Ben280

Now that you mention the car, I do remember seeing photos in another thread here! I'll have to file your username away as one of the good ones I think a setup similar to mine (3.90 R200 from a 280z, S13 Kaaz 1.5 way and Wolf Creek CV's) will be good to get rolling and have the benefits of a LSD right out of the gate. Chromoly stub axles like @JMortensen mentioned will be a good upgrade, but not IMO strictly necessary for your first round of mods. The Subaru conversion has it's fans, but with how easy it is to find R200/S13 parts I think it's overrated.

Seattlejester makes a solid point about tires. I've broken u-joints in the factory shafts at 230ft-lbs on big ol sticky tires. Drag launches and clutch kicks are what break diff parts, so as long as you stay away from that, and lower than your 450ft lbs, the smaller diffs will be fine. 8.8/9.0 Ford diffs and R230's all require some level of fabrication to fit. The easy move here is to keep/get a R200 rear end, and put a LSD build for a s13 open diff in, and then buy the Wolf Creek CV's. That's my setup, and it's held up amazingly well. With this option, you don't have to source the Subaru to Datsun adapter stub shafts, or the increasingly annoying to find Subaru R180's. There are a couple threads on here about using the OBX helical diffs if you want a real cheap solution, but you can also just leave the factory diff alone, and add in a LSD later if you aren't sure you want one now. Some more info about your goals would be instructive here and we could give you a better answer!

It really depends on what you plan to do with the car. If you want to cruise around, enjoy some spirited back roads and don't want to break the bank, the R180 is probably the better of the two options. The factory stuff will work just fine unless you've swapped the motor. If you have a R200 now, you could just swap in a new LSD center section, do the Wolf Creek axles and have a pretty reasonable setup.

Unless you're doing track/road race with a lot of weight or HP, 6 piston/13" rotors are way overkill, doubly so if you still have drum rears. 6 piston fronts usually allow for more pad area, more even pad wear and provide the proper balance for a 4 piston rear caliper. A 13" rotor will give you marginally better stopping torque, but also dramatically increases the price of the rotors you'll be replacing. Without knowing which of the FSL4R calipers T3 is selling in this kit, it's premature to assume you'd need a prop valve. The smallest size Wilwood caliper would be about in line and allow the factory fronts to be used. Factory front piston area is ~3.1in^2, and the smallest FSL4R is 1.98in^2. A bit rear biased, but if you factor in the pressure drop by leaving all the stock drum plumbing in, they probably are a reasonable match. As @grannyknot said, you want to make sure you consider the entirety of the brake system. Just replacing the drum rears will result in a thoroughly sub optimal brake system.

Those little yellow labels mean somethin' serious is goin down! Looks great, always impressed by the quality of this build.

That's just what the Actor, Mark Rolston would say.....

Have you considered using a Krontec or similar style quick release with a connector in the center for steering wheel controls? I've got a nice curly cord on mine, and it's *fine* but I find it's often an annoying tether for my steering wheel.

https://www.blocklayer.com/rpm-gear.aspx This calculator is pretty helpful for getting the information you want. You'll need the ratio of the gears, the final drive in the car and the overall tire diameter. You can see where each gear redlines and where when you shift where the RPM's drop down to. In this chart, it seems to show the max speed of each gear, so to go from 2-6, you'd be redlining 2nd gear to get into 6th and not bog the motor. Since these are all factory gear boxes, the ratios will all feel about right. Biggest variance will likely be what rear end gear you go with. I'd go with whatever transmission is easier to source and install.

