johnc

This setup didn't work. Huge aero understeer at speed - almost drove off the track on the second lap. A splitter needs to be no more then 2" off the ground if you want it to work as a splitter. You can alway angle the splitter down and just have it work as a spoiler. (The car looks like its about 6" off the ground but there's a jack under the car behind the door)

Given the amount of work involved it might be better to just build the turbo manifold from scratch. The L6 port spacing and its positioning on the left side of the engine is pretty unique.

I would prefer to go with the Z32 trans because its quieter then the earlier Z transmissions. The extra mass also helps dampen driveline vibration and I would also most likely run the Z32 driveshaft (the one with the CV in it) to also reduce driveline vibration. The longer springs tend to improve initial bump compliance. I know its counter intuitive but they react a bit faster then shorter springs with the same rate. I can't explain it but I've seen it on a spring tester. In general I'm not trying to make the lightest S30 when building for reduced NVH and comfort. Toby's front roll bar is mounted in bearings (pillow ball mounts), runs a blade adjustment, and is currently mounted to the front LCAs via rod ends. We have the complete suspension on the E36 modeled in Mitchell and optimized the roll bar mounting so it does only its job with the least interference possible. We also found that BMW really knows their stuff and have tried to mimic a lot of factory geometry on a car that's 4" lower.

Yes. And in testing on the front of Toby's FP E36 BMW, something as simple as Torrington bearings on top and bottom of the 2.5" springs gave better course times and a more consistent feel for the front of the car. From what we can tell it let the spring turn under load. We marked the spring before and after and would see turning displacement with the Torrington bearings in place and none when the bearings were removed.

If I was going to build one, this would be my initial plan: 1975 280Z Chassis - A little stiffer and better corrosion protection then the earlier cars. Single turbo VG30 engine - Tuned to about 300hp. Z32 5 speed. R200 with an OS Giken LSD. 235/45-17 tires on 8" wide rims all around. Custom valved Bilstien shocks. 2.5" race springs 185F 215R - 12" tall. Camber plates - rubber insulated. Hypercoil hydraulic spring perches top and bottom. Mostly rubber bushings. Additional rubber or urethane insulation creating a pesudo rubber isolated subframe. Complete Mazda MX-5 brake system including ABS, computers, MC, booster, wheel speed sensors, etc. Then lots of detail work on interior sound deadening, big rattle elimination effort, new and custom door, window, and hatch sealing, 350Z seats...

An E30 or E36 BMW is not a "modern" sports car. They are 15 to 20+ year old cars. And I'm pretty sure I can build a S30 to be comparable to a non-Z06/non-Z51 C5 Corvette for under $30K.

Maybe we need some clarification on "breaking the bank." If S30 aficionado is willing spending $60K on a new M3 and then complains that you can't get similar world class performance when spending $10K on a S30 then that person is a fool. If you take that same $60K and spend it on a S30 you can get pretty damn close to that M3's level of performance and comfort. One of the keys on reducing the NVH on a S30 is to emulate the concept of a rubber isolated subframe that all modern performance cars have. Isolate the front cross member, TC rod mounts, rear transverse link brakes, front diff cross member, and the strut tops and you've gone a long way to reducing NVH in the car.

I agree, you can't have raw and comfortable. Here's RAW: Here's comfortable:

Dang it! I've been making a mint on eBay selling the rare S30 left control arm. You guys just spoiled that.

The answer is yes. The first 80% (the handling) is known and fairly straight forward. The last 20% (the comfort and NVH) will take the most time and effort and the attention to detail is critical. Rick Johnson has achieved a modern level of handling, comfort, and NVH control in his V8 240Z but it has taken him a long time. He is (was) a NVH engineer for Nissan and did a talk at my shop on how to isolate NVH by determining the frequency. He went so far as to rebuilt and sort out three different R200 diffs trying to reduce as much gear noise as possible. I did something slightly similar to my last street 240Z and a whole lot of little things went a long way to making the car more comfortable. Like rebuilding the window regulators and using softer durometer rollers and Teflon guides sourced from McMaster-Carr.

The Tokico Illuminas probably have too much compression damping and will work the tires hard. It will be important to run them as soft as possible while still having enough rebound control.

I agree 100% that flywheel weight is critical to a good launch. After that, you want to shed as much flywheel weight as possible, but that's not allowed for safety reasons.

What shocks?

225/50-14. Hankook Ventus Z214, Hoosier A6/R6, and Kumho V710. All will work on your 14 x 7 rims and will give pretty good (not great) traction at 300hp if you have a good LSD and good shocks. Lots of Vintage road race S30 guys have run those tires in that size with 250 to 300hp.

I agree but that has nothing to do with the flywheel and everything to do with gearing. When you go into the next gear, the rpm you start off at is determined by the drive tire OD, final drive gear, and transmission gear. The only way to pick up the extra 300 rpm in your example above is to spin the tires, slip the clutch, or shift at 6100 rpm.

As Ricky Ricardo would say, "'splain please." How can spending more time in the 3,000 to 6,000 rpm band through 4 gears (as an example) lead to quicker 1/4 mile times? Let's say you spend a tenth more time on that rpm band each time, doesn't that mean its taken .4 longer overall to cover the 1/4 mile? Wouldn't this especially true for a manual transmisison car?

I watch the driver, especially if they have some talent like Randy. I watch the hands, body position, where they look, etc. and listen to their comments (if any). You can tell a lot about the car by looking at how the driver has to drive it. On some of the car crash videos on YouTube you can see the crash starting with the driver inputs long before the car starts getting out of shape. I do the same when instructing - I tend to watch the student as much as I watch the road.

WTF is up with the steering wheel? Did he use the same wheel in both cars?

Craftsman is lying. I know of no 1/2" drive impact gun that will generate 750 ft. lbs. forward much less reverse. You need at least a 3/4" drive gun to get near that torque number. If you check the "working torque number" (the actual torque the gun puts out) you'll find your gun is in the 300 ft. lb. range. I have that exact gun in my shop.

Yes, but the change is very small with 1/2 coil cut (less then 5%).

190 rwhp 180 ft-lbs torque.

One important question is to ask how fast they spin the driveshaft to balance it. That adds to the cost. You do this because the driveshaft rpm varies based on u-joint angle. So, the transmisison output may be spinning at 3,000 rpm but the actual driveshaft speed varies from 2995.9 to 3004.1 if the shaft is at a 3 degree angle. Getting that balanced right is really important.

Another Mark Ortiz chassis newsletter.

I hope he does well. His battle with Robbie Gordon at Montreal in 2007 was fantastic. How it ended sucked, but its was great racing between the two up until lap 72.

For a vintage legal brake setup the closest to the approved FIA calipers are the Toyota 4 x 4 S12W calipers with a vented front rotors and drum rear brakes. Some vintage groups might let you run a solid rear rotor with a single piston caliper (280ZX/240SX). Shocks can be single adjustable only. Coil over 2.5 ID springs are allowed along with camber plates. Spherical bearing (monoballs) can replace the suspension bushings. Fiberglass hoods and hatches only and no carbon fiber parts. Spoilers are limited to the BREe style parts. Typically wheel widths are limited to 7" wide and you can run 14s or 15s.