbo in, as mine was rebuilt with a larger compressor housing as per previous owner. So that's going to stay until it doesn't make sense for me to keep it anymore, then might come a larger turbo and an MAF. I'm thinking this way what I put in could match the car's requirements in the future, or could be removed off this car to be swapped onto the next one if that's what it comes to. What do you think (there'll be a pause between the exaust +injectors +controllers, and the rest, need to sell my 944 NA first so I don't eat into my savings)? I've also browsed through your website (very nice btw, came upon it a long time ago, great articles about the limited slip diffs/torsen, etc. and the physics of racing articles). Anyway, I really appreciate all the info/links you've posted, I'll look at all of them when I get some time later this week.
Thanks again,
Ahmet
