Return of an Original Gangsta

[autox320]

I'm buying a few of those filters, my generic one was making me nervous even before reading this. A life spent in the aviation world has basically ruined my ability to just "leave well enough alone"

For sure man, when can't trust your equipment it's aggravating. Out of box failures don't inspire confidence about the auto parts industry. Sure it's just a cheap filter, but by time we've reached this level, the entire source of parts goes into question for me. Luckily there's not many "parts" on this car. Plenty of other things I rant about during the build of this rig.

Understand where your coming from. Race level cars should be thought of in aviation level standards in my opinion when comes to safety and condition. I try to hold a high standard. Saves time which is expensive once at the track.

[Somjuan]

Sounds like time for safety wire everywhere!

[autox320]

Sounds like time for safety wire everywhere!

Nah PITA. I like metal top lock nuts and if need be loctite. Marker paint lines on each area. Can glance from the hood at the front suspension and see if anything is moved or loose. Rear I have to duck my head in the wells to see but all marker painted to view at a glance.

:o)

[WantingAfunE21]

Nah PITA. I like metal top lock nuts and if need be loctite. Marker paint lines on each area. Can glance from the hood at the front suspension and see if anything is moved or loose. Rear I have to duck my head in the wells to see but all marker painted to view at a glance.

:o)

YOu should Check out this stuff, its what is commonly used in aircraft maintenance to both indicate a torquing process has been completed, and that the fastener is still tight during inspections.

[autox320]

Thanks for the reference paint, may try some.



Few more issues. Never ends right

Distributor keeps having oil underneath it. Replaced the o-ring. btw the TEP and IE Tii distributors are new machined billet so they use a standard o-ring and not the factory proprietary one. I know I tried to put a new factory one on it and the groove is machined too narrow. Even with a new o-ring the oil is not from there it's actually the oil coming up the shaft itself for lubrication. There's a small jet hole in the bottom of the distributor cover back of the head where the gear sits inside. The larger drain hole leads to the head. We are using sealant and may try a actual gasket. I've read on the 02faq that the drain hole may be obstructed with sealant. I'm not sure but with an event tomorrow I'll wait to dive into that again.

Another issue has been sputtering just off idle. I've dealt with the fuel and now that it's clean in the bowl fuel adjustments aren't solving it. Finger back to the distributor. When talking with Dad about it I thought maybe the spring that came off once in the beginning of the build came off again. Took back apart to see. Well it didn't come off but the same one was loose so that allows timing to come in super early curve. As in with a light on it was at 30+ degrees off idle lol was starting at 1000 rpm Not cool and needs to be just a tad later, and it was bucking a bit lol yeah now know why.

I redid the spring and made it feel like the opposite one when pushed with finger side tension. I know you can run two different springs and give different curves but this Tii distributor is like an off/on switch. It seems to have initial timing and then all in about 1800-2000rpm. So tightened up and fixed that loose spring to hold the weights in a bit longer making them open together. Timing came all in 36deg @1800-2000rpms. Now could lug the motor a bit and actually have driveability back at low speeds.

Just one of those things with mechanical that have to stay on top of and can see it with a good timing light. Driveability may be able to notice something isn't right.

Back to happy land so loading up for another event. The end all be all fuel filter showed up. Going with a inboard parker Racor filter/water separator. Well known in the marine world. This will replace the stock bosch e30 fuel filter as the main filter before the pumps. Tired of playing around with "factory" style and aftermarket junk.

[autox320]

Represent.

[WantingAfunE21]

I always wanted a sticker that said "bought, then built" then vertically inside the last t it has the word "badly" cut out.

[Somjuan]

I always wanted a sticker that said "bought, then built" then vertically inside the last t it has the word "badly" cut out.

I see your car is just like mine

[autox320]

Tires work great. So much grip had to hookup add some rear bar back in. It's faster with more grip for sure.

Almost unseated a turbo miata for FTD, but was .053sec off placing 2nd overall. Dad was 1.5sec from the miata placing 11th overall.

[autox320]

Installed the Ra"N"cor filter no more bullshit filters. Made a bracket out of 1/8" plate supported by a 3" chunk of 14ga C channel with 2 1/4" rod stays to give 3 points of weld mount. Works great now can see with the separator. Probably won't have to change this filter for 2yrs at a time, but have spares if need be in the track box. Using the torque marker paint Roy suggested on all the suspension points (thanks man).