A 3 point belt is designed to allow you to move forward and then "catches" you. This same motion in a 4-6pt harness can result in a basal skull fracture, which is why race car drivers use a head and neck restraint device. 3 point belts also don't keep you in a fully upright position in a roll over, they'll let you slouch or submarine a little bit as the car deforms. A 5-6pt will hold you bolt upright, and then you'll be a couple inches shorter if the roof caves in. You are right tho, if you're rolling the car and hoping the seatbelt is gonna save you, bigger problems! I always thought it was a good "visual" of the restricted motion that comes with a racing harness compared to factory 3 points! Seatbelts in general are designed as part of a system, and a 3 point is designed with the safety system of the stock car in mind. 4 points in my opinion are worthless, and 5-6 points need to be used in conjunction with a helmet, head and neck restraint and roll cage, otherwise they will do more harm than good. I'd see if you can extend the latch so it sits inside the seat, then you'll just need to detach the low mount on the drivers side and pass that through the seat! Should be all set at that point.

If you slot the sides of the seat, just pass the factory belt through those new holes. A 4/5 point isn't really suitable for street use, they are designed as part of a system to hold you in a fixed position, and not rattle around the inside of a roll cage. If the car rolls and doesn't have a roll cage, you're held firmly in the seat while the roof comes in on you. Plenty of people run 4-5 points on the street, but if you have the option to not do that, stick with what you have!

Back to the DTC-30's this weekend and I was happy again. MUCH more affirmative brake feel compared to the HPS pad. A little brake drag on the way to the line and they were good to go. Got some more big upgrades planned, so doing some brake temp paint/strips is a good plan. This weekend was the SCCA National Tour stop at Packwood. Probably the last major event I'll go to this year, which is a real disappointment as we were planning to make a few trips to California, as well as Lincoln for the big show. Oh well. Car did well, by Sunday I had knocked off most of the rust from sitting around all year and a few of the bad habits learned at the track. Saturday was a mess and my mental state meant wasn't up to par, so I finished down in 6th for the weekend. Hope y'all enjoy this video from Sunday!

My DTC-30's for AX duty needed a little bit of dragging to feel inspiring in the first corner. But a lightweight car doesn't make warmup easy. Was looking at the PFC stuff the other day, good data point! Squeal isn't a worry for me, but it's good info for comparing manufacturer language against.

Sounds about perfect for what I'm after. The DTC's are ok, but wear like junk and are about as abrasive as 60 grit sandpaper. I've got Wilwood calipers front and rear, so a fairly common pad shape. Might look to upgrade as I start adding aero since I'm using rather small calipers. Only reason to upgrade there would be a thicker rotor, but I'm using a 12x.81" rotor up front. Rears are rather thin and after their visit to the track turned mostly blue haha!

I figure if I can get the car to feel really nice for 2-3 hot laps in a row, that's about all I need for a time trial type event. There's a fine line for me between going fast and burning the car down during a 20 minute session. I've tried Hawk Blacks, and they were pretty good, but I like the bite and modularity of the DTC-30s more. I might try the DTC-60's but I've also heard that Hawk has been left in the dust technology wise by other companies at this point, and the torque their pad compounds can put out just are nowhere near what other tech can do. Need to research this more, but I've heard enough to be interested. I'll note too that the Hawk Black brake dust is about the most corrosive thing I've ever seen. Don't even think about getting it wet or it will permanently bond and etch into aluminum.

Just cooked the pads and got some serious heat into the system. No brake cooling to speak of, which with wheels this small and wide is a real problem. The pedal felt alright, but the brake feel just didn't instill the confidence I wanted. I need to do some research and probably some testing to find something that I like. Water and Oil temps were a bigger problem, I could get about 3 hot laps before temps were too high.

