Power AdderGetting a Supercharger or Turbocharger? Thinking about using Nitrous? All forced induction and N2O topics discussed here.
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We put 10 magnets on the left front wheel hub and a hall-effect switch to detect them. We recorded the pulses to a WAV-file using the microphone input on a laptop.
I analysed the WAV-file using mu own software and these are the numbers from two runs. ( With sticky tires we could launch a lot harder ).
Huh, killer job with the performance data logging stuff… I like it. Unfortunatly, I can’t really say that I’m all that impressed with the times though, do you have any idea what it ran before? (My formula has run 13.5’s @ 100 with a cold air intake and cat back, I’d be really disappointed with 10psi boost and 13.5’s @105…)
How is that axle holding up? I’ve had my 9 bolt welded up for a while now and I just recently ripped it apart. The welds held, but the cones ripped apart into pieces, and I had much more surface area welded (the 9 bolt posi case splits apart into 2 for service, so I was able to run a bead the whole way around the cones).
The welds held for a week or so, then it started doing one-wheelers again.
That is when we did the measurement. The axle is out now and has been welded again, MUCH more this time. There were no other damage than the teeth on the spider gears.
About the performance, yes I agree thats it is no killer times, but it is not optimized for drag racing.
* It has a th400 - high first gear and it probably more hp to turn.
* Stock 2.73:1 rear gears. With the th400 it does over 60 mph at 5500 rpm in first gear.
* worn out street tires on the street and no limited slip left in the axle.
* Suspension is stock front and rear.
* We let the tranny do the shifting and it shifts to 3rd way too soon.
A 'drag racer' can probably get a lot more out of the car after some tweaking.
I know that you do wonders at the track with your cars.
What is a 'normal' time for a stock 350 TPI Camaro?
The driveability is great. WOT is a bit on the rich side and we don't use a lot of timing. There is probably more power to be found, but we want to keep it a bit on the safe side for now.
We also converted the Camaro to an environment-friendly vehicle too.
Ethanol has less energy than gas, but it also require less oxygen to burn. An engine will make the same power on ethanol, but it requires about 45% more fuel volume to get the right mixture.
E85 has higher octane.
E85 has a 4-5 times higher cooling effect.
Here in Sweden E85 cost about 30% less than gas.
We have used E85 for a while now and we get about 12 MPG and that is with a lot of WOT and not much highway.
When we converted to E85 the knock indicator went calm, almost died ... nothing. I don't think that it will be a problen running 15 psi boost on the stock engine with E85.
The problem we have right now is fuel delivery. The fuel pump is running on the edge now so we have removed the stock in tank pump. Now we are going to use two external pumps in parallel instead.
I swapped out the stock pump for a single Walbro GSS307 intank in the beginning, and it's been OK up to the 10 psi dyno runs we did, but did start dropping off from 60 psi to 50 psi up top. Just a point of reference if you need to do something thats just good enough for now, until you really crank up the boost later.
We are going to install two BOSCH fuel pumps. They each flow 58 Gallon per hour at 70 psi. The stock fuel pump only flow about 40 Gallon per hour without any pressure.
Interesting. I was looking at E85 but like you found out, the AFR is pretty low so it requires a bunch of fuel flow. In our FSAE competition it was an option and you got to hold more fuel than the teams running 94 and 100 gasoline. The best team ever in FSAE competition (Cornell) runs E85 with a turbo. The other down side to running E85 in the competition is it's smaller restrictor size... oh well, still looks like a good fuel.
What special needs to be done to a car to run E85 other than the extra "rich" AFR? Isn't it like 8:1 or something? Does it eat rubber seals, silicon, nylon?
Originally posted by askulte I swapped out the stock pump for a single Walbro GSS307 intank in the beginning, and it's been OK up to the 10 psi dyno runs we did, but did start dropping off from 60 psi to 50 psi up top. Just a point of reference if you need to do something thats just good enough for now, until you really crank up the boost later.
You know, people like to thing that it’s a simple as “this pump flows x and I need y, so I’ll be OK,” but its not even close in real life. A great example of this is what we found with my brother’s car… with a 190L/h in tank it was having problem in the 350hp range with a ½” feed line and stock, ford fuel rails. Swap to a 3/8” feed line (mostly because ½” aluminum is a PITA to keep sealed) and larger Paxton fuel rails and it was good till the 36pph fuel injectors were going static, about 500hp. It got swapped for a 255L/h (gss340) when the 77pph injectors were swapped in, but I suspect that it would have been fine for a bit more with the 77pph injectors and lower pressures (say around 35psi, the car was running a base FP of 60 with the 36’s and about 9psi boost)
Originally posted by JPrevost Interesting. I was looking at E85 but like you found out, the AFR is pretty low so it requires a bunch of fuel flow. In our FSAE competition it was an option and you got to hold more fuel than the teams running 94 and 100 gasoline. The best team ever in FSAE competition (Cornell) runs E85 with a turbo. The other down side to running E85 in the competition is it's smaller restrictor size... oh well, still looks like a good fuel.
