Corvette calipers
 

I was in Chicago last night and went to go see Oz. (sorry Bob kinda quick trip)

Anyway we were discussing brake options. I have been thinking of just getting Wilwood 4 piston calipers for my Dana 44. But Oz seems to think the Corvette calipers would be cheaper yet still yield four pistons like I want.

Does anyone know what year model the vette Caliper would work with the dana 44 out of a '86 grand waggy? I would like to compare prices between the vette's and Wilwoods.

(Yes! Yunny, I know these trucks are not sports cars.:lmao: ) I just like the idea of having more braking force.

What kind of braket would you use to mount the new fixed calipers vs the old floating calipers. Will

I am sure I could fab up something from some 1/2" flat stock, but these are some issues I am trying to work out.

I guess a better question would be what are the pros and cons of this thought?

I like the idea of being able to use the stock location for the caliper mounting but I would like the "best bang for the buck" also

i think it was the early 80's vette calipers that would bolt on to a waggy D44. no new brackets are needed..
the calipers are $$$ and run something like $100+ each. I think AK and Yunny looked into the mod a few months ago.
Parts mike would have the exact year if everyone else (including me) has forgotten.

Thanks Chuck! I thought that there was a direct bolt on vette caliper, but I was beginning to second guess myself as usual.

$100+ for the caliper is what I expected. the Wilwoods which I was all but decided on are $136 ea. so maybe a few penny's here or there will help.

I'll contact Parts Mike and find out what he knows. Thanks again!

Do you need a bigger master cylinder to push those calipers?

should be ok with the stock master cylinder. stock tacoma brakes are 4 piston

i am going to give partsmike a call tomorrow and see whats up...stopping 37's is getting slightly dangerous at highway speeds:)


just reviewing some past threads on the topic... mid 70's corvettes had the 4 piston brake calipers..... front and rear...not sure what one to exactly get, but the prices for a loaded caliper from kragen for example goes from 100 -160 bucks... if wilwood is selling direct bolt ons and that are piston for 139 a piece...that sounds like a killer deal


for more info... look at 1975 chevy corvette

Yes you do!
:D

It is already planned to do the chevy master cylinder converstion at the same time. I just need to figure out the caliper delimma.

I am almost "reverse engineering" this stuff. Starting backwards and working to the front. I made the decision to do the larger brake system, knew I needed a bigger M.C. can't decide on type of rotor until I decide on Caliper so there is where I am stuck.

Thanks for your input though. I do appreciate it.

the stock toyota M.C is a dual port M.C but the chevy/dana calipers are larger than stock Toyota calipers and require more fluid pressure for greater force. The Chevy masters are I "believe" a one inch bore where as the Toyota bore is 13/16". I know that doesn't sound like much but as you said stopping 37" at highway speed is a bit dangerous so any advantage you can achieve should be worth it. at least that is the way I am approaching this.

the wilwoods I found were through Jeg's for about $139 (if I remember right, it has been about a month since I looked at my catalog) but I still need to contact them to make certain that they have an application for the Dana. As you can imagine what application I found was for street/race car application

I also emailed Parts Mike yesterday to see if he knew what corvette application may work. Just waiting on his reply

The larger bore does not give you more pressure but more fuild with less travel on the peddle. The chevy MC would give you less pressure then the toyota one. The larger the bore, the less the pedal needs to move but the less pressure you get.

Why not a M.C. out of a F(Z)J 80/100?

That is a good point, I think my main objective or thinking on this was to get more fluid or have a larger resevoir.

I just can't see a stock toyota M.C giving you the same amount of fluid pressure as a full size truck's M.C. A toyota is a much smaller/lighter vehicle thus engineered with a braking system to match that need. A full size truck is much heavier and requires more stopping force. But I do understand your comment about more fluid less travel.

I am not argueing, just trying to reason this out. you bring up very valid comments.

Not sure? I think I have possibly heard some using them. But to me, I would think going with a Chevy or GM part would be easier to find if you were on the road or trail, and needed a quick fix.

That is purely hypothetical though, I could be completely wrong :confused:

What rotor would you use?

There is an age old debate about slotted or drilled rotors versus vented rotors and such.

But the main thing for me is to make sure the rotor matches the caliper. you have different calipers for different thicknesses of rotor. that is the reason I am holding off on rotor selection until I get the calipers.

Hell! just this morning I decided to go after work and look at the stock rotors to actually see if they maybe worth using. I automatically disqualified them when I bought the axle, but after thinking about everything, It may save some coin to start out with them if possible. I am just not sure how thick the stocks were or if over time they have warped.

Ideally I am wanting a 1" drilled rotor, for more material and venting of the product gases of the pads. But like I said I am waiting until I decide on the calipers.

