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How much work involved in converting to 4-link solid axle??
Finding limitations with the stock suspension with power limitations, etc... I am curious how many $$$ and how much work to install a 4-link? Also, how terrible would the handling be? This is going to be a daily driver, but eventually would like to be around 600' #'s of torque. I noticed that the HD half-shafts on the Van Steel site are big bucks leading me to this discussion!
Those that have experience or knowledge of this mod...please chime in.
Thanks!
Last edited by BlackRocket; Oct 17, 2017 at 02:22 AM.
Finding limitations with the stock suspension with power limitations, etc... I am curious how many $$$ and how much work to install a 4-link? Also, how terrible would the handling be? This is going to be a daily driver, but eventually would like to be around 600' #'s of torque. I noticed that the HD half-shafts on the Van Steel site are big bucks leading me to this discussion!
Those that have experience or knowledge of this mod...please chime in.
Thanks!
I would love to ditch the independent rear suspension and install a Nova rear axle or something similar. As I never drive it hard in corners I have no need for an independent rear suspension.
More work than building your IRS up to handle the power. Can’t comment on the cost of converting but there is plenty of stuff out there to build a bullet proof IRS. I am having mine done now.
I would love to ditch the independent rear suspension and install a Nova rear axle or something similar. As I never drive it hard in corners I have no need for an independent rear suspension.
To each their own and I say this with the utmost respect: that statement made me cry on the inside.
Personally I am all about handling. Straight line speed does very little for me.
Last edited by PainfullySlow; Oct 17, 2017 at 11:48 AM.
Here is a photograph of the 3-link in my Factory Five 33 Hot Rod which is an upgrade option from their 4-link suspension. It could be done, would not be cheap and much more than upgrading the IRS.
My Factory Five could run "circles" around my C3 with the IRS any day.
Someone recently updated their thread on the forum who was doing a frame off resto/mod on a 68 convertible that did a tubed 4-link.
They posted some awesome photographs.
Last edited by OldCarBum; Oct 17, 2017 at 12:24 PM.
I don't know the cost of upgrading the IRS, but the cost of the 4-link kit to install your solid axle in a C3 was about $1150 from Auto-fab race cars. The kit included everything except the rearend. The instructions were excellent. I used a Dodge 8.75 rear. A local machine shop narrowed the housing and the axles are from Dr. Diff. You could go junk yard hunting and find a rear that would not need narrowed. I even re-used the drum brakes. This gave me an excuse to buy a mig welder from Harbor Freight. You can spend more money, but that was not my goal. I am very pleased with the result.
But what is the cost as compared to a four link. I did my 77 and the parts were around 5k. And I did it myself.
It would cost more then a solid axle conversion no question. Tom is preparing to sell and retire, no secret there so those interested in this type of build would be advised to buy direct from him before things change. Depending on the extent of your build you probably saved about $3000 in labor cost by doing it yourself.
The cost to have someone do the frame conversion is only part of it. You'll need to purchase a new diff housing, have it narrowed, new axles, ring and pinion, posi differential, and all the essentials. I would imagine the parts and labor costs to build the new rear end to take 700 hp will be about the same as building the IRS.
The cost to have someone do the frame conversion is only part of it. You'll need to purchase a new diff housing, have it narrowed, new axles, ring and pinion, posi differential, and all the essentials. I would imagine the parts and labor costs to build the new rear end to take 700 hp will be about the same as building the IRS.
Cost depends on the level of experience and labor the car owner can provide. A lot of the solid conversions I have seen on forums were done by the owner. I agree to get all the work done will add up fast. The level of the 12 bolt build cost will also vary depending on the detail of the work. Make up a simple spreadsheet to compare part cost, labor, shipping, subbed out work. The projected end use should be considered as that will have a huge impact on build type. I have friends with c2 & c3's in the 600-700hp range and run the car hard but not as abusive as a primary drag car.
Cost depends on the level of experience and labor the car owner can provide. A lot of the solid conversions I have seen on forums were done by the owner. I agree to get all the work done will add up fast. The level of the 12 bolt build cost will also vary depending on the detail of the work. Make up a simple spreadsheet to compare part cost, labor, shipping, subbed out work. The projected end use should be considered as that will have a huge impact on build type. I have friends with c2 & c3's in the 600-700hp range and run the car hard but not as abusive as a primary drag car.
I've just started researching the capabilities of the stock IRS in our corvettes. I've heard that the stock IRS will easily hold up to 600hp if you drive safe and sane with roll on acceleration and not hole shots from light to light. I've been told rebuilds with improved half shafts and u joints with some internal upgrades can be driven hard and not fail. But if you plan to auto cross, road race or run drags the cost will sharply increase to upgrade for the additional abuse.
This is my first IRS car and I'm learning.
I've just started researching the capabilities of the stock IRS in our corvettes. I've heard that the stock IRS will easily hold up to 600hp if you drive safe and sane with roll on acceleration and not hole shots from light to light. I've been told rebuilds with improved half shafts and u joints with some internal upgrades can be driven hard and not fail. But if you plan to auto cross, road race or run drags the cost will sharply increase to upgrade for the additional abuse.
This is my first IRS car and I'm learning.
600hp, stock 10 bolt- stock built, yeah you could drive it ok if you don't push it at all but why build a 600hp car and not USE it?
Shock loading breaks these cars, they were designed around 350 - 400hp not 600hp. If someone told you the stock IRS will hold up to 600hp in performance use they were selling you a story. A properly blueprinted 10 bolt I would say to 450hp, a real super 10 into the 550 range, 600 and over - Tom's 12 bolt IRS which can be built in 1350 or 1480 configuration. If you go that far go with the 1480 but know it requires the full axle to axle build. These are all different builds internally so you will have to look into them to learn the differences.
At that power level you need to look at the driveline from the flywheel to each wheel. Trailing arms, there are various types on the market. Outer axles - Tom's 31's would be best with his 134" wall 3.5" 1350 1/2 shafts. If you were to go to 1480 then you have to use his 1480 shafts which are shorter. Frame stiffeners, weld in gussets, possibly solid mounts, adjustable shocks, stiff spring, driveshaft- we run 1350 driveshafts, and the full Tom's IRS package. Tom has it all in his online catalog. Also plenty of guys have converted to 9" and are happy.
You can Cryo treat parts for added strength so depending on application/budget it might be something to look at. You are 100% correct, cost for building these adds up fast. If you can build a engine, have access to machines, measuring tools, and PATIENCE you can build one at home with some coaching. I have taught guys around the world on building diffs. You are also very wise to do your homework before you open your wallet.
Everything has a breaking point, we sheared Spicer solid 1350's inner and outer with one dead hook. Sometimes it cost less to have a nice street vette and a less valuable drag car to beat up but everyone has a different desire. Good luck with your decisions
Tom's 12 bolt IRS which can be built in 1350 or 1480 configuration. If you go that far go with the 1480 but know it requires the full axle to axle build. These are all different builds internally so you will have to look into them to learn the differences.
How much work involved in converting to 4-link solid axle??