What special needs to be done to a car to run E85 other than the extra "rich" AFR? Isn't it like 8:1 or something? Does it eat rubber seals, silicon, nylon?
Pure ethanol has an AFR of 9:1 compared to 14.7:1 for gasoline.
With the same amount of air you need 63% (14.7/9) more fuel weight. Ethanol has higher density than gasoline so you only need 52% more volume.
E85 is 85% ethanol and 15% gasoline so all together you need about 45% more fuel volume.
You only need more fuel to use E85. You could also advance timing a bit.
Ethanol is not as bad as methanol, but seals and hoses opimized for gasoline can be a problem. It is best to use hoses with a PTFE core.
One downside with E85 is that the engine is difficult to start in cold weather. You start to have problems below 50F.
So obviously gas milage is hurt, but what is the $/mile work out too?
Gas is around $2 a gallon and my average milage is 16 so if you figure 45% more fuel that'll be approximately 9, so to get the same $/mile the price of E85 would need to be around $1.12 hmm... now if I could only find a place that sold E85 .
Cool stuff. For city driving I wouldn't mind running E85 but having a 15 gallon tank I'd have to go with gas for the milage/tank. Although having a fuel cell with E85 might be cool too.
Do you use a wideband to get the 9:1 afr or is there a special o2 sensor for E85 cars?
Originally posted by JPrevost So obviously gas milage is hurt, but what is the $/mile work out too?
Gas is around $2 a gallon and my average milage is 16 so if you figure 45% more fuel that'll be approximately 9, so to get the same $/mile the price of E85 would need to be around $1.12 hmm... now if I could only find a place that sold E85 .
Cool stuff. For city driving I wouldn't mind running E85 but having a 15 gallon tank I'd have to go with gas for the milage/tank. Although having a fuel cell with E85 might be cool too.
Do you use a wideband to get the 9:1 afr or is there a special o2 sensor for E85 cars?
I start with the O2 sensor, and it might be a bit confusing.
We use a WB lambda that show AFR=14.7 for stoichmetric. The sensor measures lambda and converts lambda=1.0 to AFR=14.7 and show that. With ethanol in the tank the sensor works the same and measure lambda=1.0. The real AFR is 9.0 but the display will still show 14.7 because that is the conversion built into the meter. So you still tune to the same numbers as you would with gas.
During WOT the engine will use 45% more fuel with E85.
Part throttle is another thing. A friend of mine with a supercharged 1986 IROC managed to increase the avreage mileage when he converted to E85.
The reson is that you can lean out much more with E85 at part throttle.
At highway speed you can go to about AFR 16 on the meter, then you start to feel that it is running lean and that you loose power.
With E85 you can lean out to 18-19 on the meter before you start to lose driveability.
Awesome, I'll have to read up on it. If they start pumping E85 around here I'll have to give it a try.
I'm still a little confused about the wideband readings. Did you have to tell it you were using E85 and did it have an output for 0-1volt closed loop operation so that the wideband was reading a 9 and sending a .45mv signal to the ecu?
The lambda sensor works just like it does on gas. Same voltage for stoichmetric. The O2 sensor measures the amout of oxygen in the exhaust.
The display we use show AFR instead of lambda and that is just a calculation. The display is calibrated for gas so it will show 14.7 for stoichmetric. When we use ethanol we still tune to 14.7 on the display because that is still stoichmetric value.
The 'real' AFR is 9 on ethanol when the display show 14.7.
It would be less confusing if the display would show lambda instead because lambda = 1.0 is stoichmetric regardless of fuel.
Let me try this a different way. O2 sensors (wide band or narrow band) have no idea what the actual A/F ratio is. All they do is measure the O2 in the exhaust stream by comparing outside air what is in the exhaust (that is why you can’t seal the area that the wire comes in through). An ecm looks for a specific output voltage. We convert that to an A/F by assuming that when the V is ___, the A/F ratio is something that we guess based on the amount of O2 in the exhaust.
