I mean the muffler will be just after the resonator in the exhaust tunnel. The muffler will probably begin several inches after the shifter. I said three inches just to signify that they will need to be very close to be able to fit them both in there. I want to get the biggest resonator as possible in the available space.

What do you mean the steering column has to be repositioned? Can the core be hacked out without removing absolutely everything. I removed the AC evap so I'm willing to go to great lengths. But removing the entire dash is not happening cause it will never be the same. All the broken clips will make it creak like a haunted house even with SFC's and LTB.

 

The steering cloumn needs to drop down out of the way so that means you need to remove the guage cluster to get to the column bolts. If you have a Haynes manual you will see that the whole front dash has to come out. Then your going to need to get a pipe to connect the two heater hoses together that use to go in the heater core.

Broaner what kind of muffler are you going to use to fit under there?

 

It definitely does work.

 

Overhyped? It's a must have safety component in race cars. I wouldn't call it overhyped, maybe not necessary for a street driven Maxima.

 

That is what I was implying. Thanks. I understand the increases in safety. However it has been said already that the OEM fuel tank is very safe due to its location.

Japmax, If I pulled the heater core it would be to clean up the engine bay as well. I would completely eliminate the two hoses that run back there. That would mean I would no longer have any coolant lines besides the two rad hoses. I'd fab a plate to block where the hard lines came out near the thermostat. I'd plug up where all that junk connected on the log on the other side.

 

my brother and I replaced a heater core on my old taurus sho.. I dunno if the max is the same way, but that is a job i will never do again. It did require dropping the steering column and removing the entire dash. And then hacking and pulling at the actual heater core. Probably more of a pita than it's worth, for the 5 lbs.. even if you are trying to reduce weight..

 

I'm still not even sure if I'll do it. I'll take a look at it soon. I have half the dash out already to install the clutch pedal so it wouldn't be that much more.

 

If someone was really concerned with safety, a fuel cell is much safer in the event of a rear end collision. That could serve as a benefit for some, but the cost of a large capacity fuel cell is expensive. If you are shaving weight off the car for racing and your Maxima serves as a daily driver, then it might be something to consider.

 

But we already established that the weight saving was non existent while raising the COG. Are you one of those people that believes liquid gasoline combusts so readily like in the movies? There is a large crumple zone to absorb even extreme rear end collisions. You're more at risk of poking your eye out with scissors than your gas tank blowing up.

 

You must not know much about race cars. Every sanctioning body allows them and in the majority of actual racing series they are manditory. The main benefit of a fuel cell is that the are designed to not rupture on impact and to retain fuel if the car rolls. As for the center of gravity, who cares, the Maxima's weight distribution is biased heavily towards the front. Shifting a bit of weight to the rear isn't a bad idea.

 

As I said, I understand the safety benifits. I'm glad you allow sactioned racing to effect your opinions of what is good for our specific vehicles so greatly. Relocating a cell to the trunk will raise the COG while moving some weight to the rear. Raising the COG is usually bad. Moving weight rearward is usually good for Maximas. However, moving variable weight around isn't good. Engineers try their best to keep variable weight as close to the intended COG as possible. At that point the level of fuel has the least effect on the vehicles handling characterstics. When low on fuel nearly all of this moved weight is none existant. Since we are focusing so heavily on racing this means the rear will have more grip at the beginning of the race. This is not exactly ideal. Grip will lessen as the race wears on. At the same time the tires will also go away while using the fuel. The handling characteristics will be totally different on lap XX than they are on lap 1. This would prove to be a bear to tune without "on the fly" adjustble suspension elements. My guess is you don't have those racing type devices on your Max.

 

Opinions? So you are telling me it's someone opinion that fuel cells aren't safer? Also, you fail to take into account that fuel cells are designed to combat fuel starvation under high g loads.

