Hello,

I recently swapped my 1999 Civic CX to a 5 lug setup from a JDM ITR (36mm); I found that the brakes are incredibly spongy and almost non existent after the conversion.

What I did:
Swapped the front knuckles, hubs, calipers, etc from a JDM ITR
Swapped the rear drums for the disc brakes from a JDM ITR (control arm, calipers, etc.)
Swapped the E brakes lines from a JDM ITR for the new rear discs.
Swapped all the caliper brake hoses with a Stoptech braided kit meant for a 1999 Civic Si.
Bled the calipers in the follow order with a vacuum bleeder (mityvac):

• Rear Right
• Rear Left
• Front Right
• Front Left

And did not find any leakage in the lines.
I did not swap my Brake Master Cylinder for the ITR/CTR/GSR 1 inch master cylinder.
Myy questions then are the following:

1. Is it possible to keep the stock Master Cylinder with such a 5 lug swap? Or is it not possible given the increase in size/fluid?
2. When bleeding the brakes, are you supposed to start the car first? It seems the brake pedal is stiff when the car is off but the moment I start and drive it I lose all stiffness and they do not engage well. I am wondering if I should bleed it while its on then.

​​​​​​​Thanks!

 

Its best you find the ITR mc.

 

I'd try re-bleeding the old fashioned way with a friend to pump and hold the pedal while you work the bleeders or by yourself using a bottle with some clean fluid in it and a tube. I've found that while vacuum bleeders do the majority of the work, they never quite get it 100%. If it's still spongy, find a 1-inch MC and start again.

 

Your pedal is going to be low with the master cylinder. Go with a 1" MC and all should be good. I see you figured out the correct bleeding order. They'll never bleed if you use the traditional method as the brakes are set up diagonally. Each circuit does a front and rear wheel on opposite sides so in the event of a failed brake line you'll still have both front and rear brakes.

 

Have you test driven the car yet? Breaking in the pads and rotors will usually improve pedal feel and also let you evaluate actual stopping performance.

 

The ITR brake booster is different at least as far as the part numbers go. I have run into issues before trying to mix and match them even when the MC would bolt up. The length of the rod inside booster that pushes on the MC is often a different length.

 

Did it go right into place or did you need to tighten the nuts up to draw it tight against the booster?

If the pin in the booster is too long it gets the piston in the MC from returning all the way lot letting fluid go back down the hole inside the MC. You're not going to see any leakage as there is no fluid transfer between the MC and brake booster. Check for leaks at all fittings. If there are none I would suspect either the booster is the problem or the proportioning valve.

Proper proportioning valve is from a '98 - '01 JDM ITR. The closest to correct USDM prop valve will be from a '98 - '01 Integra RS. USDM ITR doesn't have a prop valve as it's got ABS.

 

I actually have the ITR mc with the stock civic booster. Pedal feels fine.

 

Same. 97 LX booster with ITR 1" master cylinder. Bolted right up. I would say the pedal is on the meh side of fine. Perfectly ok for daily running around but not the most inspiring at high speeds.

 

Once i replace all the rubber lines with stainless steel, I'll be good.

 

I'm surprised that the problem goes away when you plug both front and rear ports on the driver's side. That leak is definitely a problem. I would take a close look at the flex hose before touching the hard line and see what the seat looks like, I'd tend to blame the new hose over the hard line that was previously fine unless the flare looks very flattened out.


Yes you can shorten the hard line.


You may have a slight leak at the front caliper. I'd take a close look at the bleeder.


Also, be very careful that you don't ruin the seats in the proportioning valve plugging those ports with bolts. I really wouldn't recommend doing it that way. I'd go with a very short flared piece of brake line with the end crimped or brazed.

 

Replace the caliper.

 

Option a - continue to deal with the bullshit.
option b - on last email letting them know that you should not be paying any refund charges for defects and that you will be requesting a chargeback.

BUT you'll need to read up on their policy on returns and any exchanges.