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-   -   Tilton set up issue. (https://www.rx7club.com/race-car-tech-103/tilton-set-up-issue-1091137/)

wcr2k11 10-20-15 08:32 PM

Tilton set up issue.
 
Hey guys I have tilton 74 series brake and clutch set up on my fd 20b swap and the brakes
Perform terrible, the pedal is super hard and very minimum pedal travel.
I bleed the system and still.
Please help. Thank you.
Note: no abs.

Brent Dalton 10-21-15 09:51 PM

Most likely your master cylinders are the wrong size.

wcr2k11 10-21-15 10:23 PM


Originally Posted by Brent Dalton (Post 11982437)
Most likely your master cylinders are the wrong size.

What size is recommend
Thank you

almoststockrepu 10-22-15 06:19 AM

It depends on how much fluid travel is necessary. Size of caliper, line, and bore of master. If you call Tilton they will guide you in the right direction.

valley 10-22-15 06:58 AM

Ignoring for a moment that you may have a bad bore size setup:

A hard pedal on manual brakes means several things. You have no air in the system (good). You are getting pad engagement (good). You MAY have a bad pedal ratio (bad).

I'm running a 7:1 ratio on my manual brakes on my FC and that's about as high a ratio that's recommended for a variety of reasons. Most don't recommend below a 6:1 for most production vehicles either. Also, manual brakes will feel differently than assisted. Once you have full engagement there should be no more movement in the system and the difference in braking will simply be how hard you're pressing the pedal.

I highly recommend verifying the pedal ratio on your setup and otherwise calling Tilton for advise. You'll need things like vehicle weight, balance, caliper volumes, etc. It is not an easy setup so call people in the know.

23Racer 10-22-15 08:14 AM

I spoke with the Wilwood Brake engineer about the brake setup on my Cougar and he asked about everything mentioned above. Its amazing how in depth you need to go to build a very good non-boosted race brake setup. Find out what you have (calipers, master cylinder bores for both and pedal to pivot ratio). Then when you speak to the guys at Tilton or Wilwood or wherever, they can make a correct recommendation.

If you don't, you will spend bags of cash replacing parts, getting frustrated and then give up. I can also tell you that the average pedal effort for my manual braked race Cougar is not at all different than my boosted RX7.

Eric

wcr2k11 10-22-15 08:48 AM

Very appreciate every advice.
I'll put all set up info togheter and call Tilton.
For you that has this kind of set up.is it grate advantage in braking using this set up.
im not a track guy mostly used on the streets will like to know how the will perform in a emergency braking senerio.

DaveEstey 10-22-15 12:35 PM

Try this form:
Dual Bias Calc.

The owner, Todd Cook, is a friend of mine and a great help for this stuff.

Brent Dalton 10-22-15 08:38 PM

As others have said, there are alot of factors at play. What are your current master cylinder sizes? Current brake calipers? Assuming you have a 6.2:1 overhung pedal assembly as that seems to be most common? I've been down this road and it took a while to get it dialed in. Let me know what you have and I'll make some recommendations.

Dave, that is an awesome calculator!

almoststockrepu 10-23-15 06:31 AM

Brent, what was the fluid capacity of the remote reservoirs that you were running on the yellow car. I remember talking to you about it when you were at Dans place one day but i cant remember.

Brent Dalton 10-23-15 07:06 AM

If I remember correctly, I have the 6oz ones. Is this Jeff?

almoststockrepu 10-23-15 07:12 AM

Yep its me. Just now started getting back on 7club. I had to make a new account.

wcr2k11 10-23-15 11:40 AM

Brent,
I have the 6 oz. I'm waiting on Ken from Tilton for the
recommended set up for my car. However if any of you has a tilton set up
That is working fine for the streets.
Please share if don't mind.
Thanks Aydin M.

rollcoal 10-25-15 08:29 AM

interested as well

Brent Dalton 10-25-15 10:24 AM

Aydin,
I need your set up information. Jeff was asking about reservoir size for his own reasons. It's irrelevant to us right now. I need your brake set up information (current calipers, pedal box ratio, and master cylinder sizes) before I can help.

Here is a basic explanation I posted in another thread a couple years ago:

"You can reduce the stiffness by reducing the size of the master cylinders. In theory, the softer it is the more modulation it allows for (ie more precise through a larger range of motion). That being said, a stiff pedal offers confidence for a lot of people. You also have to take into account brake system compliance. You want a system that has the largest range of pedal travel with it hitting lock up at the end of it's range; while taking into account a safety margin for fluid boil, system compliance, etc... so you can ensure 100% braking at all times. Oh BTW, without ABS, that point of lock up constantly changes due to all kinds of variants to include brake pad material, tire material and size, environmental conditions, etc, etc, etc... Correctly sized master cylinders will allow you to make large changes, your balance bar(can be adjusted while stationary at the pedal box or on the fly if you have a remote knob) will allow your fine tuning. Most of the time, the balance bar will allow you to get where you need to be. Again, I would really try to keep ABS."

