Power Max on Rear-end?
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 845
Likes: 12
From: LAKE BARRINGTON IL
Power Max on Rear-end?
Hi,
Got a 69 corvette, original 350 car. I am upgrading to a BBC, probably 550 hp & tq.
How much power can the stock rear actually take?
To upgrade, where do you go/how do you solve?
Thanks,
Ron
Got a 69 corvette, original 350 car. I am upgrading to a BBC, probably 550 hp & tq.
How much power can the stock rear actually take?
To upgrade, where do you go/how do you solve?
Thanks,
Ron
Burning Brakes
Joined: Feb 2011
Posts: 849
Likes: 0
From: Woodland California
The rear end will handle the power no problem.
It's the extra weight that will need to be handled.
Rear sway bars will need to be added.
Bigger front sway bars.
Heavier springs and shocks all the way around.
After all that you still drag around all of that extra weight so you will need more breaking power.
Build a 400 Cubic inch small block.
Take it out to a 427 or bigger.
The 383 is no slacker either.
This could be cheaper in the long run.
What are you going to do with all that extra power anyway?
Ralph
It's the extra weight that will need to be handled.
Rear sway bars will need to be added.
Bigger front sway bars.
Heavier springs and shocks all the way around.
After all that you still drag around all of that extra weight so you will need more breaking power.
Build a 400 Cubic inch small block.
Take it out to a 427 or bigger.
The 383 is no slacker either.
This could be cheaper in the long run.
What are you going to do with all that extra power anyway?
Ralph
Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
The rear end will handle the power no problem.
It's the extra weight that will need to be handled.
Rear sway bars will need to be added.
Bigger front sway bars.
Heavier springs and shocks all the way around.
After all that you still drag around all of that extra weight so you will need more breaking power.
Build a 400 Cubic inch small block.
Take it out to a 427 or bigger.
The 383 is no slacker either.
This could be cheaper in the long run.
What are you going to do with all that extra power anyway?
Ralph
It's the extra weight that will need to be handled.
Rear sway bars will need to be added.
Bigger front sway bars.
Heavier springs and shocks all the way around.
After all that you still drag around all of that extra weight so you will need more breaking power.
Build a 400 Cubic inch small block.
Take it out to a 427 or bigger.
The 383 is no slacker either.
This could be cheaper in the long run.
What are you going to do with all that extra power anyway?
Ralph
How much power the rear will handle is dependant on how sticky your tires are. I have a zz502 with BFG's and they'll spin before it hurts the rearend.
If you put drag radials on it, don't dump the clutch too often.
Burning Brakes
Joined: May 2009
Posts: 1,232
Likes: 6
From: Tucson AZ
St. Jude Donor '12
Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
Without going into a lot of detail, unless someone requests me to, the diff will not hold up.
Mike
P.S. I agree with bashcraft. There is no comparison between a 500 hp smallblock and a 500 hp bigblock.
Mike
P.S. I agree with bashcraft. There is no comparison between a 500 hp smallblock and a 500 hp bigblock.
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 845
Likes: 12
From: LAKE BARRINGTON IL
Thanks guys for the info!
Power is always fun...I see power just like p*nis size...does anyone ever complain that it is too big?.....JK
I have a 454 mk iv block. I have bounced around a 427, 454, or 489. Now it is down to 454 or 489. leaning more to the 489 bc if I do it, I wanna do it once and right.
right now the car has a 348 big block (replacement...odd) and runs like a dog. it seems to be ok with weight distribution, ie springs, but I cannot be for sure.
so the biggest weak link I am seeing (i am sure there are more) is the rear end. so why wont it work?
(mike)
Bashcraft, was your car originally sb car? did you do anything to the rear?
what approx power do you have? trans?
Thanks,
R
Power is always fun...I see power just like p*nis size...does anyone ever complain that it is too big?.....JK
I have a 454 mk iv block. I have bounced around a 427, 454, or 489. Now it is down to 454 or 489. leaning more to the 489 bc if I do it, I wanna do it once and right.
right now the car has a 348 big block (replacement...odd) and runs like a dog. it seems to be ok with weight distribution, ie springs, but I cannot be for sure.
so the biggest weak link I am seeing (i am sure there are more) is the rear end. so why wont it work?
(mike)
Bashcraft, was your car originally sb car? did you do anything to the rear?
what approx power do you have? trans?
Thanks,
R
Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
Originally a small block car. When I bought it in 1979 it had a 1970 CE LT1 motor in it. That motor is now under my bench and I have the zz502 which is rated at 500 hp. I have an M20 trans and a 3.08 rear gear. I think the slippery tires is why I haven't had any problems.
