Zmanco Posted September 15, 2006 Share Posted September 15, 2006 Like I said before, I would check that my rears weren't too tight, and I'd make sure I had no air in the front lines. After that suspicion moves to the proportioning valve. I don't believe there is any way to adjust it: it either works properly or it doesn't. I haven't had issues with mine so I can't give you advice from my own experience, but you could either replace it with another from a JY, or replace it with an adjustable unit. Given you've changed the braking power of the fronts, I think the adjustable would be a good idea anyway. That's the direction I'm headed. Link to comment Share on other sites More sharing options...
jmurphz33 Posted September 18, 2006 Share Posted September 18, 2006 Wow.. very thorough, and extremely helpful. Nice detail, this helps a lot. I'll be looking to Modern Motorsports for some adaptors. Link to comment Share on other sites More sharing options...
stagefumer11 Posted September 19, 2006 Share Posted September 19, 2006 OK... Im unsure if im reading this right. IM doing this upgrade on my hr30 skyline. Im using the 280z Hub/carreir and bolting that to the hr30 spline ( same as the 280z. R30's use a crappy Hub/rotor combined setup) Everything matches up the same as it would on the 280z. So this means i can use the maxima rotors ? with out needing a spacer ect?. What od are the maxima rotors ? 250mm...260 ? ect ? Link to comment Share on other sites More sharing options...
blueovalz Posted September 20, 2006 Share Posted September 20, 2006 Quote:Originally Posted by nicedat you need less effort to push two pistons than four, so this would give more power to the rear. Not true: you need less VOLUME for 2 pistons vs. 4. For a given level of pressure, the 4 piston caliper with its greater piston area will exert MORE force on the pads/rotor than the 2 piston caliper. Piston bore area (or piston area) is what is important. An you'll find very little difference between 1, 2, and 4 piston caliper effectiveness if all pistons have the same total area (except for the single or dual floating piston arrangements that must have their piston area multiplied by 2 in order to compare to "fixed" calipers). Link to comment Share on other sites More sharing options...
stagefumer11 Posted September 21, 2006 Share Posted September 21, 2006 ok guys, What do i need to do. Im doing this upgrade my problem is, is trying to find the right rotor. As i stated in the above post. Im using 1979 280z Front hub carriers. These are going onto my skyline as the main spline is the same. Same with all the mounting points. ect.... Im using the s12+8 Vented disk Calipers off a 1988 hilux/4runner Which really need the ofset of the rotor to be pushed back. MY problem is at the moment is when lineing the gear up on the rotor ( i marked out caliper mounting points to see where the rotor will sit in the caliper) I came accros that the caliper hits the center of the 280z hub. :(. Now im dumfounded. Either way. it looks like i have 10mm extra clearance on the caliper in the Rotor O'd. With these maxima rotors what out diamiter are they ? Hat height ect ? IM getting frustraited and confused also about this. Does this upgrade not apply to a 1979 280z ? Link to comment Share on other sites More sharing options...
blueovalz Posted September 21, 2006 Share Posted September 21, 2006 There are different diameters for the Maxima front rotor. Several years ago I change my old ones out for newer model ones that were about 1/2" larger. The (and this is a guess at the current time) latest rotors I have on the car are 2000 year rotors, and they are roughly 11" in diameter (I could provide exact data later when I get back home). Pictures are worth a thousand words, and would help us solve your problem. Link to comment Share on other sites More sharing options...
stagefumer11 Posted September 22, 2006 Share Posted September 22, 2006 Ok... intresting. whats the possibilty of some pictures ? Mostly im requiring this to see what its like on a 79 280z. It could be a problem that im using the earlyer s12+8 calipers. Which are usually only used on the solid rotor. Since mine are the venter rotor version (20mm nomanal thickness) Does that change the whole subject for me ? Link to comment Share on other sites More sharing options...
blueovalz Posted September 22, 2006 Share Posted September 22, 2006 I'm having difficulty in understanding this issue, but are you saying you are attempting to use the narrower caliper (for non-vented rotors) on a wider vented rotor? Link to comment Share on other sites More sharing options...
stagefumer11 Posted September 22, 2006 Share Posted September 22, 2006 Sorry... hahah i always have a weird way of explaining things. Im using the s12+8 calipers but the vented rotor version. from a 88 hilux, They use a 20-22mm vented rotor. Link to comment Share on other sites More sharing options...