Originally posted by 83 Crossfire TA Let me try this a different way. O2 sensors (wide band or narrow band) have no idea what the actual A/F ratio is. All they do is measure the O2 in the exhaust stream by comparing outside air what is in the exhaust (that is why you can’t seal the area that the wire comes in through). An ecm looks for a specific output voltage. We convert that to an A/F by assuming that when the V is ___, the A/F ratio is something that we guess based on the amount of O2 in the exhaust.
Actually they don't measure anything, they create a voltage difference.
The normal O2 sensor is the simplest to explain, it has a zirconia elament that shields the exhaust side from the outside.
When the zirconia is hot it is permeable for oxygen (oxygen can travel through it), that's why the thing has to warm up first.
now what happens is, in chemistry everything want to be in equillibium. Obviously there's more oxygen in outside air than in the exhaust gas. The concentration difference between the 2 is the driving force for the o2 to pass through to reach equillibrium, this is called a chemical potential. O2 will pass through the zirconia to mix with the exhaust gas to create equillibiurm, obviously there's not nearly enough to reach this but the concentration difference between exh. & outside air determines the driving force, as said. The O2 passing through the zirconia is what creates the voltage difference, when the driving force is larger more O2 will pass through and this results in a higher voltage. At a certain point the driving force will still get higher but the max., rate of O2 passing through is reached, this is the max. voltage for the sender.
The voltage is related to the potential in a logarithmic way and is only sort of linear very close to lambda = 1 (stoichiometric value), that why you can't properly tune w/ a normal O2 sensor.
Last edited by Twin_Turbo; 08-18-2004 at 07:29 AM.
Pretty cool looking, looks like it should be enough to feed about 1400hp, but technically, you should have some kind of filter between the pump and the pickup, either a 100u sock or filter inline to protect the pumps from the crud that gets into the tank.
I don’t know what they enforce up there, but here in the states that would be illegal for a number of reasons… the big ones would be the copper lines (there are what appear to be copper fuel lines, but they are actually a nickel alloy, and no, I do not understand why copper is no good), and the lack of a proper firewall between all the fuel system parts and you. You definitely wouldn’t pass tech at a track and you’d fail most state safety inspections (for the life of me, I don’t understand how some imports like Subaru get away with running fuel and brake lines under the carpeting in the passenger compartement if no one else can).
We wanted to put some kind of screen in the tank but we did not find anything we liked yet.
I don't know why copper would be illegal. I know that some auto parts stores here in Sweden sell 8mm (5/16 inch) replacement copper fuel lines so it should work just fine even if it is not NHRA legal.
We will drill some drain holes at the bottom under the pumps in case something starts to leak. Then we are going to build a simple flat 'firewall' over the fuel pumps and that will cover most of the installation. Finally we need something to cover the fuel lines and the hole to the tank, but that should not be too difficult to do.
And a small update. With the new fuel system the fuel pressure is stable at high RPM WOT and you could feel a slight improvement. The engine was starting to lose fuel pressure before.
Fredrik decided that it was time to try a bit more boost. We have now seen 16 psi on the boost meter and it is a major differance from 11 psi. Fuel pressure is still stable and the AFR value looks fine but the engine has a severe miss at this boost level. I suspect that the stock ignition system are starting to have trouble igniting the mixture. We will reduce the spark gap and see if that helps.
Joby,
Nice job. I'm thinking of going twin Bosch/Walbro over this winter. With the stock ignition, Accel coil, 17 psi, and .034 gap, the spark would get blown out at 3800 rpms. Just a point of reference for you.
There was no room for turbo headers AND a 3.5" downpipe with the bigblock. Fredrik got creative and made a new hole near the firewall for the downpipe.
The 'new' engine is a Marine 454 bored 0.030" over.
Probably with Megasquirt and Ford EDIS8 waste spark ignition.
New parts for the rebuild:
NAL-3963523 GM Performance Parts 454ci Forged Steel Crankshaft
TRW-L2453F30 Speed-Pro Power Forged Pistons.