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Burning Brakes
Joined: May 2009
Posts: 1,232
Likes: 6
From: Tucson AZ
St. Jude Donor '12
You're right, my mistake. My thought on a small block is parts tend to be less expensive.
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
69 still used different parts for bb and sb.
69 sb cast iron carrier small window versus
69 bb nodular iron small window
10-18 spider gears
slotted clutches
After 1970 carriers went to the large window design and thicker bodies. 78-79 being the best.
spiders gears changed to 10 - 17 teeth
bearing caps were re-deisgned
But if you want to drive the bb to its full potential then this will not be enough. You will need:
30 spline stub axles
31 spline spindles
3" halfshafts
spicer joints
solid clutchpack
better gears
hardened spider gears and cross shaft
Check with ajrothm here and ask him about his upgrades
Mike
69 sb cast iron carrier small window versus
69 bb nodular iron small window
10-18 spider gears
slotted clutches
After 1970 carriers went to the large window design and thicker bodies. 78-79 being the best.
spiders gears changed to 10 - 17 teeth
bearing caps were re-deisgned
But if you want to drive the bb to its full potential then this will not be enough. You will need:
30 spline stub axles
31 spline spindles
3" halfshafts
spicer joints
solid clutchpack
better gears
hardened spider gears and cross shaft
Check with ajrothm here and ask him about his upgrades
Mike
Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
Thanks guys for the info!
Power is always fun...I see power just like p*nis size...does anyone ever complain that it is too big?.....JK
I have a 454 mk iv block. I have bounced around a 427, 454, or 489. Now it is down to 454 or 489. leaning more to the 489 bc if I do it, I wanna do it once and right.
right now the car has a 348 big block (replacement...odd) and runs like a dog. it seems to be ok with weight distribution, ie springs, but I cannot be for sure.
so the biggest weak link I am seeing (i am sure there are more) is the rear end. so why wont it work?
(mike)
Bashcraft, was your car originally sb car? did you do anything to the rear?
what approx power do you have? trans?
Thanks,
R
Power is always fun...I see power just like p*nis size...does anyone ever complain that it is too big?.....JK
I have a 454 mk iv block. I have bounced around a 427, 454, or 489. Now it is down to 454 or 489. leaning more to the 489 bc if I do it, I wanna do it once and right.
right now the car has a 348 big block (replacement...odd) and runs like a dog. it seems to be ok with weight distribution, ie springs, but I cannot be for sure.
so the biggest weak link I am seeing (i am sure there are more) is the rear end. so why wont it work?
(mike)
Bashcraft, was your car originally sb car? did you do anything to the rear?
what approx power do you have? trans?
Thanks,
R
For what it's worth, I agree with the folks who say that it depends on traction. I have a friend who had a pinto with a pretty warmed over 302 transplanted into it. Bone stock differential, never had any problems with it because he also had the bone stock tires on it. Not for very long, tho, he needed new back tires on a pretty regular basis, but they were cheap, and it was a lot of fun!
Scott
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Give me any stock C3 Vette with slicks and a 4 gear on a prepped track and I will show you how p'ssed off guys get on a Sat night when they close the lane down and then have another half an hour wait while the try and find anymore parts in the remaining good lane.
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
Anyone who tries to race with slicks and a stock diff is taking a big chance. Big block, small block, auto, 4 spd, it doesn't matter. I've seen them all break. But I went to the trouble of finding out why.
I assuming you know how much hp it takes to get a full-bodied, street legal vette into the tens. Explain to me then how I can take an 80-82 Dana 44 with stock internals and have two cars running mid tens and one running upper nines. All three belong to forum members here.
The original poster asked if his diff would hold up. I say no. I explained why. Where are you seeing so much BS? Do you even know the difference between a big window and a small window carrier? So some guy shows up at a track with a worn out diff and blows it up on the line. So now all stock diffs are bad?
Mike
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 845
Likes: 12
From: LAKE BARRINGTON IL
Guys thanks for the info.
Scott- WOW. Yes, it is a W code...good call. It is ok. Only a few people actually notice, so it really doesnt mean anything. I would keep it, but it is a dog. it is rated at 265 hp. yes it is torqey, but puts out at 3500 rpm, so really only have 2 gears of pull. (it is all original engine from 1959...gonna sell full setup from carb to pan...FYI...if interested)
Mike- thanks. that does explain...so just rebuild the stock rear stronger then... this does make sense. where do you suggest I find these parts?
Bashcraft-nice setup...that baby has got to fly! Pretty car to boot!
Just to clarify....I am looking for something to have tons of fun with on the road...maybe road course....not really looking to drag it....like a month ago, when a C2 BBC took off like I was standing still-not cool. Mine sounds good, but that is it!
