LS1 Swap Rear end options

[Ryan1212]

FWIW i've heard that the stock gas tank is superior to most fuel cell setups as it doesn't really suffer from starvation like alot of 'murican cars do AND it effectively raises the center of gravity of the car. gas is, like, 8lbs per gallon, so... math

in any case, i'd just use the stock fuel tank. odds are BMW spent alot more money in keeping that shit more puncture/flame resistant than any aftermarket company did throughout their entire lineup

A surge tank solves the fuel issue very efficiently. You can run one with the stock tank or a cell. I am mainly getting rid of my tank because my driveshaft was super close to the gas tank and I had to space it down with 4 washers on each bolt to gain enough clearance to not rub (using the adapter from jagsthatrun). This winter I am installing the rear camber correction and raising the subframe so all even more reasons to get rid of the tank being in the way (also leaves space for routing awesome exhaust exits through the side rockers).

[bmk]

I have some weird heavy vibration from somewhere in my drive line above 120. it really freaking annoying I think my diff is ever so slightly crooked or something. I had to go with a custom drive shaft because I was afraid of it hitting the gas tank.

[e30_302]

(also leaves space for routing awesome exhaust exits through the side rockers).

Do not do that. The rocker panels are very structurally necessary and significant, do not cut into them. Run it under them if that's what you want.

[iflytii]

Do not do that. The rocker panels are very structurally necessary and significant, do not cut into them. Run it under them if that's what you want.

Yep, good advice. We will run them through the rockers on our race cars only because those cars are extensively caged. Even then we still reinforce the area around where we cut for the pass-thru.

I've not had any clearance issues with a 3" drive shaft, or dual exhaust with a stock fuel tank. I've had starvation issues when low on fuel with a stock tank, but there are ways to remedy that. I'm hoping the Holly hydramat might be another good solution starvation as well. If you haven't seen this stuff, check it out: https://www.youtube.com/watch?v=N_jsSPRUTSA

[The Dark Side of Will]

gas is, like, 8lbs per gallon, so... math

6 lbs per gallon.

Water is 8 lbs/gal.

[kristov]

No issues with the 188 diff in my car but I have twisted a couple cv joints into submission.



For the tach setting, it's pretty straight forward. I invested in a HP Tuners license so I could continually make tweaks, but any good tuner can do this. For the specific settings it is documented well here:
http://www.hptuners.com/forum/showth...t=tach+setting

That looks like the smaller half shafts (318i, 320i etc.) and they break very easily.

[TeXJ]

http://www.answers.com/Q/Does_water_..._than_gasoline

Ok so I learned something today

https://answers.yahoo.com/question/i...7102428AAGCyPB

[jalopi]

6 lbs per gallon.

Water is 8 lbs/gal.

[Ryan1212]

Yep, good advice. We will run them through the rockers on our race cars only because those cars are extensively caged. Even then we still reinforce the area around where we cut for the pass-thru.

I've not had any clearance issues with a 3" drive shaft, or dual exhaust with a stock fuel tank. I've had starvation issues when low on fuel with a stock tank, but there are ways to remedy that. I'm hoping the Holly hydramat might be another good solution starvation as well. If you haven't seen this stuff, check it out: https://www.youtube.com/watch?v=N_jsSPRUTSA

I more so meant through the actual side of the car like this, called it the rocker because well close enough. The sheet metal there isn't doing anything to help.


Obviously the bottom rocker rail/pinch welded area is structural, and my cage is going to basically attached above and below the 2 cuts for the exhaust.

Also, gasoline is about 6lb/US gallon, it's mass is about 0.75x the mass of water, hence why gasoline separates and floats on water.

[jalopi]

oh i believe you, i just don't like dark very much