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Love what you did with the shifter. I need to come up with something similar for mine. as always you are an inspiration.
Originally Posted by mustanghammer
I got the cover fabricated several weeks ago. I started with a 4 piece poster board pattern that turned out to be close to perfect. I wasted allot of time beating on the aluminum parts I created and should just trusted what the paper was telling me. I figure this took about 15hrs of work from design to finished part.
The cover is held together with a mess of 3/16 closed end rivets and attached to the car using 22 10/24 stainless steel screws. The interior of the cover is insulated with DEI heat barrier and the Hurst boot seals everything at the top. The cover is removable to facilitate future trans R&Rs and shifter maintenance.
I was told that once a person drives a dog ring transmission they will never want to drive anything else. This is an accurate statement.
It is hard to describe how fast a dog ring transmission like this Jerico can be shifted. Trust me, it is lighting fast. Combine this with a ratio stack that keeps the engine in its power band all of the time and you have one happy driver. The only thing getting more of a work out than my right arm is the shift light. Driving this car with this transmission was an absolute blast.
Then it broke
Not the transmission (this time) but rather something more mundane - a suspension mount. For the third link mount on the rear end I used a 1/2" shock mount. Something I have used on other cars to locate panhard bars and tri-links with much success in the past. Anyway, it didn't work this time and I know why. I needed to weld in the spacer that slips into place on the mount. This is probably one of the first things I fabricated for this project.
Unfortunately when the mount broke it allowed rear axle to fall forward and this snapped off the end of the drive shaft and broke the 8.8 Ford flange. Then the broken drive shaft flattened the exhaust collector and ripped the drive shaft safety loop out of the car.
Oh well, race it, break it, repair it - rinse and repeat. I have some welding to do
Ouch I feel your pain… I had a similar mount that came with the rear end housing in my car, it never failed but I was leery of it for just the reasons that you so graphically pointed out how much carnage a broken mount would cause. Originally I ran with stock upper links in place with foam bushings, which is required for the silly IT rules that you can add suspension elements but you can’t remove them, I ended up removing them to get rid of the annoying clanking noises. When I had to build up a new housing after bending ours due to contact I built a much stronger third link mount, all 1/8 inch and completely boxed in for strength.
You can also see in this pic the machined flange on the KIA housing which is a great place to mount your angle gauge when you are setting the pinion angle.
Got the car put back together finally (the exhaust repairs took the longest) and went racing again. This trip was to the Freedom Sprints at High Plains Raceway in Colorado. My first race out of division and my first race at an altitude above 3000ft.
I'll cut to the chase....I was slow, off the pace and didn't get allot of track time. However I did get past a qualifying session and made two race starts at the back of the field. While I certainly wanted to do more racing, my wife and I made the 1350 mile round trip to collect the race starts so I can qualify for the Runoffs. So the weekend was successful by that measure. Yep this is the **** you do to race an Indy.
So now I am left with a few minor issues to resolve.
First the car ran hot especially on Sunday. So far this has not been a problem around here at the three tacks I have been on (Heartland Park, Motorsports Hastings and Raceway Park of the Midlands). However this has me concerned because a car that runs hot cannot be raced effectively. I think my experience at High Plains was a combination of the altitude and a close ratio transmission that keeps the engine at full boil all the time. The altitude won't be a factor the rest of the year but.....I hate to take chances. So, I am looking at going to a 26x19" dual pass radiator to replace the 22x19" dual pass radiator I have now. Would need to get it installed before the next race at Heartland Park...a moderate amount of fab required.
Next I had a bit of a drive line vibration that started in 3rd gear at 8000 rpm. Worse in the qualifying on Saturday but not really an issue during the Saturday race. Could have been a stiff u-joint (new drive shaft) or it is possible I was too busy in the race to notice. Either way I will measure tail shaft end play and compare it to another RX7 in the shop I am in that also has a Jerico. By the way, a driveline vibration is normal for this car but before this last weekend it only happened in 4th at around 7500 and then faded by 8000.
Finally, the bleeders on the front turbo calipers are seized.....again. I talked a racer that is campaigning an FC in ITS and EP and he told me this is a "thing" that happens. Advised me to get these bleeders out and replace them with new. Guess PB Blaster will be my friend.
High Plains Raceway is a fun track and I would go back if the opportunity presents itself. I was able to get carb jetting solved (dropped two sizes on the mains and 1 on the air correctors) but will most certainly need a better cooling system.
Just throwing stuff out there. do you have any hood venting? that can sometimes make the difference.
Can't add venting to the hood unless the car came that way. SCCA rules and all that stuff....
The radiator is undersized compared to what everyone else is running with the same kind of engine/porting. Most of the guys are running a "31 x 19" dual pass which just fit between the frame rails.
I was trying to cheap out and use what I have. Also lighter cause it holds less water
Just throwing stuff out there. do you have any hood venting? that can sometimes make the difference.
Not allowed in STU specifically, or almost any SCCA classes in general. Irritatingly.
