In this post, I will explain how, and what parts you will need to do a 4×100 hub conversion on a US model 1981 Honda Accord. This is a common question that I hear people asking how to do. The main issue is that the stock car’s lug pattern is 4×120, and this leaves you with a very limited, and hard to find selection of wheels. 4×100 provides the perfect opportunity to pick a more custom set, and will upgrade your brakes to vented rotors, rotor over hub, and a more modern caliper setup. In the rear, you get a bonus rear disc conversion.
Please note that I have not done this swap on any earlier Accords, and so this may not work on all models. Cross reference part numbers between your car and the 1981 model to see if any interchanges will work for you.
Lets get started on doing the front conversion. To make this work, you’ll need an assortment of parts from various other Hondas.
- 1982-83 Accord Front Hubs
- 1982-83 Accord Front Wheel Bearings (Same as the stock wheel bearings)
- 1986 Accord Front Calipers
- 1989 CRX Si Front Rotors
- 2-4 washers to space out the brake calipers from the caliper bracket
1981 Accord Knuckle and Hub Assembly
1982 Accord Knuckle and Hub Assembly
As you can see from the above diagrams, the two cars are set up similarly. In fact, the 1981 and 1982 both use the same wheel bearings. So you can probably see how easy this swap is.
First step is to remove the front calipers and simply pull the hubs and wheel bearings out. You can successfully use a hub puller to get the hub out of the wheel bearing first if you want. Then the wheel bearing will need to be pressed out. I was successfully able to use a front wheel bearing adapter set. I picked mine up at Harbor Freight for around $120. Alternatively, I’ve found shops that will do this for you if you bring them the knuckles for about 1/2-1 hour of labor charges.
Once you are down to the knuckle, you’ll want to press the new bearing and hub back in. Then slip on your CRX rotor (over the hub, so now replacing them is easy). The only trick is, once you bolt on the 86 Accord calipers, you’ll need to put a washer or two behind each caliper bracket bolt to space the caliper bracket out and line up with the new rotor.
Once you’ve got everything assembled, you should have a nice looking setup like this. Nicely upgraded from the original.
The Rear Conversion
And now for the rears. All the parts all comes off of any 2g Prelude, DX or Si. The Si simply has slightly bigger calipers.
- 83-87 Prelude Rear Rotors
- 83-87 Prelude Rear Wheel Bearings (They are actually the same as the stock bearings)
- 83-87 Prelude Rear Calipers
- 83-87 Prelude Rear Caliper Brackets
- 83-87 Prelude Rear Brake Hoses
- 2 machine washers about the same size as the inner wheel bearings
So here we have some parts diagrams of the Accord and Prelude. Look closely at the spindle and notice how they are basically the same. The wheel bearings are even the same between both setups. So swapping them out is as easy as stripping down the Prelude to the spindle, and putting all the parts on the Accord spindle. The only caveat is that the inner wheel bearing seal on the Prelude drums will rub on the Accord spindle. To solve this, read on below.
Accord Brake Setup
Prelude Brake Setup
Now that you understand how they compare, here’s some pictures and an explanation of what I did to make everything work.
First I tore down the Accord brakes clear to the spindle. Here’s what the actual spindle looks like:
Bolt on the Prelude caliper bracket.
Assemble your wheel bearings and rotors. Place your appropriately-sized washer on the wheel bearing to space it away from the spindle. Don’t forget the inner bearing seal.
Install the rear rotors onto the spindles.
So as you can see below, the tab for bolting on the Prelude e-brake cable bracket hits the strut. You can’t use the Prelude e-brake cables anyways, so you can just cut them off.
Also when bolting on the calipers, you’ll notice the lower control arm bolt is in the way of the lower caliper bolt. You have two choices here, either remove the bolt from the lower control arm, or simply bolt the caliper to the bracket before you install it.
The last thing to figure out is the e-brake connections. Since the Accord e-brake cables come in at 90 degrees to the hub, and the Prelude e-brake cables come in perpendicular to the hub, you’ll need to do some adapting on the cable brackets.
What I wound up doing is cutting the Accord bracket off, and welding it to the Prelude bracket at 90 degrees. This allows it to pull at the proper angle, and is almost perfectly the right length. Mock up your cables and line everything up so that there is some tension on the actuator, otherwise you’ll end up with slack in the cable.
Here are the brackets welded together.
And here they are installed.
Once it’s all bolted together, and your brake lines connected, you will have a nice rear disc, 4×100 conversion.
So now that you’ve upgraded your rotors to bigger, vented discs, upgraded to bigger calipers with a more modern slider design, and converted the rears from drubs to discs, you get the added bonus of a 4×100 conversion, and being able to add a large selection of wheels to your car. This modification is win-win, and with the bolt on ability from the off-the-shelf parts, it’s super easy and cheap!