Limited slip or full spool?

B-Rode

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70 Sport Fury 383

I'll be getting 3.55s put in but can't decide whether lsd or full spool will work better for me.
A friend said my 275 rear tires are "too big" for lsd to help with traction and that a full spool is the only way to go. Spool is much cheaper as well as very strong, and I may be willing to sacrifice some low speed driveability for performance. Lsd however, would be my choice IF it is effective enough with the tires, gears and power the car will be making.
The car will be getting headers w/3 inch dual exhaust, as well as Holley 750 street demon carb w/weiand dual plane intake. Those should wake the car up quite a bit, but is lsd worth the extra $$?

Not a daily, mixed driving.

Any info helps, thanks!
 
I ran low 12's on a factory 3.91 sure grip for years with no problems at all. Still in the car now and I am building a hotter engine. I don't expect any problems. I would think that a spool would have problems on a daily driver.
 
Full spool? 383 with only the few typical external upgrades? C-body?
You bought the wrong car, son. With this car, changing out your open rear end is not called for yet. Eventually, when that time comes, a Sure-grip (that's what Mopar LSD's are called) will be fine.
 
Full spool is basically a drag strip only item, the reason road cars get limited slip or open centers is so you can turn corners without the tires dragging on the road and putting unnecessary strain on the axle shafts. (wear and tear on tires and axles etc)
Secondly, your 383, unless its putting out 375HP or more isn't going to really spin the tires on an open center too much anyway, save yourself some bucks for now and keep the open center. It wont affect your driving ability, the car is like 4000lbs and your 275s have got a LOT of traction.
 
Thanks for the input fellas. The car is really sluggish down low so I'm going ahead with 3.55s, open or sure-grip since it'll be taken apart anyway. Should really make the car a good driver around town, no chirping around parking lots for me!
 
Another option ,I did it on my 71 with an 8.25. A lunchbox locker , or a mechanical locker. It still allows you to turn without breaking a factory axle and when you load it up or are going straight it locks . For the 8.25 it was extremely simple to install , it goes in place of the spiders. I found my unit brand new on Ebay for under 150$ typically they are about 300$ .
 
Full spool is basically a drag strip only item, the reason road cars get limited slip or open centers is so you can turn corners without the tires dragging on the road and putting unnecessary strain on the axle shafts. (wear and tear on tires and axles etc)
Secondly, your 383, unless its putting out 375HP or more isn't going to really spin the tires on an open center too much anyway, save yourself some bucks for now and keep the open center. It wont affect your driving ability, the car is like 4000lbs and your 275s have got a LOT of traction.

Spool on the street, wear on tires and parts. Leave the spool on the strip only cars. Run a good suregrip or tracklock and you’ll be happy.
 
I don't care for 3.55's with a 28" tire. Annoying on the highway and not enough dig like a 3.91/4.10. compromise gear that does nothing well.
3.55 with a 25-26" tire acts like a 3.91 and is fine.
3.23 with 28" is a nice all around set up. If you want to set the world on fire then you need 3.91/4.10 but you'll hate them when you leave the city limits
 
I don't care for 3.55's
And yes to that also. Feels you're stuck in 2nd gear tops.
It appears to me to the OP is trying spend a lot of money to coax that car into laying a super fat pair of black strips of rubber pealing out from Cars n Coffee.
 
And yes to that also. Feels you're stuck in 2nd gear tops.
It appears to me to the OP is trying spend a lot of money to coax that car into laying a super fat pair of black strips of rubber pealing out from Cars n Coffee.
4.56 spool will do that right quick for cheap.
 
And yes to that also. Feels you're stuck in 2nd gear tops.
It appears to me to the OP is trying spend a lot of money to coax that car into laying a super fat pair of black strips of rubber pealing out from Cars n Coffee.

Interesting assumption. I'm looking for better low end drivability to keep up with traffic around town, 3.55 or 3.23 are my main choices (sure grip might as well include).
The question related to my original post was whether I'd get my money's worth out of some sort of locker with my particular setup, and what gears would compliment it best.
No, I don't feel the urge to "lay rubber" leaving cars and coffee. I drive the car for my own enjoyment and I post here for constructive insight.
As for my budget, "a lot of money" is toward reasonable powertrain upgrades to unchoke this SLOW, 2 barrel, one-wheel-can't-even-peel machine. I don't plan on doing much else besides the new Holley, headers+exhaust, and re-gear.
 
