bjhines

Carbotech USA makes (has) pads to fit the early Toyota truck calipers... http://www.carbotecheng.com/prod-ct-compounds.htm toll free (877)-899-5024 Call them to order yours... specify make and year of your calipers... for the non vented pads... 1984 Toyota Four Runner would be the application. I have used their Panther Plus and XP9 compounds... they work very well but you will boil fluid and crack rotors if you drive it to it's fade point with race pads... I strongly suggest you add brake ducts... ...

Carbotech USA makes (has) pads to fit the early Toyota truck calipers... http://www.carbotecheng.com/prod-ct-compounds.htm toll free (877)-899-5024 Call them to order yours... specify make and year of your calipers... for the non vented pads... 1984 Toyota Four Runner would be the application. I have used their Panther Plus and XP9 compounds... they work very well but you will boil fluid and crack rotors if you drive it to it's fade point with race pads... I strongly suggest you add brake ducts... ...

are those overall backing plate measurements??? because it appears that the 300ZX has more actual pad area... 300ZX on left.. stock Toyota on right... Both are the same brand from Autozone. Here is a comparison of 2 different Toyota pads for the same vented caliper... The one on the left is Hawk HP+ for the Toyota application... The one on the right is off the shelf street from Autozone... I do have to trim the stock Toyota application pads to clear strut mount tabs on the inboard positions... As you can see... the Toyota race pad on the left has a smaller overall height than the untrimmed stock Toyota pad on the right... All of the pads have the same overall width and pin spacing.. this must be the same in order for them to work... I have had to file the edges of stock Toyota application pads in the past.. the paint and sheared lip made them too wide to fit easily.... You can see in the picture above that the race pads have more friction material than the Autozone pads... and the race pads place the material lower on the backing plate than the stock pads... It seems to me that you will get quite a bit a variation from one manufacturer to the next... disclaimer... some of the edge clearances in these pics are misleading.. the pictures are not always directly overhead... The comparison between the Hawk pads and the Autozone pads is accurate along the bottom edge...

I have used stock 240Z brake calipers, Non vented Toyota calipers, Toyota Vented calipers w/ 84 300ZX rotors and spacers, and I am building a car that will have Willwoods installed. A little information on Race pad sizes and availability..... The stock 240Z calipers have a number of different options available for RACE brake pads.... I need not mention them all.... The early Toyota NON-vented type, bolt on calipers use a slightly SMALLER PAD than the later Toyota vented caliper set ups. There are several manufacturers of performance pads that fit the EARLY NON VENTED calipers... though they are not always in stock... Here is a comparison between the early VS late Toyota pad sizes... they are not interchangable... The later VENTED Toyota claipers work with the first year 1984 300ZX 4-lug rotors and a spacer... I had a little trouble finding readily available race pads for this set up... there are quite a few choices out there but they are rarely stocked... You can use the 1991-1996 300ZX pads in these S12W calipers... I actually think they fit better than the Toyota truck pads.... they also appear to have a little larger friction surface.... and the 300ZX pads use more of the outer edge of the rotor than the truck pads.. the truck pads leave 3/8" outer rotor edge untouched Here is a comparison between the 300ZX pad on the left and the Vented Toyota pad on the right... both of these pads will require a tiny amount of trimming in the areas near the wear squealer tabs... Here is a shot of the 300ZX pads with the squealer removed and the corners notched to allow fitment of the trimmed pad on the inboard side of the caliper... I know that the squealers usually mount on the outbaord side of the caliper... but in this situation the middle tab has clearance on the inboard side only... this arrangement involved the least trimming for fit... ...

I am getting major headway on my new project chassis right now... I have been dealing with exactly the same issues... though not nearly as bad... I was able to drive the car for some time before I tore it down.... The car is vitually rust free(even after tear down). It had numerous alignment problems though... I had been able to adjust it through the use of offest camber bushings... but I intended to build a straight track car with this chassis... So I sent it off to a reputable road race car builder frame shop. They did a fantastic job getting it straight... but I was told that there is still some misalignment in the chassis that the technician swore was built into it... the car shows no signs of ANY major collision repair... He pointed out some odd spot welding and original panel misalignment.... Try a different front crossmember... they can be usually be found locally through Z-clubs... It is not uncommon to find the holes that bolt it to the chassis are elongated one way or another... It would not surprise me if the crossmember rack-mount-tabs are not square... Nissan made improvements in the crossmember design in later years(260 and up?)...

The new design Dave has come up with looks like it allows height change without changing strut travel... that is a VERY NICE set up there Dave...