[autox320]

finally got those three letters in autocross last Sunday; was ahead of the kart by 1/2sec

F T D

[WantingAfunE21]

finally got those three letters in autocross last Sunday; was ahead of the kart by 1/2sec

F T D

No likes on here, so I gave you one on Youtube. Nice run!

[autox320]

No likes on here, so I gave you one on Youtube. Nice run!

Thanks man. It's been a nice return to run with the local club we started with. Some remember the 320 from back then and can't believe it's the SAME one. We like reminding them this old school bimmer can still play. Dad has been having a blast giving it hell like we only dreamed of a few years ago.

[AndronPrime]

I read 10 pages of this thread throughout my lunch break. I am getting so many ideas for setting up my front suspension! Hopefully I can finish my reading when I’m home.

[autox320]

I read 10 pages of this thread throughout my lunch break. I am getting so many ideas for setting up my front suspension! Hopefully I can finish my reading when I’m home.

Glad to help inspire ideas. If need a measurement of something let me know.

[autox320]

I changed plugs from the Iridium's to a set of NGK vpowers (BR9EYA) for our engine heat range. I cut the ground electrode strap back unshrouding the center electrode about .020 and regapped to .030. The car seems to like these best.

Another event down. My dad couldn't make it so convinced my friend Daniel to co-drive with me. He's another hot shoe, and was faster than me by 0.8sec. For autox thats like a mile . I kept telling him he needs to drive this car, and it was his first time behind the wheel. By his 2nd run he was faster than me. He ended up only 0.2sec from FTD behind a new exocet miata. If can even call the exocet a car since its only tubes ie like a aerial atom budget chassis weighing in at 1436 lbs (I asked). Anyways heres our top runs. Daniel definitely stitched together the straight and carousel better. . . damn he was left foot braking; I need to try that

Was a fun event and a lot more interesting tube/caged cars showed up in the mix. Turn out was excellent.



Daniel's run (tidier and cleaner)

[autox320]

Gopro ran out of battery (of course) and missed majority of the runs last Sunday. Placed top of the pack behind a bunch of karts. Daniel was .07sec behind me this time as we fought a "vette kart" and the miata excocet. The vette kart is an interesting tube chassis modeled after a c6 with c6 suspension parts. Then a cobalt turbo engine powertrain making in the 300s hp+torque. Fun machine

Things were going good till the last 4 runs of the day where sounded like an exhaust leak starting. Car was down on power and the exhaust leak was like an open header tube. Went to load on the trailer and saw the cylinder #1 tube broken about mid way. That would do it.

Fixing the header and test to see if leaks. Adding some gussets to prevent the tubes from stress. Thinking the delrin engine mounts had flex probably cracking the tube allowing slight flex. Making all engine and trans mounting solid steel. Engine is out for a minute, but going back in today I hope.

Successful testing of additional suspension modifications, but will post about it later. Right now want to get the car back running and see if fixed the header leak. The setrab oil cooler was ordered. Have other things to attend to before heading for the track.

[autox320]

Whew, making the drivetrain mount solid steel opened a small edible can of worms . The engine mounts were made exact fit so once bolted down it showed how much the trans holes were off being several feet back from that mount point. Had to refine the trans mount and cut reweld the exhaust to make the angle perfect since nothing will move. The delrin setup was deformed and the trans to engine were definitely in a bind. Flex = breakage, so lets see how the solid setup does. The drive shaft just makes it with the trans hanging only about 1" when the engine mounts are bolted. Not any room for error to get the shaft in its home. Added attachment points for the exhaust engine mount and trans making all mounts have two grab points.

Header was fun to weld back up. Gussets with some pieces of 3/16 rod laid in between the tubes where they almost touch. There's 6 places where tubes are close enough to gusset so went for it.

Found the trans clutch fork spring wasn't in the back holes of the trans. Pulled the trans to find the spring dangling in there. Fixed that and made the header to trans brace two pieces that fit like a puzzle.

Went to put the throttle cable aluminum bushing back in and it had play. Come to find out the snap ring has worn the aluminum all to hell . Back to a bushing with plastic insert for now.