If the engine is healthy, the changes you list plus a 3.23 SG should give you the pep and keep the car very drive able. You should be able to power brake it easily. It probably won't spin the tires much from an idle stomp though
 
Interesting assumption. I'm looking for better low end drivability to keep up with traffic around town, 3.55 or 3.23 are my main choices (sure grip might as well include).
The question related to my original post was whether I'd get my money's worth out of some sort of locker with my particular setup, and what gears would compliment it best.
No, I don't feel the urge to "lay rubber" leaving cars and coffee. I drive the car for my own enjoyment and I post here for constructive insight.
As for my budget, "a lot of money" is toward reasonable powertrain upgrades to unchoke this SLOW, 2 barrel, one-wheel-can't-even-peel machine. I don't plan on doing much else besides the new Holley, headers+exhaust, and re-gear.
I wasn't going to comment, but here goes...

If that is truly what you want, you need to step back a little. You've been getting some bad advice about how to set up for low end.

First, let's talk about the rear... Yes, a sure-grip rear is the way to go, but it really won't give you any more low end power. All it does is make both tires spin rather that one. The spool is just plain stupid and you need to stop listening to whoever suggested that for the street. The locker is an "off road" type piece for a Jeep or truck. Look up the downsides of using one for more info. I think the 3.23 ratio is a good choice.

You have a (relatively) heavy car and building low end power is where you want to be. 3" exhaust isn't going to take you there. I'm not a fan of headers (yes, I've run them) and I really think for a C body, built for low end performance, that the high performance exhaust manifolds is the better choice. TTI makes a nice fitting 2 1/2" exhaust that will work better with your combination.

You are probably OK with the choice of intakes, but I might think about going smaller with the carb and looking at the Edelbrock AVS or AFB carbs rather than the Holley. Again, low end performance and drivability.

The "upgrades" you speak of aren't going to get you where you want to go... You have to look at the car as a whole rather than little pieces. You start adding headers, big exhaust, big carbs... They all sound good until you realize that you've now got a car that still needs a different cam, looser converter, more gear etc. to take advantage of your mods and have it run better than where you started.

If it were me, I'd just do a dual exhaust using the existing manifolds, find a stock 4bbl intake and an Edelbrock AFB, maybe recurve the distributor. From there, the 3.23 gears would be good. You would end up with a nice running car with better performance than what you have now.
 
I know not many guys on here like headers and believe them to kill low end, but there's plenty of proof they don't, and my own experience validates.
The weiand is not a great intake, oem or eddy perf is better. A 750 carb on a 383 works great when setup properly. 3" is unnecessary I'd agree, but not harmful.
 
I know not many guys on here like headers and believe them to kill low end, but there's plenty of proof they don't, and my own experience validates.
The weiand is not a great intake, oem or eddy perf is better. A 750 carb on a 383 works great when setup properly. 3" is unnecessary I'd agree, but not harmful.
The point is that cars that are put together with random parts with no regard to the end goal are going to fail and fail miserably. The combo has to work together.
 
I know not many guys on here like headers and believe them to kill low end, but there's plenty of proof they don't, and my own experience validates.
The weiand is not a great intake, oem or eddy perf is better. A 750 carb on a 383 works great when setup properly. 3" is unnecessary I'd agree, but not harmful.

Glad I chose the 750, leaves for some room to grow anyway if necessary.
Dual exhaust should open it up a bit so I'm not too concerned about the negligible powerband differences compared to perf manifolds.
What advantage does the eddy performer intake generally have over others?
 
If the engine is healthy, the changes you list plus a 3.23 SG should give you the pep and keep the car very drive able. You should be able to power brake it easily. It probably won't spin the tires much from an idle stomp though
Exactly. I'm well aware that a c body isn't going to jackrabbit start around town, never was my intention. Opening up the 383 and making for a nice driver doesn't have to take a million bucks.
 
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