Need advice
03-14-2010, 07:22 PM
#1
On The Tree
Thread Starter
iTrader: (2)
Join Date: Apr 2009
Posts: 118
Likes: 0
Received 0 Likes
on
0 Posts
Need advice Gonna put a built rearend under my car soon...Need some advice.
I am trying to do some homework on all the rearend options for my 98 z28. I'm new at this. All I know right now is that I will likely break my stock rearend soon and will be replacing it regardless, before or after that occurs...It has never given me a single problem...yet. I would like to put a stronger, narrowed rearend under that car. Could i get some advice if I tell you a little about my car and my end goals?
A little about my car and my goals:
The car will ultimately be a street car, built in a way that I will also be able to drag race well on the weekends. It will have street suspension, not drag suspension. It will have 17x9.5 front wheels and 17x11 rears and 315 series Nitto DRs.
I want the rearend narrowed in order to run a deep dish wheel. It might end up with a set of drag wheels later, strictly for track use. I know at that point it might progress more towards a drag suspension with different springs/shocks, but I am trying to keep this car as streetable as possible, with the ability to carve corners and stop quickly, yet still hook up well and have fast ETs at the strip.
I understand that EVERYTHING is a trade off and u can't have the best of both worlds, but I'm shooting for somewhere in the middle. For now, street car, street suspension, drag race tendencies.
As far as power output, I have not yet planned whether or not I will later force feed the car, or bolt on more NA go-fast parts. My goal for the car is 500+ hp/lb ft on the stock bottom end. If that gets boring I may get crazy and tear it apart, in a quest for more power since everyone know power is addictive...but I digress. Right now 500+ is the goal. Its a stock internal LS1/T56 combo with a few bolt ons, including Fast toys ram air, Pacesetter LTs with ORY and Magnaflow exhaust, no cats. The car has never been on a dyno since I've owned it and has a stock tune for now.
Now down to the issue at hand: Rearend.
I want a rearend that can handle all the abuse I'll ever be able to give it with my 6 spd (don't we all). I don't like the idea of adding weight to the car with a heavier rearend, but if its necessary i will.
It seems that depending on the setup, a fab'd 9" cab be built to weigh the same as stock, if not less. I am leaning away from a 12 bolt since I don't think it will be strongest enough in the end. It seems ppl are breaking them more often than a 9 inch or Dana S60. A few other things I dislike are gear wine/howl, which seems common with the 12 bolt, and I dislike the way the torque arm mounts to the rearend on the 12 bolt. It seems the way the stock torque arm attaches to the rearend is better.
Who actually makes the Dana S60? Correct my terminology if I'm wrong. It seems that is the heaviest of the bunch, yet the strongest with its 9.75" ring gear?
That leads me to question the difference in power losses between the different rearends?
How much power loss is there with a stock 10 bolt vs a fab'd 9 inch vs a Dana S60?
I will NOT be running a spool, so I need to do some more research on the best LSD...advice/experiences?
I also need to research what the best gear ratio will be for my goals, which I'm sure will be dependent on whether I go force fed or NA. Ideas?
I have seen that there are many different rearends available, made by many different companies and combinations of housings and center sections so I'm trying to keep it all straight and make sure I know what I'm talking about. I have read many threads on forums but I'm still learning and would appreciate all the advice you could give. Thank you.
I am trying to do some homework on all the rearend options for my 98 z28. I'm new at this. All I know right now is that I will likely break my stock rearend soon and will be replacing it regardless, before or after that occurs...It has never given me a single problem...yet. I would like to put a stronger, narrowed rearend under that car. Could i get some advice if I tell you a little about my car and my end goals?
A little about my car and my goals:
The car will ultimately be a street car, built in a way that I will also be able to drag race well on the weekends. It will have street suspension, not drag suspension. It will have 17x9.5 front wheels and 17x11 rears and 315 series Nitto DRs.
I want the rearend narrowed in order to run a deep dish wheel. It might end up with a set of drag wheels later, strictly for track use. I know at that point it might progress more towards a drag suspension with different springs/shocks, but I am trying to keep this car as streetable as possible, with the ability to carve corners and stop quickly, yet still hook up well and have fast ETs at the strip.
I understand that EVERYTHING is a trade off and u can't have the best of both worlds, but I'm shooting for somewhere in the middle. For now, street car, street suspension, drag race tendencies.
As far as power output, I have not yet planned whether or not I will later force feed the car, or bolt on more NA go-fast parts. My goal for the car is 500+ hp/lb ft on the stock bottom end. If that gets boring I may get crazy and tear it apart, in a quest for more power since everyone know power is addictive...but I digress. Right now 500+ is the goal. Its a stock internal LS1/T56 combo with a few bolt ons, including Fast toys ram air, Pacesetter LTs with ORY and Magnaflow exhaust, no cats. The car has never been on a dyno since I've owned it and has a stock tune for now.
Now down to the issue at hand: Rearend.