Stopping by the June Sprints this year and seeing some friends is giving me the urge to make another EProd car in addition to the STU Miata project. I have a driveline idea that could play with some of the weight breaks Prod allows but could still work well.
Not allowed in STU specifically, or almost any SCCA classes in general. Irritatingly.
Stopping by the June Sprints this year and seeing some friends is giving me the urge to make another EProd car in addition to the STU Miata project. I have a driveline idea that could play with some of the weight breaks Prod allows but could still work well.
What chassis would you use for the E Prod car? There are some interesting rear brake loop holes if you build an E Prod car using a drum brake car.
The SCCA rules are comparable to IRS regulations except that the SCCA rule book has more pictures.
I have about 5 rust (and title) free FB shells sitting around, one of which is already stripped of sound deadening, plus another 4-5 parts cars, plus two different EP bodywork mold sets I can borrow from friends, so... 1st gen, I think. I think I know what brake loophole you're thinking of... friend of mine who was towards the top ten at the runoffs just stuck with the GSL brakes in the rear, so I'm not sure that's as important of a place to find gains. I'm already looking at bits to go full floating hubs though, possibly fiddling things a little bit to go with Enkei RPF-1s in 4x100.
For where I'm running right now though (Midwestern Council) EP gets stuck in the same run group as the big GT cars though, I'd need to get a really good strut solution nailed down, and there's so much fiddling with suspension stuff. I figure Miatas are a good place to cut my teeth (T4 spec NC now, STU spec NA later...) and do driveline development on the NA one.
Just throwing stuff out there. do you have any hood venting? that can sometimes make the difference.
The SCCA Club Racing Board must be reading these threads....Hood venting is a proposed rule change for 2018.
Anyway, I have a new 26x19 double pass Afco radiator in hand but there is no time to install it before the next race. So I am cleaning up the radiator I have now (it was full of track debris) and will put it back in. There are a few more tweaks I can make that should help.
Determined that the drive shaft slip yoke is too short and was the source of the drive-line vibration because the tail shaft bearings were not being fully engaged. So I am replacing it with a longer one that uses 1350 u-joints. Replacing the flange yoke at the other end of the drive shaft with one that also uses a 1350 u-joint so everything matches up. Using 1310-1350 conversion u-joints.
Was able to remove the front brake bleeders. They look fine so applied some hi-temp anti-seize and put them back in.
Should be ready for the Heartland Park Majors in August.
That's funny that you had problems with the bleeders on those 4pot calipers. That's the one thing that hasn't seized on me over here in the salt belt lol. Having said that I've now jinxed myself...
That's funny that you had problems with the bleeders on those 4pot calipers. That's the one thing that hasn't seized on me over here in the salt belt lol. Having said that I've now jinxed myself...
Must be a heat related deal for me. So far I have only pulled air out of the rear brakes when I bleed the system though.
Thanks! I am thrashing to get ready but should get everything done. Will write this up later.
I was given a spot in the Mazda tent (Thank You MAZDA!) so come by if you are there.
Good Luck!
I saw Moser is projected to win with is Eprod Prelude, with Rivera in 2nd. That prelude has some serious power, and you know it has some serious development too.
I feel like my wife and lived almost the entire Runoffs experience.....we chased after parts/repairs in an unfamiliar city, worked on the car late into the evening, searched for parts and tools in the paddock and qualified for the race on last chance Hail Mary qualifying run. The only things we didn't do were get crashed and actually run the race. Not getting to do the later was disappointing but we still had a magical time. The IMS road circuit is fun to drive and completely in character with what you would expect at the Brick Yard - Speed, baby, speed!
So what went wrong....several things that were related and one thing one that was kind of weird.
Qualifying session 1 was on Monday with afternoon temps in the 90s. I went out on track at the tail end of a 61 car field that combined STU (my class) and Touring 2 (T2). Right off the bat things were just not right with the car. Coming out of the pits the car started loading up and I had to start passing cars to keep it running (this is allowed on the out lap). Once the plugs cleared out I started hammering the car and problem number 1 showed up - an extreme drive line vibration. I stayed out because I needed to find the track but this effort was cut short when a Honda in my class oiled down turn one and the session was black flagged (ended).
After getting the black flag everyone slowed down and proceeded back to the hot pits where we were queued up into two parallel rows while they decided what to do with us. This is where problem number 2 cropped up - extreme engine heat. Temps climbed quickly and didn't think fast enough. I should have pulled out line, stopped and waited for a flat tow pack to the paddock. Instead I stayed in line and then drove back to my paddock spot while my engine cooked. I made a bad decision and would it would cost me later.
Back in the paddock after session 1 I surveyed the damage. The upper radiator hose was spewing water at a plastic hose coupler (I found out it had melted later) but nothing else was amiss. The hose coupler would be replaced by a piece of 1.5" pipe nipple from Menards to fix the water leak. I decided the drive line vibration has to be caused by the driveshaft as I had it serviced in KC before we left for the race. All other related drive line parts - tail shaft bearing - had been replaced with new parts also before we left for the race. l also used the Tremec iPhone app to check the angles on the trans, drive shaft and rear end and they all checked out. So we took the drive shaft to Indianapolis Rack and Axle and they determined that the shaft was bent in the middle and out of balance. A $45 fix that worked. Unfortunately, chasing this down kept us off the track on next day so we missed Qualifying session 2 on Tuesday.