I would consider a slotted AND drilled rotor, but I think for our trucks and for rock crawling, the needed amount of heat build up in the friction process needed by the brake system would be self-defeating. Due to the slotted/drilled rotors ability to maintain lower tempertures. Although the main purpose of these types of rotors is not to disappaite heat but rather dispell harmful gases produced by the heat/friction between the pads and the rotors.

(hows that for a rambling post? :D )

if you find a caliper thats four piston, and bolts onto the dana 44 axle...the stock master cylinder is fine

stock tacoma calipers are four piston

does anyone know the diameter of the stock tacoma caliper pistons? someone that hasnt swapped yet and ditched their stock junk?



BEAR :)

ha ha!
:D

I actually had my calipers off last week for an emergency pad change, but did not think to measure the piston.

To venture a guess I would say maybe 1.5 maybe 2" diameter. Something also to consider though is with GM type calipers the overall size of the caliper moves the pistons further apart than the stock caliper. I don't know for sure if that has anything to do with stopping ability but it makes me stop and wonder if maybe it does.

You know three years ago, when I decided to SAS I figured right at $5000 would give me a good swap. I am fairly certain that I have already spent $4000 on this damn idea, but last night figured up how much more I still need to finish…came up to an estimated $1934 in parts including labor for the gear swap. did I screw up my math in the beginning or what? I guess not settling for cheaper parts here and there has really cost me huh? both in time and money.

Also realized Valentines day was the actual three anniversary of my endevor…bought my axle on Feb 14 2002! How time flyes when you are struggling. :lmao:

BTW! I am still flirting with the idea of using the stock disk brakes from the front for the rear. means even more coin out the pocket in the end. At least the wife is on board about getting this done…basically tired of hearing about it constantly ( my plan is working! :xdevil: )

Chevy could be using larger pistons on the caliper. Also I do not know how power brakes (never looked in to it) work so difference in the power system could affect the pressure greatly. What I was saying about the pressure decrease with increase diameter in the MC is strictly just looking at the hydraulic leverage. The rotor diameter and pad area also change the braking

Again, more good food for thought. Let me give you the e-article I am working off of. Please note that I do not know this guy from Adam, but what he says made sense to me. I could be following the wrong pied piper on this one. But like I said it made sense to me when I read this a few times.

http://home.4x4wire.com/erik/4runner/brakes/

You brought up another factor with this last post. Power brakes. Toyotas have a dual diaphram booster at least most tacos do. this helps because you are starting with a "high level" of leverage on the peddle with it. But if you start with a low volume of fluid ie. stock toyota M.C.combined with larger braking components then you are loosing some of your leverage from the power assist. If you have larger rotors and brake components such as with the Dana/spicer axle you need to regain some of that leverage, especially since you have larger parts to operate and stop.

I would also think the higher volume of fluid the GM M.C provide will maintain a lower temperture also preventing brake fade at those grueling points and conditions.

Let me know what you think? In doing my SAS I want a nice truck, but to me 80% of having a nice truck is having a safe truck. Okay maybe more like 90-95% but you get the idea.

right now, I like my brake peddle firm so I don't want to loose any of that. Although I know with 37" tires and a solid axle up front. I am going to too regardless. Just like to keep as much as I can.

I am enjoying this dialog, just goes to show everyone two people can have a diffference of opinion and still remain civil on the boards!

I am going to quote the web site a few times because he is saying the same thing as me but in different words. It sounds like that total area for the Chevy caliper (2 larger pistons) is larger then the Toyota caliper (4 smaller pistons) so you need to upgrade the MC to push more fluid to the calipers. I think the problem that people are having is that you ratio is so high that the pedal cannot move far enough to build up the needed pressure.

"I put in the 1-1/4" master and this definitely got rid of the mushy pedal. My brake pedal was now rock-hard and could not be pushed all the way to the floor no matter how hard I tried. Locking up the front tires was now finally possible.
The only disadvantage was that it also increased the pedal-effort needed to stop the truck"

This makes sense because the MC is pushing more fluid but you decreased your mechanical advantage because of the larger diameter.

"Hydraulic pressure and leverage is directly dependant on the piston surface area at each end of the system (master end and caliper end). You have a relatively small piston in the master cylinder and large ones in the calipers. This gives your foot a leverage advantage.

If you want to increase your braking power for a given amount of foot power, then you can either increase the piston size of the calipers, or decrease the size of the master. This comes with a tradeoff though- your pedal will feel "softer," and if you make too big of a change, the master cylinder may not be able to push enough fluid to the calipers to build up full pressure before the pedal bottoms out. This is the problem I had with the big D44 calipers and small Toyota master.

Conversely, if you want a firmer pedal, then you can decrease the caliper size or run a bigger master.

Other ways to increase the mechanical advantage of your brake system are smaller tires, bigger rotors, and increased brake pedal ratios (longer pedal)."