I had a 70 chevelle SS 396, putting 425 out. It was alot of fun....but even that I wanted more. I will keep the stock rims...maybe more rubber on width, but not slicks. I do agree that they will probably spin before anything.
Thanks guys! I will check with a few rear guys about doing the work. What is a good price for parts? work?
R
Scott- WOW. Yes, it is a W code...good call. It is ok. Only a few people actually notice, so it really doesnt mean anything. I would keep it, but it is a dog. it is rated at 265 hp. yes it is torqey, but puts out at 3500 rpm, so really only have 2 gears of pull. (it is all original engine from 1959...gonna sell full setup from carb to pan...FYI...if interested)
Mike- thanks. that does explain...so just rebuild the stock rear stronger then... this does make sense. where do you suggest I find these parts?
Bashcraft-nice setup...that baby has got to fly! Pretty car to boot!
Just to clarify....I am looking for something to have tons of fun with on the road...maybe road course....not really looking to drag it....like a month ago, when a C2 BBC took off like I was standing still-not cool. Mine sounds good, but that is it!
I had a 70 chevelle SS 396, putting 425 out. It was alot of fun....but even that I wanted more. I will keep the stock rims...maybe more rubber on width, but not slicks. I do agree that they will probably spin before anything.
Thanks guys! I will check with a few rear guys about doing the work. What is a good price for parts? work?
R
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
Now lets take a 355 and a 454 both making 500 hp. The 454 will cost much less to build than the 355 at the 500 hp level, no comparison in torque, and will have better street manners. So you build a big sb, 383, 400, 406, 417. Not worth the expense. So build a bigger sb, 427, 434. Aren't you now in bb territory? But with more restrictions. Intake and exhaust runner size. Headers and intake selection. What are the advantages? Weight? 100 lbs max worst case. Cubic inches is cubic inches. Why not build a 454, 496, 502, 540? Much better hp/$ ratio. Now your weight difference is less than 50 lbs.
I have nothing against 427 and 434 sb motors. I just can't justify the expense to build one. I don't have a good reason to build one. Nothing against the people that run them. If you like them then I am happy for you. They are just not for me.
Mike
Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
Sure. But you are comparing apples to apples in different grocery bags. Unless you have a very specific reason for building a 427 sb, why would you do this build?
Now lets take a 355 and a 454 both making 500 hp. The 454 will cost much less to build than the 355 at the 500 hp level, no comparison in torque, and will have better street manners. So you build a big sb, 383, 400, 406, 417. Not worth the expense. So build a bigger sb, 427, 434. Aren't you now in bb territory? But with more restrictions. Intake and exhaust runner size. Headers and intake selection. What are the advantages? Weight? 100 lbs max worst case. Cubic inches is cubic inches. Why not build a 454, 496, 502, 540? Much better hp/$ ratio. Now your weight difference is less than 50 lbs.
I have nothing against 427 and 434 sb motors. I just can't justify the expense to build one. I don't have a good reason to build one. Nothing against the people that run them. If you like them then I am happy for you. They are just not for me.
Mike
Now lets take a 355 and a 454 both making 500 hp. The 454 will cost much less to build than the 355 at the 500 hp level, no comparison in torque, and will have better street manners. So you build a big sb, 383, 400, 406, 417. Not worth the expense. So build a bigger sb, 427, 434. Aren't you now in bb territory? But with more restrictions. Intake and exhaust runner size. Headers and intake selection. What are the advantages? Weight? 100 lbs max worst case. Cubic inches is cubic inches. Why not build a 454, 496, 502, 540? Much better hp/$ ratio. Now your weight difference is less than 50 lbs.
I have nothing against 427 and 434 sb motors. I just can't justify the expense to build one. I don't have a good reason to build one. Nothing against the people that run them. If you like them then I am happy for you. They are just not for me.
Mike
Yeah at one time I was going to build a big SB... Once I priced the parts, machining etc...it was easily $8-10k in parts...That was assembling it myself and no dyno time... That would have been around 600hp.... I decided even with the additional cost of the conversion parts, I could get a big rat in there cheaper.... I ended up with a fully assembled 657hp dynoed, carb to pan, turn key, SHIPPED 496 big block with all Scat 4340 rotating assy for $7900.... Ofcourse plus the cost of the conversion stuff, but since the conversion is done, I have room to grow to even bigger/more power....Were as a 600-650hp small block is basically maxed out if your running on pump gas.... For me it was worth the work of the conversion....
But no doubt you can build some nasty nasty running small blocks.....It just costs a lot of money...