Noticed when working on the rear that the spring hats are bowing at the washers mount points that hold the hat in place. More on that later but used some nicer hats that I used on the M3. Welded washers onto the shock and custom fit for these beefier hats.

Putting into track mode now that most of that is sorted. Track brake pads and tires. Setting up for checking cross weights and alignment again.

[autox320]

Almost ready; today was setup day. Now that the fixes and exhaust are back to normal, it was time to rescale and check alignment. Cleaned and verified the carb.

[autox320]

Setrab kit from Ireland Engineering. Super setup when want the best this is definitely it. I was a bit worried on the filter block but it's a nice custom piece. As expected IE have done their homework on this kit. The filter block even has two taps for either temp/pressure monitoring. I've already tapped the housing so not using them. Plan to tape off the front intake air inlet vent front of the car to control temp if need be on super cool days. This should keep temps in my target range of 240-250F on track days even in dead summer heat.

Setup cross weighed and alignment done. Changed oil. All thats left is adj the valves and adj the throttle cable one last time.

[autox320]

Droop / down travel limiting

Ran a droop/down travel experiment after curiosity from the RC crowd.

Something that has bothered me especially in the rear is amount of droop the shocks had. Measured from bottom wheel edge to the fender edge. Front shocks droop on our setup is 1.25 inches. Rear was several several inches to the point when jacking the car after the springs fall out of place travel limited by the axles pulled from the diff . A lot of things at play here like vehicle weight on the corner when let down on the spring, but that counts when measuring droop. If your spring rate is less than the corner weight of the car there will be spring compression as part of droop. The difference from when at rest to the distance the wheel travels to be off the pavement is the droop.

The rear always has been hard to pin down on handling settings, and I keep trying to improve it. Always seemed a bit unpredictable when entering a turn at high speed for the rear end to take a set. Leaving sweeper turns the rear tires fight for traction as well. Most of the time heard from the engine revs meaning a tire or tires were spinning. Stiff springs make it worse, so decided to toy with droop experimenting. Turns out in short it's the droop. Concentrating on the rear since most problematic. Welded a piece of cut square tubing underside of the shock hat on the body (most meat) keeping inline with the shock. A piece of 3/16 welded onto the control arm tube near the hub. Joined with 3/16 winch cable as an adjustable droop limiter with simple cable clamps.

Some believe when the car rolls say around a carousel and the inside tire drooping to touch the pavement is better than nothing for traction. It did provide some traction, but not what you'd think. Experimenting with the droop limiter proves the inside rear spring on such turns was leaving the seat. It has been havoc on the rear spring seats. Its why my rear hats were beaten to death and the inside edge was about to fail. Relying on the shock down travel after leaving the spring isn't much down pressure to keep the tire on the ground once the spring is unloaded.


quote:"think you are rolling two subjects into one with this question. Droop limiting is not the same as having no vertical load on a droop limited wheel. The droop limiter will not cause gravity to turn off; if an inside wheel is off the ground, it is not because of the droop limiter, it is because all of the load has transferred off of that wheel." FSAE forums


Had perfect opportunity for testing last event since three of us driving the car at different times. I was able to work a station inside a high speed carousel corner. Watched every car as it went around seemingly in slow motion I studied all tires to pavement.

Actual testing. Limit strap to control droop. With the cable in place I started with 1.25" of available rear droop matching the front. This happened to be just keeping the rear springs in their seats when lifting the car. Same carousel turn the inside wheel would now just barely leave the pavement. Could see and hear (engine) the inside rear tire spinning as no traction was available. It felt more confident to enter at higher speeds but still had some wheel spin from that tire unloading. Right away you'd think the limiter is the cause(refer to quote above again), but it's actually the load has been transferred off the wheel. With the shock drooping so far before just couldn't see it easily. Further proving this to myself, during lunch break took away another 1/2" of droop making it 3/4" in the rear. This compressed the spring with 175lb preload(350 springs). Another way to think of it is the car at rest compresses the spring anyways due to corner weight is more than spring rate.

After lunch it was back at it. Entering the same turn now the car sat flat like a pancake in the rear and both wheels stayed on pavement had lots of traction. The engine no longer revved and both wheels were hooked up. Why? Load transfer is less from the inside wheel, and gravity doesn't turn off. Limiting droop keeps the car from moving as much weight on those wheels. It's not the same as stiff springs IMO. If had stiffer springs in the rear would just do doughnuts(been there). The droop limiter doesn't stop the car from rolling in compression allowing outside bite. The car still rolled in the turn. All I did was decreased droop until the inside wheel touches pavement at an acceptable angle to provide traction. The car lapped the course faster each time.