I want a rearend that can handle all the abuse I'll ever be able to give it with my 6 spd (don't we all). I don't like the idea of adding weight to the car with a heavier rearend, but if its necessary i will.
It seems that depending on the setup, a fab'd 9" cab be built to weigh the same as stock, if not less. I am leaning away from a 12 bolt since I don't think it will be strongest enough in the end. It seems ppl are breaking them more often than a 9 inch or Dana S60. A few other things I dislike are gear wine/howl, which seems common with the 12 bolt, and I dislike the way the torque arm mounts to the rearend on the 12 bolt. It seems the way the stock torque arm attaches to the rearend is better.
Who actually makes the Dana S60? Correct my terminology if I'm wrong. It seems that is the heaviest of the bunch, yet the strongest with its 9.75" ring gear?
That leads me to question the difference in power losses between the different rearends?
How much power loss is there with a stock 10 bolt vs a fab'd 9 inch vs a Dana S60?
I will NOT be running a spool, so I need to do some more research on the best LSD...advice/experiences?
I also need to research what the best gear ratio will be for my goals, which I'm sure will be dependent on whether I go force fed or NA. Ideas?
I have seen that there are many different rearends available, made by many different companies and combinations of housings and center sections so I'm trying to keep it all straight and make sure I know what I'm talking about. I have read many threads on forums but I'm still learning and would appreciate all the advice you could give. Thank you.
03-15-2010, 03:19 AM
#2
11 Second Club
iTrader: (8)
Join Date: Jan 2002
Location: SILSBEE TX
Posts: 1,782
Likes: 0
Received 0 Likes
on
0 Posts
I like a 9 "
it will handle what you are planing easy.
with 6 spd I would go 4.10
"10 bolt vs a fab'd 9 inch vs a Dana S60?"
I think the 9" will lose 8-10 hp and the Dana about 12-15 hp, I do not think you would break eather
I like Detroit lockers,I ran one 6-7 years back in the '60 strip/street, have been running one in the 10 bolt strip/street for the last 4-5 years, and have a 9" with locker waiting on the side thinking the 10 bolt may go at any time
just my .02' Johnny
it will handle what you are planing easy.
with 6 spd I would go 4.10
"10 bolt vs a fab'd 9 inch vs a Dana S60?"
I think the 9" will lose 8-10 hp and the Dana about 12-15 hp, I do not think you would break eather
I like Detroit lockers,I ran one 6-7 years back in the '60 strip/street, have been running one in the 10 bolt strip/street for the last 4-5 years, and have a 9" with locker waiting on the side thinking the 10 bolt may go at any time
just my .02' Johnny
03-15-2010, 09:34 AM
#3
On The Tree
Thread Starter
iTrader: (2)
Join Date: Apr 2009
Posts: 118
Likes: 0
Received 0 Likes
on
0 Posts
Thanks for the input.
I found an interesting article where a certain magazine installed several rear ends under the back of a chevelle with small block 383 for dyno pulls and testing. Rear ends they used include 12 bolt, 9 inch, and S60. Check it out. I'm not advertising the mag, I just thought it was cool. On the dyno charts, I like what the S60 is putting out towards the end of the rev range vs where the 9 inch's power starts to fall off. Just a cool comparison.http://www.carcraft.com/techarticles...wap/index.html
I found an interesting article where a certain magazine installed several rear ends under the back of a chevelle with small block 383 for dyno pulls and testing. Rear ends they used include 12 bolt, 9 inch, and S60. Check it out. I'm not advertising the mag, I just thought it was cool. On the dyno charts, I like what the S60 is putting out towards the end of the rev range vs where the 9 inch's power starts to fall off. Just a cool comparison.http://www.carcraft.com/techarticles...wap/index.html
03-15-2010, 09:59 AM
#4
I have a QTP 9" in mine with a spool and drive it on the street, No complaints, I started with a detroit locker and hated that POS. The 9" does cost power, and is fairly heavy although you can get lightweight options, But the trade-off is knowing that the thing can take whatever you are gonna throw at it. Good luck finding a lsd for the 9 inch that will take alot of track time, I have read so many post about busted trac-locs its ridiculous. I like the fabbed nine too but it was way out of my budget.
When you research your gears you are gonna find alot of guys saying run 4.11 with a sixspeed. I took that advice when I first did my swap. I didnt like it, yeah the car accelerated faster but there was really no time to enjoy pulling thru the gears, just shift shift shift. Maybe the guys with stock power like those gears but when you put more into it I hated it. I ended up putting 3.75s in and that really balances my car out.
When you research your gears you are gonna find alot of guys saying run 4.11 with a sixspeed. I took that advice when I first did my swap. I didnt like it, yeah the car accelerated faster but there was really no time to enjoy pulling thru the gears, just shift shift shift. Maybe the guys with stock power like those gears but when you put more into it I hated it. I ended up putting 3.75s in and that really balances my car out.