Here is what you get with camber plates or stock mounts that distort the top of the spring... I have a brand new pair of these EMI plates and I think I am going to stick with them for now... I like the idea that they are strong.. but I dislike the distortion of the spring they will cause... The Airizona Z car set up is what I wish I had to work with... I will be spending some money on his stuff.. I fully trust his design.. and it keeps the spring inline.... There are hydraulic swing plates available that fit between the tophat and the top of the spring... but I think they are for 2.25" springs.. not the 2.5" we use...

About those Hoosier failures... These were beaten hard in rental cars and failed quite spectacularly.....My understanding is that too little camber combined with too much heat is what causes this... I would not put Hoosier to blame on this failure.. they are race tires... they grip like hell.. and they can overheat and go to pieces... these tires were run in a 6 hour enduro.. the drivers and crew took a chance and lost.... I balanced his tires and a bunch of others at Sebring during the Jan06 PBOC winterfest.... ME at the balancer.... I really needed sunglasses.... Money shot...

ohh I almost forgot to post a pressure range... I am shooting for 34 PSI HOT... I usually start at 28-30... this is currently on 225/50/15 Victoracers... I have had similar results with Toyo RA1s.

I have done autocross for a few years.... I primarily run in HPDE and time trial events though... I have been using pressure rise and wear patterns to determine correct pressure through tire inspection... too little negative camber and poor lateral stability can mislead you when looking at tire wear to determine pressure.... I know that many instructors at autocrosses will tell you that you should start high and work your way down.... I have been told 40PSI for stock sizes on most daily driver cars... I think that is a little high for best grip... I would try marking the edges with a white shoepolish stick(grocery store). Mark the transition from the tread to the sidewall... check the amount of rollover after each run... you want to use all of the tread without getting contact on the sidewall... this varies with different tires and profiles.. so you still have to adjust for feel... Some tires just don't behave.... getting good turn in may be impossible with some of the cheaper high profile street tires. Falken Azenis are a good choice if you intend to drive on the same tires you autocross on... but I would rely on another vehicle on rainy days... Hoosier makes some of the stickiest tires available for less than $200 each. They also have a super sticky autocross specific compound. You don't want to even think about running those tires on the street... I am not sure that the affordable IR temp guns are going to give very good results in an autocross situation... but I have never tried it... I have heard of people getting Azenis so hot during autocrosses that they get "greasy" feeling.. I have a little trouble believing that because I have run Azenis in 90* heat on track for 30 minutes at a time... you can overheat ANY tire on track... and yes they have more limitations than the Toyo RA1s or the S04s or the Victoracers... but I do not think you are going to overheat any tires during an autocross session unless you go around pushing madly around corners.. slower in>> faster out and UNWIND THE WHEEL.... that should fix any overheating problems during an autocross.... You might also try aligning the car with a little toe out in the front... just a hair out... it will help in those sweepers.... but it will eat the hell out of your street tires in the long run...

Now that is doing the math...!!!

To give you a good idea on how important this thermal expansion and compressibility can be.... BIG TIRES..like mining trucks and loaders use... are filled with water AND AIR.... they are not really that concerned with thermal characteristics as much as they are concerned with compressibility... A tire that big.. with that much weight on it... is acting as the suspension for that HUGE vehicle.... if the tires were filled using only air.. they would bounce over bumps in the ground like they were toys.... The tires would compress and store HUGE amounts of energy... then they would suddenly release all that energy and spring the heavy equipment right into the air.... Loaders would toss 10 ton rocks like a short order cook flipping pancakes... There is a very limited amount of damping that can be expected from a large tire like that.... the air filled tires act like an undamped spring.... The trick is to fill most of the tire with an incompressible liquid... water or oil.... then the rest of the space is filled with air... the smaller airspace does not store nearly as much energy.. the internal damping characteristics of the tire can more easily deal with the stored energy potential of the smaller airspace.... finer points of this design include ways to baffle or partition off the inside of the tires to keep the water from sloshing violently in the huge tires...

THere are more considerations than weight/density of gases... Helium vs AIR mixture has little in the way of weight savings... I have not done the math... but it will be measured in grams for all 4 tires together... take a big crap right before you get in your car... you will have unloaded 2 orders of magnitude more weight in the bathroom... Thermal expansion and compressibility are the main considerations... CO2 and propane are highly compressible gasses... this is why they are soooooo popular with manufacturers of aerosol cans... they are not soo good in tires... one tends to be a fire hazard when mixed with oxygen and the other(CO2) changes pressure too much as temperature changes... Nitrogen... which is most of the air in which we live.... is not quite as compressible as other common, SAFE gases... it takes a relatively large pressure change to alter the density of nitrogen gas... With a little high school physics(GAS LAW) you will understand why a tire filled with nitrogen will not undergo as drastic a pressure change as airmixture filled tires when they get HOT... You cannot alter things very much by using pure nitrogen... it is mostly what we breathe anyway... if you do go that route you will need to come up with a way to purge other unwanted gasses from the wheel and tire assembly...... usually 2 diametrically opposed valve stems... one as a purge and the other as a fill... Helium WILL NOT LEAK out of your tires the way it passes through a thin rubber membrane(balloon)... It will stay in there as well as any other gas that does not dissolve the casing of the tire...

as long as you use keep the edge profile height (thickness) of the door intact.. you will have a sturdy door.. some of the early 240Z doors had no side impact bar... you can remove the bar without causing any problems... except less crash protection...