Not trying to be mean, but you don't know what you are talking about. How is the fuel consumption any different in regards to a Fuel cell vs OEM tank. As you use gas, both will lighten the rear end. If you have ever taken your car to the track, you will notice that the front tires wear a lot faster. This is because of two things. First, the Maxima has foor weight distribution and terminally understeers at the limit. Second, the car is FWD and the front tires must do the turning and acceleration. Moving weight to the rear is good, again because our cars are biased more towards the front. Move as much weight as you can to the trunk, this will effectively further balance out the car to a more ideal split from front to rear.

 

Also, you don't take into account that the fuel used during say a race is removed gradually. The driver can easily account for the weight difference. It's not like 130 lbs are instantly being taken off the rear of the car.

 

Wow, your all over this. I was editing my post to make it more correct. As you see I submitted the edited version just one minute after your post. If you'll read it again you'll understand why using variable weight to alter weight distribution is a bad idea. The OEM tank is very close to the COG. I have been to the track. I do know the fronts wear more quickly. I do know this is a FWD car. I do know having gas as a weight distribution alteration is a bad idea.

I'm not saying fuel cells are bad. I agree they do wonders to combat starvation, sloshing, airation(sp?), etc... But the location being suggested is not ideal. If I were interested, which I admit that I am, I would put the cell in the location of the OEM tank. I am saying that they are hyped and overrated because people think they are hot **** when they have them. Just because you got a d@mn fuel cell doesn't mean ****. Especially if you have it in the trunk.

 

True, but the combo of tire wear and lightening the rear will substaintially change the handling. Without adjustable suspension systems the driver will not be able to drive the car with optimum handling. Why make it that much more difficult? There are so many things a diver has to think about. Why add the handling characterstics due to fuel load to it?

 

I fail to see how a fuel cell will effectively throw of the center of gravity. Our OEM tank is located below the rear passenger seat. Make an imaginery like from the top of the OEM tank to the trunk and if you mount a fuel cell correctly, it will actually sit LOWER than the oem tank. Again, a inch or two of height difference wont throw of the cars handling characteristic. In fact moving the weight further rearward will improve the weight distribution. Again, it doesn't matter if you have a fuel cell, plastic tank, or OEM tank fuel will be consumed at the same rate. Lets assume we are comparing equal capacities. The weight of the gasoline will decrease as fuel is used.

 

Wrong... COG is three dimensional. Most just think of it in terms of y values but x especially and sometimes z must also be accounted for. I'm done with this.

In case you still don't believe me. Ford seems to be finally doing something right. When you get pick up your Stang take a look under the GT. I wonder where the gas tank is? Hmmm... When you've looked all around and can't find it, look in the tunnel. Wow. It seems the gas tank and COG are in the same place. What a novel idea!

 

I might not be up on modern technology, but the driver cannot control suspension damping via the cockit of most race cars, so that's a nill point. Brake pads wear, tires wear, conditions change. A good race car realizes this and adjusts his style, simple as that.

 

I understand center of gravity. Again, you are dealing with a car that isn't weighted properly from the factory. Instead of addresing this, you are more worried about COG, give me a break.

Edit: It's been a while since I have read up on this, so I consulted a book (Going Faster! Mastering the art of race driving). Danny Sullivan and Skip Barber don't agree with what you are saying about COG.

 

Again you don't know what you are talking about. The reason why the fuel tank is placed where it is was on the 05 GT was because of safety. Go argue with Hai Thai-Tang, maybe you can fill him in on how he didn't properly design the fuel system to create an ideal COG.

 

You don't even have to spend gazzillions to adjust damping on the fly. Tein EDFC. I was referring to harder things like brake bias and sway bars.
http://www.dtmpower.net/forum/showthread.php?t=44230

Moving gas is not the proper way to alter an improperly weighted vehicle.

 

You can put a brake bias valve inside any car.

Honestly, go get the book I referred to earlier. It will explain to you how to setup a race car. Realizing the COG is great, but it can be changed and adjusted MANY ways. Seating position affects it. Lowering the car affects COG. You assume that the spring engineers took this into account, but it could be off. Etc Etc.