Getting back to racing, and had a couple of events already. First up was SCCA Time Trials National Tour at The Ridge Motorsports Park up in Shelton Washington. First time at that track, and first time on track in about 6 years, so I wasn't about to light the world on fire, but I managed to go sub 2 minutes, which was the goal for the weekend. I did swap out my lightweight autox front hub arrangement (T3 aluminum hubs, custom hats and scalloped rotors) in favor of a full vented rotor and OEM steel hubs. Figured additional thermal mass would be good, and I was right. Still need to work on brake cooling, and cooling in general for future events. My auto-x gearing meant that I was on the limiter in 4th for a good chunk on the front straight. When I go back, I'll likely swap out some of the trans gears to try and optimize those ratios. Anyway, video here: This past weekend was back to Auto-x, so I swapped out the front hubs, swapped back the brake compounds, replaced a corded front tire, and went racin! I was using the usual Hawk DTC-30 on the track, but have been messing around with the Hawk HP+ pads for auto-x, hoping for a bit less need for warm-up. Well the HP+ suck, and I'm throwing them in the garbage tomorrow! Just really numb, bad release, and no real initial bite. It was also fairly cold, and my tires were having issues getting up to temp, I've been really thinking about switching up a couple things in the car after August, so wheels and tires might make the list. Anyway, best time from Sunday, when we finally got the tire to be over ambient temp! Reasonable time, but should have been 3 seconds or so faster on this course. Always more work to do!

I feel like these wild mish-mash collections of parts are from people looking to convenience over a proper engineered solution. Brakes need to be viewed as a cohesive F-R system, I'm surprised that more companies haven't taken the example from Z car garage (and really everyone else) and offers a full brake system. It's not witchcraft, unless you're trying to use maxima rear brackets and stuff you can find at pick n pull Lots of talk here lately about a need for documentation. Is this a new concern? I feel like nobody has offered it really in the past 10 years, so what's spurring this now?

Makes sense now, I was trying to imagine how this would work with the factory rear uprights! Watch your roll center as 260DET said, you can easily get into trouble and the car will behave terribly. Since you're already welding in camber plates, good enough time to add some reinforcement up there, although I think if you try and get too vertical, you'll start hitting your springs on the inside of the shock towers.

Thanks for posting! Cool to see some of the principles of intake tuning in action, namely, longer runners pushing the powerband lower at the expense of total HP, the 205mm had the earliest power spike with a lower overall number! Good stuff to keep in mind when looking at intakes for triple carbs and ITB's!

Just when I thought this build couldn't get any cooler, you throw Motec and a dang HGT box at it!?

Cool! For some reason I thought you got a 550. Should make it easy for troubleshooting!

@DuffyMahoneyHow are your injectors wired into the ECU? If i'm not mistaken there are only 4 injector drivers on the haltech board. Are you running 2 batches of 3 injectors? I seem to remember from a few pages back you got a CAS dizzy piece so you'd have a cam signal heading to the ECU for a more sequential system.

Haltech's are a bit different than the MS3 I use, but the injector timing sounds to be fairly out of joint from Duffy's video. If the crank sensor is bad, inconsistent or just something the computer can't figure out, the MS would either not start, or show errors in the Sync gauge. I doubt the Haltech would try an muddle through a bad cranking trigger. I the trigger and home wires are also shielded bundles in the Haltech wiring harness, so unless Duffy isn't using those, noise shouldn't be an issue either. Injectors are behaving badly at a minimum, I'm interested to hear what the report on them is!

It sounds to me like Madkaw has a prop valve installed in the rear circuit, and has it dialed all the way down. You can only "bias" a dual master cylinder system, otherwise you are proportioning the amount of force to the rear. This would be mostly in line with what OP had to do. Would be helpful to know the model Wilwoods you are using, as saying you are running Wilwoods all around is just like saying "I run calipers all around". If you know the MC size and the size of your pistons in the caliper, you can do some pretty simple math to tell you where you should be, and how much prop valve you need to throw at it.

That sounds to me like a few injectors are just going fully open above 1300rpm. I'll be interested to hear what the injector lab place says about them. Were you logging data on the ECU? Should be reasonably easy to see if you had trigger errors or a bad sensor. Good thing to check, but I don't think it's the root cause of your issue here. Another thing would be to try installing a dummy injector and see if you can run through the test modes on the ECU to confirm the ECU is at least sending a good command.