This seems to work on high grip tracks only and falls inline with what the RC crowd already knows.
Another side effect of limiting the rear droop is braking. By limiting the rear droop, weight transfer to the front is less. Noticeable right away once hooked up the droop limiter. Just keeping the rear springs in the seats had to adjust the brake bias more to the rear since more weight was now on the rear under braking. The further decreased droop had to dial again more rear braking to keep the fronts from lockup early. This has improved braking stability and shorter brake distances. Weight on the back during braking is much more stable than allowing everything to shift to the fronts.

Overall this has been a game changer and eye opening experiment. A piece of cable has transformed the car. With the rest of the car setup well, this has been an area worth looking into. All I can say is seeing was believing.

The standard cable gave insight that it works. I've since added a turnbuckle cause trying to adjust just the cable nearing zero droop takes too much effort. With a turnbuckle its very simple to get exact, and make sure both sides are equal. Not wanting to rely on a cheese grade one from the hardware store, I whipped up a functional one from extra parts. Piece of swedged moly tubing for a 1/2" tierod cut and welded to shorten it up. Used a left hand forged clevis to bolt to the underside with 3/8 bolt. The other end is a 1/2" endura moly heim (hey it's what I had for free already). Plenty strong for this application.

Lot's on the interwebs when tried to comprehend this topic. Seems there's tons of misunderstanding and confusion. I give credit to my Aha moment to this youtube video.

[autox320]

Put the autocross tires and pads back on to make the final Day Series event.Nice way to finish the autocross season with another FTD. Managed to just edge out the modified exocet and the kart. Right away a few members were asking us what we've done to the car cause it's so "hooked up". Dad tells them we've been adjusting suspension droop settings. There were some blank stares, but i'm sure google will be busy. Droop testing still ongoing for front and rear. Results are speaking for themselves. Think we can pull off zero droop rear for autocross if there's enough brake bias adjustment left in the system.

Interesting vehicle to me that showed this event was the Mclaren 12c. It's driver disguised as a "novice" (less than sec behind top times) was more than familiar with the car and course driving. Leaving the insane engine output out of the equation. But from one view it still had to get it to the pavement so worth noting. Getting that power down in style compared to a corvette requires ingenious suspension. Seeing a car like this on an autocross allows a close up view what good tires with the kinetic suspension system can do. It was definitely great to watch it in action. I'd put on level with the magnetic setup the Ford gt350 uses but i'm no expert on either system. Good reading if search the systems setup / layout. It ties all 4 dampers joined together to control the hydraulics.

My buddy's sister signed up to co-drive with us. She's been running with the club probably since birth. Of course guys like seeing a chick drive a car, so here ya go.

Debra


Dad


FTD

[m60b30530i]

Very nice dude, car looks a lot of fun to drive. I just re did my rear suspension setup, relocated the coil overs to the stock e30 shock mount location.

Car seems to like 400lb springs in the rear at that location.

How much negative camber you running in the front ? any toe out ?

[autox320]

Very nice dude, car looks a lot of fun to drive. I just re did my rear suspension setup, relocated the coil overs to the stock e30 shock mount location.

Car seems to like 400lb springs in the rear at that location.

How much negative camber you running in the front ? any toe out ?

Thanks man.

Front camber is -2.25 deg with front toe IN of (1mm/side) 2mm total. A car this light and geometry sorted I like some toe in for stability on high speed straights. Tried 0 toe and it's sketchy having to tweak the wheel down the straight. Toe out 1mm per side on say a larger chassis E36/E46 where they need the quicker turn in seems to help. Also with front steer the toe out loads the tie rod ball joints to keep a reasonable straight line stability. Rear steer doesn't seem to like it. If low speed maybe could manage ie autox but I keep the car set for track alignment regardless autox/track duty. Makes my life simpler on setup Besides we get plenty of turn in with the steering geometry and additional track width.

[OLD MAN]

Sweet!

I changed my droop the $$$$ way when I order our new rear shocks. One travel "long droop" is needed off road -jumps, not so much on road though.