The rest of 2016 was used for testing and feeling out the S14 at a bunch track/test days and rebuilding the KA so we could sell the S13. We found a few gremlins in it, like any car. Mainly the high pressure power steering supply fitting at the rack (the Fragola/Earls fitting everyone uses to convert to AN lines) blowing O-rings every 2ish hours of track time. The shoulder diameter that the o-ring seals to was a hair too small causing the O-ring to slightly stretch into a void and rupture. So I machined my own from an M14x1.5 bolt on the lathe based on the OEM fitting dimensions, which resolved that:
The transmission (CD009) shifter linkage that came with the car also had terrible feel and vagueness to it that was not confidence inspiring at all. I think it was a McKinney unit. I ordered the GKTech shifter setup to replace it, which does away completely with the OEM U-Joint linkage and picks up the selector rod directly. It is a significant difference in feel. The spacing between gates is very close, almost too close, but I think that’s the nature of picking up the selector rod directly. It’s something that is much easier to get used to than the weirdness from the original setup.
[Interesting comparo vid I made to see how I differ from my co-driver when we first got the car. Also notice I have issues shifting into 6th. 4.08 final drive):
https://youtu.be/bATszqztrko?t=30s ]
It didn’t come without its issues though. First being the reverse lockout pin and plate was incorrectly spec’d in my batch with mild steel. Within only about 4 hours of track time, they wore enough to make it almost impossible to shift into 5th and 6th without readjusting it:
I informed GK of the situation and he sent new shift rods with pins and plates to everyone who got a kit from that batch. That didn’t happen quick enough for me at that moment so I made an overkill solution with O1 tool steel plate hardened to ~50 Rc and dowel pin stock.
The other issue is the shifter getting stuck when you go to push it down to get it into reverse. Still need to delve into this. The shifter rod sits in a plastic housing that sits on top of a spring in the main metal housing that you compress to clear the lockout plate. My guess is that the plastic is scuffed or messed up from the heat generated from racing and not sitting properly in the main metal housing where the spring sits. It’s something GK is aware of and awaiting my findings. The customer service from them has been excellent.
Race prep time for AER Watkins Glen April, 2017.
Engine pulled:
For oiling reliability we installed a Cosworth oil pan baffle kit and AAM oil pan spacer. Oil capacity now at 6+ quarts:
Also installed a new VQ35 rev-up oil pump to handle the sustained high rpm use. This VQ motor makes excellent oil pressure using 30wt Redline Race oil. About 80-85psi in the upper rev range under WOT with oil temps at 240-255F.
I scored a great deal on a used AiM MXL PISTA datalogging dash with a GPS05 sensor (10Hz). This is one of the best things I’ve purchased yet for the race car. It’s expensive, but for good reason. This allows complete driver analysis and enough resolution to monitor oil pressure in turns. Needed a solution to mount it in my bare interior and came up with this to mount directly on my steering column (I can make this for anyone wanting a solution to mount their AiM/Motec dashes):
In AER, there’s a minimum pit stop time of 3 minutes, which is plenty of time to re-fuel, change drivers, and go over vitals on the car. It also prevents fueling rig cost creep for all teams so we’re not forced to use dry-break systems to be competitive. Ironically, there’s no pit time restriction in 24HoL (5 minutes in Chump/Champ) and there are some top teams with fuel fill systems that are more expensive than the car. I just drill out the flappy door thing from the OEM filler neck and use Hunsaker quick fill fuel jugs. Takes about 20-25 seconds for 5.5 gallons of fuel with OEM venting.
Also removed and replaced the existing wiring harness and power distribution box with a more robust kit from Painless Peformance. The existing power distribution box had only 2 relays for all the circuits in the car and suspicious wire sizing. We ended up using the 10 circuit race only chassis harness as the replacement. I would’ve like to have gone with a solid state power distribution box/harness, but they are more than double the price:
Old:
New:
Wiring is the best!!:
Did our own version of the Pathfinder coolant tube bypass mod on the rear coolant pipe by the firewall instead of piecing together OEM parts which adds $$$ up quickly. Whether this actually improves cooling efficiency or not is debatable. I like the idea of it at least so I figured it wouldn’t hurt and *should* provide an additional exit for coolant at the back cylinders.
While having everything out we also discovered the transmission front cover shaft the TO bearing slides on was completely broken off. Not sure why this is yet or how long it was like that for, but it at least functioned that way. I’m hoping that it was just too much clutch pedal movement so I adjusted the clutch pedal stop to provide the minimum amount of travel required to disengage the clutch. The verdict is still out if this worked. We’ll find out next time trans is pulled.
Broken clean off:
Cleaned up and TIG’d back on:
There was an ACT unsprung 6 puck clutch disc with HD pressure plate in the car already, but it was unanimously agreed upon that we all couldn’t stand it and it needed to be removed. Surprisingly, the 6 puck disc is no lighter than the an ACT SS sprung full clutch disc so that solidified my decision. The main negative is that the springs in the disc add another point of failure that can screw us in a race. My fingers are crossed.
A Cosworth intake manifold came with the car and is gorgeous. Based on all the research I’ve done it seemed that it was best suited to be used on FI applications and actually hindered performance in the low-end to mid-range and negligible gains in top-end on NA cars. Unfortunately, I never got it on a dyno to actually prove that out. I ended up selling it and installed an OEM manifold with a ½” Motordyne plenum spacer kit. I regret it sometimes because 1) it was gorgeous and 2) it was very space efficient. I ended up having to space the hood a bit more to clear the OEM IM setup. The hood spacing is one of my biggest peeves aesthetically on the car (in addition to the fender vents) so spacing it higher ticked me off. But, I sold it for a pretty penny and function >>> form, BRUH!
Motordyne:
Engine all buttoned up and going back in. Engine install # 5,173:
Mr. KA24DE isn’t happy about being replaced and eventually sold off
Lastly, fire system, communications, and center net installed. Want to also mention that we use a Schroth Enduro 6 point safety harness. It is by far the smoothest, and easiest adjusting safety harness I’ve ever used. Driver changes are incredibly easy with it.
Ended up borrowing a load cell from work to have fun weighing engines and transmissions because these were all sitting in my garage at the same time and why the hell not!:
KA24 stuff (484 lbs w/o PS and AC):
VQ35DE stuff (521 lbs):
And for sh!ts and giggles, arch nemesis BMW S52 on the scale (377lbs + 82lbs ZF trans = 459lbs w/o plastic IM) :
Unfortunately don’t have a pic of the ZF 5 speed, but it only weighed a feathery 82 lbs. Is it a surprise that the KA being an I4 is the heaviest of the bunch? Cast iron block, sure, but so is the S52. It treated us well even when we didn’t (unfiltered oil ), but good riddance. Maybe one day I’ll mate the VQ to a ZF…