ZROSSA Posted September 23, 2006 Share Posted September 23, 2006 My 1979 z was a zx ie. a s130 not an s30. Could this be part of your issuie? Douglas Link to comment Share on other sites More sharing options...
stagefumer11 Posted September 24, 2006 Share Posted September 24, 2006 Mine is a s130 luckly. Either way ive come accros another way to do this. 5x114 trailer hubs.. I can get them thru work cheep. Everything is the same dimensions on them bearing placement. The bearings are the same ect. just 5x114. So ill be modding them to fot the maxima rotor on the back face. Link to comment Share on other sites More sharing options...
ShinyRedZ Posted October 10, 2006 Share Posted October 10, 2006 What would the thickness of the spacers be, for the vented front disk setup? Link to comment Share on other sites More sharing options...
rosemary 280z Posted October 13, 2006 Share Posted October 13, 2006 Thanx for the very useful information. Link to comment Share on other sites More sharing options...
Calico Posted November 21, 2006 Share Posted November 21, 2006 yeah this is a great one...a wealth of info Link to comment Share on other sites More sharing options...
ShiroZ Posted December 5, 2006 Share Posted December 5, 2006 I completed my S12W front brake upgrade recently. It took awhile to rebend the hardline. Hopefully this picture will help Onto the rear next! Link to comment Share on other sites More sharing options...
rreford Posted January 11, 2007 Share Posted January 11, 2007 anyone try grinding the caliper to make it fit? i put S12+8 calipers on my 240 - 280 hubs, JSK spacer. all fits well, but none of the wheels i own fit - '83 ZX non-turbo (six-spoke), Panasport 14", '81 ZXT snowflakes (15"). Snowflakes come closest, but vertical ridge on the outer face of the S12+8 seems to be the interference issue. Thoughts? Link to comment Share on other sites More sharing options...
joe d. Posted January 11, 2007 Share Posted January 11, 2007 thats what i did and it works perfect. (grinding the caliper) Link to comment Share on other sites More sharing options...
alexideways Posted January 30, 2007 Share Posted January 30, 2007 thats what i did and it works perfect. (grinding the caliper) Any pictures of that????? ------------------------------------------------------------------------------------------------------------------------------------- You can also use a version of the S12+8 calipers for the vented rotor conversion. Let me explain. There are two different Toyota 4x4 calipers with the casting mark "S12+8". One for a solid rotor and one for a vented (wider) rotor. The 1979-85 4x4 calipers are for use with a solid rotor but the 1986-88 4x4 calipers are also marked "S12+8" but they are designed to fit the wider, vented rotor. ------------------------------------------------------------------------------------------------------------------------------------- After searching the J/Y for brake parts I came up with this list. S12+8 calipers donor list: 1- 86-88 4WD PICK-UP 2- 86-89 4Runner 3- 79-90 Landcruiser. Hope it helps. Link to comment Share on other sites More sharing options...
joe d. Posted January 30, 2007 Share Posted January 30, 2007 sure do! i'll get them up in a bit. Link to comment Share on other sites More sharing options...