I you could richen it up around 3kRPM and lean it out past 5500RPM it would look even better... You might post a little higher HP too....

Nice work.... I tend to cut aluminum with an agressive wood blade in a jig saw....

ohh... I just realized what you are talking about with the lower /-- bar... That is actually a first attempt at the roof bar.. but I forgot I shoved it back there when I got into the car( it does look like it was bent to fit though it does not reach the corners)..... the lower bar is not part of the design at all..... I made a much prettier roof line bar and tossed that /--- into the scrap bin.....

I purchased a nibbler and a flanging tool from Northern Tools/HF... I use a grinder and hand snips for details I can't get into with the nibbler.... A good set of Greenlee style punches is also great to have on hand... I purchased a set of flanged lip dies as well....

A consideration popped into mind... The fuel pump may need a lot of bypass flow to stay cool enough...

in general regulators respond faster/better if you minimize "ballooning" in the lines on the regulated side... this usually means moving it as close to the injectors as possible... and using hard lines for as much as possible... The return might only be used in this case to damp out oscillations in regulated pressure..... there are other benefits to return lines.. but this sounds like it is primarily used as a sort of fuel pressure damper... This assumes your problem is due to a slow responding regulator... It is hard to tell form the description if the regulator is simply bypassing extra fuel or if it is just a calibrated bleed.... In most cases the regulator is in series(inline) with the supply line... If yours is actually parallel(tee'd)... then it must be dumping a fairly large amount of fuel through the return line most of the time... I can't see this as really needing any change in location of the regulator.. because the length of regulated fuel supply line would be the same no matter where you place a regulator if it simply tees off the line(parallel).. in other words... the whole idea of moving it closer to the engine is to minimize ballooning of the lines... but a Tee'd connection will allow the entire length from tank to injectors to balloon and affect the regulated pressure... Check the science behind this fix...It may simply be an easier(accessable) relocation of the regulator... the whole fix may simply be due to a more robust regulator design.. The return line may have less of an impact than simply allowing relocation of the regulator...

I had to roll my rear upper lips... You can rent or borrow a fender rolling tool that will get fantastic results... It bolts to the hub flange and has a plastic roller that rotates on the hub while applying pressure to the lip at an adjustable angle... it does very smooth work.... I have 15 x 7 with +4 offset Hyashi wheels... with 225/50/15 Kumho Victoracers... I have also mounted Toyo RA1s on these with similar results... I have also installed offset bushings to push the wheels outward for more negative camber.... the strut towers have been slotted enough to get equal camber on both sides... I also have the rear wheels pushed slightly forward because of rear toe in...

about Tony D.... YES.. bitter would be the word...I spent a GREAT DEAL of time defending myself against him in those posts about header weights.. he is abusive first.. AND lying to boot.. and completely unwilling to engage in the world of reasonable discussion... just read the posts... Any mention of Tony D. throws up red flags in my book... I will try to refrain from mentioning him.. in any case... everything I posted about blow through Webers in this thread is fully supported by all sources... it is no longer the only way.. or the best way to get high performance....

Just click on my nametag... previous posts... with pics... I have had terrible experience with T.D.... http://www.zcar.com/forums/read.php?f=1&i=642371&t=642284#reply_642371 This went on and on in these threads as well.... http://www.zcar.com/forums/read.php?f=1&i=643552&t=643552#reply_643552 until T.D. finally went off the deep end with assinine claims about how there is no scale in the world that reads the same weights... http://www.zcar.com/forums/read.php?f=1&i=644604&t=644307#reply_644604

I never said it would not work... I simply stated it was unreliable and a poor performer compared to the same engine with a computerized system... It is kind of like builing an airplane out of wood and cloth... It definitely WORKS... but it is outdated now that we have much better technology... Any attempt to use a blow through Weber Turbo set up is an exercise in nostalgia.. not performance...

lol... Tony D.... well I have caught him up to his eyes in bull#*** before.... Gimme a break... saying that it exists... that is fine... but I guarantee it doesn't work well at all... there is simply no way it would turn the kind of numbers that a fuel injected car will turn with ANY RELIABILITY.... Tony D... lol.... I can provide some linkys to a recent...VERY EMBARASSING THREAD... lol....