Here is a little information on my set up that is in my race car: https://www.rx7club.com/race-car-tec...-875889/page6/

I've been through a few set ups over the years. I'm eventually going to try to re-install the abs or retrofit a standalone abs system out of another car/platform.

You may already have your starting point from tilton, if not, let us know your set up and I'm sure there are some of us here that can give you some suggestions. :bigthumb:

Brent Dalton 10-25-15 10:30 AM


Originally Posted by almoststockrepu (Post 11982921)
Yep its me. Just now started getting back on 7club. I had to make a new account.

Hope the married life is treating you well. I think your crumb snatcher is due around the same time as ours. I'm about to paint the nursery. I'd like to say the times have changed, but they really haven't. Going to mess around in the garage basement after that and am hitting the track next weekend :D Repu project looks badass! Just saw pics on fb. Hope to run into you guys in Nashville one of these days when we are around.

wcr2k11 10-27-15 05:01 PM


Originally Posted by Brent Dalton (Post 11983556)
Aydin,
I need your set up information. Jeff was asking about reservoir size for his own reasons. It's irrelevant to us right now. I need your brake set up information (current calipers, pedal box ratio, and master cylinder sizes) before I can help.

Here is a basic explanation I posted in another thread a couple years ago:

"You can reduce the stiffness by reducing the size of the master cylinders. In theory, the softer it is the more modulation it allows for (ie more precise through a larger range of motion). That being said, a stiff pedal offers confidence for a lot of people. You also have to take into account brake system compliance. You want a system that has the largest range of pedal travel with it hitting lock up at the end of it's range; while taking into account a safety margin for fluid boil, system compliance, etc... so you can ensure 100% braking at all times. Oh BTW, without ABS, that point of lock up constantly changes due to all kinds of variants to include brake pad material, tire material and size, environmental conditions, etc, etc, etc... Correctly sized master cylinders will allow you to make large changes, your balance bar(can be adjusted while stationary at the pedal box or on the fly if you have a remote knob) will allow your fine tuning. Most of the time, the balance bar will allow you to get where you need to be. Again, I would really try to keep ABS."

Here is a little information on my set up that is in my race car: https://www.rx7club.com/race-car-tec...-875889/page6/

I've been through a few set ups over the years. I'm eventually going to try to re-install the abs or retrofit a standalone abs system out of another car/platform.

You may already have your starting point from tilton, if not, let us know your set up and I'm sure there are some of us here that can give you some suggestions. :bigthumb:

Hello Brent,
Not sure on my pedal ratio,all I know is a 600 series. As calipers,they are stock and 74 series m cylinders 74 series 3/4 core.
I checked your link and would like to know the specs of your set up. Also looks like you have a bigger diameter brake lines. What's the diameter on those b.lines.
Thank you. Aydin.M.

Brent Dalton 10-28-15 12:33 PM

When I get home from work, I will post more from my computer.

wcr2k11 10-28-15 02:47 PM


Originally Posted by Brent Dalton (Post 11984911)
When I get home from work, I will post more from my computer.

Thank you.
Very appropriate it.

Brent Dalton 10-28-15 10:47 PM

If you are 3/4 on both master cylinders, they should be pretty soft already. I'd go with whatever tilton recommends. I think they'll recommend 7/10 and 5/8. Otherwise, I'd go a little smaller and see how they feel if you don't hear back from Tilton with a recommendations.

My brake lines are -3AN(standard brake line size). My MC's are 7/8 and 3/4 (74 series) and I have a 6.2:1 ratio of my pedal assembly. I have a good bit of travel. I have stoptech ST40 fronts and 99spec rears.

almoststockrepu 10-29-15 06:08 AM


Originally Posted by Brent Dalton (Post 11983557)
I think your crumb snatcher is due around the same time as ours.

:rofl: Amanda didnt think that was too funny but i thought it was hilarious lol

I am running the exact same setup. 3/16 seamless line, 3/4 front, 7/8 rear, 6.2:1 pedals. Have yet to try it but from everyone i can find info from, that's what they recommend for my setup. Wilwood brakes, Tilton everything else

wcr2k11 10-29-15 09:14 AM

i might simplIfy myself going back to stock without ABS.


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