 

Cog adjustment for one inch higher fuel cell,im taking sunroof out

And also my fuel cell full will weigh less than my oem empty or the same.

 

That's a stupid idea unless you install a new MC or somehow bypass the original proportioning valve. You should never have 2 proportioning valves in-line.

 

Where did you hear this? I can cite numerous sources that show installation of a proportiong valve without changing the MC or bypassing the OEM valve.

 

"We’ll start here with three of the most basic rules regarding proportioning valve installation and selection.

1. If you have the deeply-rooted need to install your own adjustable proportioning valve, be advised that they should NEVER be installed if the factory unit is still in place. Proportioning valves in series with one another can do nasty, unpredictable things!"

http://www.stoptech.com/whitepapers/...ing_valves.htm

 

Well yeah you can. You just cut and flare a brake line and install it. Not sure if you need one per wheel though. But the thing is, something like the Tilton unit can only reduce the force going though it. Not increase. So let's say you have a big front BBK and stock rear brakes. Severe front bias. So you install two Tilton units and reduce the amount of force going into the front calipers. Thus restoring the bias. But IMHO that is counterintuiative? Why reduce the front braking force when you just went to the trouble of increasing with a bbk?

Now the other option is to install a completely adjustable bias adjuster that can control the amount of braking force to the calipers. But unfortunately, you have to get rid of the stock bias adjuster. Which unfortunately is located inside either the master cylinder or the ABS actuator. (at least the 3-gens are this way).

 

Interesting...I knew it wasn't advised to run a proportioning valve to the front brakes. A couple of major magazines show a PV installed in tandem with the stock MC for the rear brakes to control bias.

 

I have a question. If the oem PV is in the MC. And the oem rear bias is let's say 30%. How is a porportioning valve installed downstream going to adjust bias in any postive way? Most of not all people would want to increase the bias because of a bbk install etc... The only thing you could do is decrease the rear bias.

 

When you're dealing with a track car (where these valves are designed to be used), they usually install dual MCs with a balance bar in between.
you set it to the most rearward you'll ever expect to need by the balance bar, then put the adjuster valve in the cockpit so the driver can adjust during a race if needed.

As for the fuel cell issue above, NONE of you really understand why the car is designed the way it is. I'm not going to go into too many details, but suffice it to say that
1. mounting a cell in the trunk is higher off the ground than the factory tank, raising vertical COG, and being farther back also moves it rearward. this affects more than just roll centers, but also changes the car's polar moment (how it rotates) as well as how the car leans through corners. This affects suspension geometry, sway bar settings, weight distribution, shock damping, brake bias, and several other factors..

wanna do a test? let your gas tank run just about empty, then throw a few huge bags of sand in your trunk where the fuel cell will be located. don't just think about the weight of the cell and the fuel. also need the pump, hoses, vapor return crap, etc etc etc. there's about 30lb more crap you have to move in addition to just the tank and fuel.

2. collisions.. those fuel cells are generally not DOT approved- they may be safer in a race environment, but they're not safer on the street- not by any means. the gas tank is in the middle of the car's chassis to protect it in the event of a collision. a race car has frame rails and part of the roll cage around it to protect the fuel cell in the event it gets hit. the car also has a fire suppression system for the chance that fuel leaks and catches fire. I doubt your street car will have all of those safety precautions taken care of.
Drag cars mount them in the trunk with no protection because they're not driven on the street and don't have to worry about being rear ended.

3. emissions. have you SEEN all the crap that's hooked to these fuel tanks? good luck moving all of that stuff over. it's not just a fuel fill, supply, and return line. there's about half a dozen hoses on them for emissions as well..

4. good luck passing ANY state inspection with that thing mounted in your trunk.

 

You are correct. Again, this whole arguement is pointless because if you are building a track car, you would properly bias the brakes using a handful of methods.