ESP-61353D Eagle ESP H-Beam Connecting Rods
SLP-R9590035 Speed-Pro File-Fit Plasma-Moly Piston Rings
hly-9901-209 Intake Manifold CBB http://www.holley.com/HiOctn/ProdLin.../9901-209.html
hly-9900-173 Fuel rail CBB http://www.holley.com/HiOctn/ProdLin.../9900-173.html
fms-m-9593-e303 Set of 8 injectors 150 lbs/hr
bbk-1514 Throttle Body, 80mm
SUM-G3801 water neck
MRG-4364 Thermostat, 180 Degree
CCA-11-400-4 Competition Cams Camshaft, 276/ 268-226/ 218-.525/ .514-115
CCA-7110 Competition Cams Timing Chain
CCA-858-16 Competition Cams Pro Magnum Hydraulic Lifters
CCA-1411-16 Competition Cams Magnum Steel Roller Tip Rockers
CCA-4779-8 Competition Cams Valve Spring Shims
CCA-4806-8 Competition Cams Pushrod Guideplates
CCA-612-16 Competition Cams Super Valve Locks
CCA-7154-16 Competition Cams Magnum Pushrods
CCA-741-16 Competition Cams Steel Valve Spring Retainers
CCA-924-16 Competition Cams Valve Springs
ARP-100-2901 ARP High Performance Series Flexplate Bolt Kits
ARP-135-7101 ARP High Performance Rocker Arm Studs
ARP-234-1001 ARP Cam Bolt Kits
ARP-235-2501 ARP Balancer Bolt Kits
CLE-CB743H Clevite H-Series Rod Bearings
CLE-MS829H Clevite H Series Main Bearings
CLE-SH616S Clevite Camshaft Bearing Sets
FPP-1037 Fel-Pro Performance Head Gaskets
FPP-1210 Fel-Pro Performance Intake Manifold Gasket Sets
FPP-1606 Fel-Pro Performance Blue Stripe Valve Cover Gaskets
FPP-1884R Fel-Pro Performance Oil Pan Gaskets
FPP-2703 Fel-Pro Performance R.A.C.E. Gasket Set
MIL-30710 Milodon Stock Replacement Oil Pan
MIL-18610 Milodon Oil Pump Pickup
sum-g3866 Dipstick CBB
MEL-M77HV Melling High Volume Oil Pump
ARP-135-7901 ARP Oil Pump Driveshaft Kit
TCI-399473 TCI Flexplate
SUM-402035 Fuel Pump Block Off Plate
SME-2015 Oil Filter Mount
WOW! And you guys were spinning before!! Just a note on copper fuel lines.All of the sudden they might get a crack, or they might not.That's the problem with copper.
Originally posted by Mike-91 Formula 350 WOW! And you guys were spinning before!! Just a note on copper fuel lines.All of the sudden they might get a crack, or they might not.That's the problem with copper.
there are copper alloy lines made especially for the application, and they are pretty common in Europe and on some European cars.
JoBy, you know that that big block will hurt your handling, right?
Have you measured how much room you’ve got around that exhaust like that? Can you still get a good size, 26” tall tire in there without hitting it or melting it? I’d imagine the inner wheel well is a goner either way, and you’d have to figure something out with the harness (the main harness runs right on the other side of that piece of steel, your strut tower cover is already showing signs of what can happen if you get close enough to the exhaust in a turbo car without a lot of shielding).
These are regular copper lines and we are going to replace them.
Yes ... handling ... We will probably find out how big differance it is with the extra weight.
Look at this picture. It was an extra layer sheet metal over the blue area. We got a lot of extra space with that removed so we think the piping will clear a stock size tire.
We will try to put some heat shield around the piping and also protect the wireing ( and passenger feet ).
The plastic on the strut tower was fine until we put a piece of sheet metal on the inside of the hood to protect it. That reflected more heat down onto the strut tower.
Heh… I was kidding about the handling bit… yea, it will probably affect things, but I’m betting that you guys don’t care. You’re probably just drooling over your new found cubes…
I’m eager to see what kind of clearance you have for the front tire there. I’ve thought about running it in the same place, not because of not having room in the engine bay, but to avoid making the sharp turn right behind the control arm with 3.5 or 4” pipe, and to also prevent melting the rear LCA bushing with that same assembly. Another thought that I had was cutting up the sub frame rail in that area (basically taking it’s corners off) and then boxing it to get rid of some of that tight curve.
Damn you guys work fast. I have had my iroc for 4 years, and still havent even had the motor out of the car. I wouldve liked to see the full potential of the l98 turbo motor. With suspension, rear end and gears, slicks, TC, and shift kit, that thing wouldve hauled major ***. 11s wouldve been easily reached.
Originally posted by Synapsis I have a question about running E85. Did you edit the PROM at all? Change injectors? Where'd you get the extra fuel from?
In my town there's one pump that has E85, I was pondering giving it a whirl around emissions time.
We had already installed larger injectors and done modifications in the eprom when we started using E85. We just modified the injector constant when we started using E85.