bjhines Posted February 18, 2007 Share Posted February 18, 2007 ok.. I just went to the JY yesterday... I went to the trouble to jack up half a dozen cars.. In the mud.. in the cold weather... You guys should thank me... An overview... Top Left: late Maxima caliper. . . . Top Right: early Maxima caliper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Bottom Left: 82 280ZX caliper. . . . Bottom right: 240SX caliper Early '82 Maxima: rear calipers could not get rear brackets(welded on) and the wagon model had drum brakes Caliper is the same as the late 280ZX but it has a smaller piston Later '86 Maxima: Rear calipers Flat brackets 240SX: rear calipers could not get brackets... they were welded like the early Maximas' 280ZX: rear calipers Rotors 300ZX: rear brakes were already stripped Probably the same as the Late Maxima calipers 200SX: rear brakes were already stripped ??????????????????????????????? Some differences I noticed right off the bat are... 1. The mounting hangers have different offsets where they bolt to the bracket. 2. The E-brake hangars vary WIDELY!!!! 3. The piston sizes are different. To mention some similarities... 1. The ZX and the Maximas appear to use the same caliper offset, distance from rotor, E-brake hangars, and radial spacing... EXCEPT the Maximas have SMALLER pistons than the ZX models... 2. The pistons appear to come in 2 sizes... A. The smaller pistons appear in: Maximas, 240SXs, I'll bet 200sx as well B. The larger pistons appear ONLY in the ZX models... I do not have the 300ZX calipers to compare... But I am willing to bet they are the same as the 85-88 Maxima calipers EXCEPT they have bigger pistons... If you are wondering why all the research.... I realize that Ross at MM may have the best option available... But I wanted to break this down for everyone who was wondering how the various options boil down.... 1. Early 280ZX rear brakes: The bottom of the line upgrade was always the EARLY 280ZX calipers and rotors... The calipers are heavy, and interfere with some wheels The rotors are small, The pads are tiny. 2. Later 280ZX rear brakes: This is a step up in performance with a few problems.. Large piston calipers The rotors are small The pads are the same as all the later model cars The E-brake cable is a tight fit This uses the early maxima offset bracket(bolt on) 3. 200SX rear calipers with 280ZX OR 300zx rotors This was an interesting option giving some leverage for adjusting brake bias with rotor size... except we dont know some of the details yet... This option could equal the Ross/MM 240sx conversion in funtionality.. But to equal Ross's set up you would need to source 2 sets of calipers and you must have the outer DIA. of the large rotor reduced a fraciton of an inch... The rotors are small but can be enlarged with 300ZX caliper hangers smaller piston caliper common pads The Ebrake connection works well This uses the LATE model/FLAT Maxima brackets(they must be milled for proper spacing) 4. 85-88 Maxima calipers brackets and 300zx rotors This is the option I am working on. It has similar specs to the MM upgrade... You will need to source 2 sets of calipers Large 11.4" dia. disk(must be reduced to 11.22") Later Maxima caliper hanger 240SX caliper body Late model/Flat maxima strut bracket(must have 0.2" milled off opposing sides for proper spacing) 5. Ross' Modern Motorsports 240SX calipers and custom bracket is a full package deal that uses the full dia. of the 84 300ZX disk... this is a well thought out system... It has the right balance of features to make it a very well thought out conversion.... *********************************************************************************************** Here are the details on the 4 lug rotors available for the various nissan cars... Brembo 25110 early 280ZX Rear 10.6" disk Type: Solid Disc Overall Diameter: 269mm Minimum Thickness: 8.6mm Overall Height: 68.5mm Fits: 1981 NISSAN 810 Excludes Wagon 1980 - 6/1981 NISSAN 200 SX 1979 - 1981 NISSAN 240Z / 260Z / 280Z / 280ZX 280ZX w/ Rear Disc ************************************************************************** Brembo 25111 later 280ZX rear 10.15" disk Type: Solid Disc Overall Diameter: 258mm Minimum Thickness: 9mm Overall Height: 47mm Fits: 7/1981 - 9/1983 NISSAN 200 SX 10/1983 - 10/1984 NISSAN 200 SX w/ Rear Disc 11/1984 - 4/1986 NISSAN 200 SX 5/1986 - 4/1987 NISSAN 200 SX 4 Cylinder 5/1987 - 1988 NISSAN 200 SX 4 Cylinder 1982 - 1983 NISSAN 240Z / 260Z / 280Z / 280ZX 280ZX w/ Rear Disc 1981 - 6/1984 NISSAN MAXIMA SEDAN ************************************************************************* Brembo 25125 Maxima rear 11.22" disk Type: Solid Disc Overall Diameter: 285mm Minimum Thickness: 8.6mm Overall Height: 74mm Fits: 7/1984 - 7/1985 NISSAN MAXIMA SEDAN 7/1984 - 7/1985 NISSAN MAXIMA WAGON ************************************************************************* 4-lug Brembo 25139 300ZX 4 lug rear 11.42" disk Type: Solid Disc Overall Diameter: 290mm Minimum Thickness: 9mm Overall Height: 47mm Fits: 1984 - 8/1985 NISSAN 300 ZX (Excluding Turbo) ****************************************************************** Ill complete this later... Link to comment Share on other sites More sharing options...
Recommended Posts