This just explains why the pedal gets harder to push and why it does not travel as far. The smaller diameter MC will allow you to apply more pressure but the stroke of the MC is going to limit the pressure that you can get with one pump. I think you could lock up your tires with the stock MC but you would have to pump the brakes to get the needed pressure. According to his site the Tacoma’s should have a 8.6:1 ratio if the MC is 13/16 and the calipers have ~ 4.46in squared of area. When you go to the stock D44 calipers you would need to go to a 1" bore to keep the 8.6:1 ratio. If you are going with the corvette calipers, you should find the measurements to see if you would need an even larger bore to keep the same ratio. Now if you have the same hydraulic ratio, same diameter rotor, and same size pad as stock you would have the same brake feel and performance as you do now. You also mentioned that you are thinking about adding disc brakes to the rear. If you do, make sure the MC is set-up for a vehicle with disc brakes front and rear. If you have a MC that is set-up for front disc and rear drum but you have disc brakes in the rear it will cause a spongy feel again because the pads move too far away from the rotor when you are not braking.

awesome post PT....

I think when you step up to larger than 35 inch tires, even with 35s i guess to a lesser degree, you need to seriously think from a safety perspective about stopping your truck. with the 37's the very first impression i got was my truck didnt stop as well...

so my plan.... rear disc with correct aftermarket BPV, or PSPV, or lspv, or PMS..or whatever you want to call it today, and maybe swith out to 4 piston calipers in the front. 4 pistons just apply more surface area to the clamping surface of the pad to rotor..so weeeeeeeee...better stopping i hope....

Great! between your advice and the article, I feel a lot better about what direction to be heading. You have helped tremendiously. thank you.

It also sounds like you are confirming some of th practices within that article so like I said before, without knowing the author, there was still some doubt as far as if it actually had accurate information to follow. But again it seems that you think also that it can be followed.

Thanks I owe you one! :xbeer3: :clap:

Anthony, I wanted to say here, that it looks like we both have the same concerns. If you want to work on this through emails together, or on the board let me know. Two sets of eyes finds info much faster than one set (or something like that)

My game plan right now is to look at my axle this weekend and take measurements of the mounting of the Calipers. Take that information with me to work on Monday and call Jegs and/or Summit and see exactly what calipers they have that will work. My priority on those calls is to find a 4 piston caliper that will be a direct bolt on. I'll will definitely let you know all information I find out afterwards.

Like Bear, I would say just under 2" of diameter for the Tacoma caliper piston.

The real issue with generating brake pressure is the booster, not the master cylinder. The booster is where the pressure difference is created. Having more fluid from a larger master cylinder does help, but the booster is leading factor.

awesome Bear. Disc all around would be sweet. Aor I think its coming out with a rear disc setup. that has got to help as well.

Bigger brake booster.

I don't think it would be to difficult seeing there is a lot of disc out there with your bolt pattern like the 99 and newer chevy fullsize trucks. You could even use the front rotors possibly.

As far as MC.......how big is the tundra's MC? I would assume that would be the most likely to mount up not including models like the Land Cruiser which has 4 wheel disc brakes and alot heavier than a Tacoma.

I think you may have twisted that up a might. The larger bore does give you more pressure on the pad because the area of the piston is greater (Area = pi R Sq) and pressure exerted = Area X Pressure applied so total pressure = pi R Sq X PSI. Because the total bore of the caliper cylinder is larger by comparison to the old caliper, the cylinder volume is also larger requiring more displacement of the cylinder attached to the brake pedal to equal the same linear displacement of the caliper piston.

A larger bore on the caliper side will give you more pressure but on the MC side the smaller the bore the more pressure. The only problem is that if the bore is too small on the MC side or the bore on the caliper side is too big you will not be able to move the pads enough to get full pressure. So you need to look at the hydraulic ratio and make sure you don't go to far away from the stock ratio.

Tuns have a 13/16" MC

Tundra booster has a different bolt pattern Its essentially the same bolt pattern as early GM MC's

Good readin on 4x4wire on the ratios of different bore MC's- Link

Good link, thanks.

what link Dick?

are you feeling ok?

Blind Anthony....
 

Re-read TMS2U's post (above the Dick's)...

Hint: the link is in line #3...

thats not a link

thats a hyperlink


The DIck needs to recognize....i am going to beat THE DICK :)"

Whatever....You mistake me for someone who cares....

Loaded 'Vette calipers from Schuck's/Kragen/Checker:

http://www.partsamerica.com/ProductL...rchfor=Caliper

You just saved me a phone call I was about to make, thanks! But the link kinda gave me a wild goose chase. What part numbers did you use? I called my local shop about a month ago and was given 16-7000-16 and 16-7000-17, but neither came up in their search.

I was trying to confirm the price I got was for loaded or not. Does $128.88 and $118.00 sound right?

You lookin for some of me, PUNK? BRING IT!!!

I just went through the "Replacement Auto Parts" link and filled in the info for a mid-70s Corvette.

What are the $128 and $118 for? Rear and front, respectively? Which brand?