With the repaired drive shaft installed and the cooling system topped up, I attempted to start the car Wednesday morning.....this is where the weirdness started. The starter responded when I pushed the start button but engine did not turn over. I verified that the engine wasn't seized and that it would turn the rear when with the trans in gear when rotated the engine using crank bolt. So I dropped the starter to check it out and determined it was fine. Then I looked at the ring gear on the flywheel.....and......and....it was LOOSE. So loose that I could spin it around the flywheel with my fingers. ****.
Mazda didn't have a NA flywheel for 7.25" clutch in their trailer and a suitable flywheel/clutch replacement that would work with my Jerico transmission's 18 spline input shaft could be found. A fellow racer - Aaron Downey - did have an 18 spline alignment tool that I could use so that meant I could service the clutch. So we set out on the long process of pulling the trans, clutch and flywheel so that I could attempt a field repair on the starter ring gear. The repair consisted of copious amounts of red loctite and 6 1/8" roll pins to chemically and mechanically attach the steel starter ring gear to the aluminum flywheel. It worked and I completed reassembling the car 2 hours before the 4th and final qualifying session. Unfortunately all of the this thrashing meant that we missed another qualifying session....Session 3 on Wednesday.
One of the things that was listed in the race supplements for the Runoffs is that 115% rule would be enforced. What this means is that drivers must set a qualifying time that is 115% of the fastest time in their class. In STU a driver set a 1:48 on the first day of qualifying. This meant that to met the 115% rule all drivers had to run a 2:04 or better lap time. My fastest time from the shortened 1st session was a 2:13 and I had posted no other times. I needed to find 9 seconds on a track that I barely knew in a car that I had disassembled and reassembled in the last 24hrs using track tools....yee haw! To improve my odds I had Hoosier mount up my new tires - SM7s (205/50x15) for the front and 225/45x15 R7s for the rear.
For qualifying session 4, the SCCA separated STU and T2 into separate groups with each class getting 10 minutes to qualify. TEN MINUTES. I rolled off the false grid at the back of the field (I have the slowest time in the class) and went on track. Very quickly into the session I found myself completely alone. Which is good and bad. Good because no one was going to catch me at the wrong time and no one would hold me up. Bad because I had no "rabbit" to chase. I attacked the course. In several places I over-drove the track which hurt straight line speed. Overall, I drove well and the car was so fun to drive. Upshifting the Jerico without a clutch makes driving this car more like a video game than anything else. In the end I got it done.....I improved my time by 10 seconds setting a 2:03 which comfortably put me in the show....
But there was a catch. 3-4 laps into the session I started to see smoke in my rear view mirror. I figured it was a tire rub - the 225/45's were hitting the fenders. A check of the gauges confirmed this as temps and pressures were just fine. But it got worse. Soon there was smoke in the car with me and it was oil smoke. None of the corner workers were signaling me so I keep going. However I started losing traction (because I driving in my oil) and I caught a glimpse of my self on the Jumbo-Tron trailing a decent cloud. So I pulled off the track and was flat towed back to my paddock spot.
When I got back my wife informed me what my qualifying times were (I didn't know) and we tearfully celebrated for a few minutes. Then I looked over the car. What I first thought was an oil filter/filter pedestal leak turned out to be allot worse. A dowel pin leak. The leak of death. The car had bled 2 quarts of oil but was not hurt. I attempted the dowel pin fix that is described in numerous threads on this forum but it was not successful. In my situation the leak was too big. I considered pulling the engine and doing a rebuild but decided against it. I believe this failure was caused by the over-heating experienced in session 1.
So, I drove at Indy but didn't race there. I would have improved my time and I think I would been able to catch some people. The Woulda-Shoulda-Coulda will be used as fuel for next year. We will be back, faster and better than before......
Me at Gasoline FREAKING Alley!
In the Mazda TentI was here and it was AWESOME!
Last edited by mustanghammer; 10-03-17 at 10:41 PM.
Well nuts, man. I was following online and wondered what happened. Sucks that you didn't make it out for the race, but at the same time, it's awesome you made it out and I'm glad nothng worse happened. And in the end you were there and I wasn't.
I've got the bit between my teeth though - going to see if I can get to the level to show up by the next time it's in the Midwest, it all sounds awesome.
That's a bummer! But what will go wrong seems to always go wrong in racing. Just extra motivation for next year right? Sounds like the car was pretty fast though, I'm jealous that you got to go to Indy too
05-19-17, 05:33 AM
I think I know what brake loophole you're thinking of... friend of mine who was towards the top ten at the runoffs just stuck with the GSL brakes in the rear, so I'm not sure that's as important of a place to find gains. I'm already looking at bits to go full floating hubs though, possibly fiddling things a little bit to go with Enkei RPF-1s in 4x100.
