The weeks preceding the event went by like all the other, check and prepare the vehicles, except Mike fitting power steering to his VW Fox. Everything went smoothly with the installation with one or two issues presenting themselves, understandable if you consider the MK1 Golf/Fox shell was never intended to utilize power steering. Saturday morning 6 o’clock arrived and we started our little journey to Piketberg, on our way to the little town we noticed outside temperatures of 3.5degrees, luckily we packed enough warm clothes to battle the temperatures.
On arrival at the Piketberg Municipal Testing Grounds, we found ourselves a very nice location next to the start/finish on the Piketberg hospital grounds which served as the pits for the day, this allowed us to have out Gazebo’s next to the vehicles which helps allot especially with the vehicles being used multiple times on a specific round with different drivers and navigators. We went about the usual, setup the gazebo’s unpack the gears etc., then moved onto the vehicles. A frames were removed, racing tyres installed and all necessary suspension changes made to accommodate the short bumpy route, seeing that it was so cold outside; tyre temperatures was very high on the list of preparation work. Being the first time that the Race-Tech crew were participating at the event, everything was new to us.
Pietie unfortunately had to cancel his entry with the Mazda F due to improvements currently being done on the vehicle, due to this he could focus on his FWD entry with Mike next to him.
Bjorn Venter and Jan van der Vyver in Class D VW Fox 1.4i – 1st in Class D and 1st Overall
Jan at last convinced Bjorn to start competing again and what a result he achieved with on his return, Bjorn drove magnificently throughout the day, the two of us even disputed his first time and was under the impression he received an incorrect time and waited for round 2, if he could match the time we knew the 1st one was valid. He finished his second round 2 seconds faster than the first round and to make matters worse for the quicker classes was that his time was one of the best for the day in a 1400 powered vehicle which left the rest shell shocked. To sum it up Bjorn slightly bettered his 2nd round time with round 3 and took overall victory on the day, 2seconds faster than the overall championship leader Izak van Zyl piloting the Dynotech turbocharged VW Golf. Quite frankly a shocking surprise but well deserved.
Herman Mathee and Mike Mathee in Class F Datsun 1200 – 1st in Class F and 6th Overall
Having been a quit day for me on the navigating side with only 3 vehicles, which was 6 positions from each other provided me the opportunity to watch some gymkhana for the first time in the last 2 seasons. After making some improvements on the Datsun’s camber/castor plates setup time was reduced considerably. Luckily for me Mike went out on the route before me and could provide with some vital information regarding the track conditions and a few heads-up. We launched nicely, as we moved thru the middle section of the course it became apparent that today is the day that the “Lil Datto” is going to spend a lot of time at 7500 rpm. The first run I used to get familiar with the route and track conditions. On our way from one corner to the next we were sitting on the limiter in 1st, just tapping of at corner entry and then the same all over again. We finished the route with a time of 1:15.26, which we were actually happy with as we knew their isn’t a lot more in the car. This time placed us in 4th in class after round 1. As I did my duties as a navigator the track became warmer and warmer, which could definitely been seen by the other competitors times.
We entered round 2 with the impression that if we could match or slightly better the time we would be happy as we just didn’t have the legs with the car and changing to 2nd could become a problem. We drove thru the route with the car more on the limits, actually started to feel quite sad for the poor thing, but being a A series Datsun motor that thought quickly disappeared. We finished the route with a very impressive improvement and ended posting a time of 1:11.26, which we found quite astonishing. This time promoted us to 1st in class provisionally.
Standing in the line waiting to get to the start was probably the most nerve wrecking to date, as I was currently leading class F with Mike’s car and it would be a first for the car if I could win the class. This particular car is really surprising us race after race, as it is basically just a bunch of slapped together parts that is actually working quite well together. As we pulled away my brain was just telling my arms and legs to do exactly what they did in round 3, but my thoughts was causing the chaos, constantly reminding me that I need to perform if I want to win the class as there was another round after this one. We had the car on its limits throughout the route, but only managed to post a time of 1:12.75, not as great as the previous one, this kept us in 1st place and .7 seconds in front of second place.
We were ecstatic with the day, but we still had one round to complete as
A12GX Head – A14 Sub – Dual SU's – Lightened Flywheel
What a busy few weeks getting the Bakkie in order.
Just want to give all that provided me with tips and tricks some feedback.
Got the Datsun
Comps spec on the flywheel, took the flywheel and a new pressure plate to the dude that does my machining, he got it down to 5.78kg, he also balanced the flywheel and new pressure plate for me.
Installed the A12GX head with worked ports and valves.
Fitted a 4-1 branch manifold, already had a 50mm Stainless Free flow System
HS4 Dual SU Carburetors, intake manifold ports matched to head intake ports
Fitted a electric fan, switch comes on at 85degrees, removed mechanical fan on water pump
Had to purchase a new Temp Sensor, could not get the old one out of the A14 head.
Here comes the interesting bit, somewhere down the line, they changed the resistance on these sensors, from about 560ohm to about 360ohm at 16degrees.
This caused more than enough problems. All of a sudden the temp gauge needle climbed way more that it should.
We started it up, all was fine, no bolts, pistons or valves flew around, tuned the su’s. The electronic fan came on, everything working as it should.
Once on the road it was a different story, torque there is a lot of, it is clean, revs up nicely, pulls excellent from 2k rpm right thru to the limiter (currently at 7k rpm), there is not even signs that you are about to hit the limiter, this means all is working together, producing nice bottom down torque and decent top end power.
Then, all of a sudden the motor gets hot. After a day or two and enough swear words to make a sailor look like a beginner. We figured it out. Once on the road there is enough air travelling over the switch to cool it down and not switch the fan on. This caused me more time under the bonnet than needed.
Obviously if the water gets way to hot, pressure builds
and want to escape somewhere, the place it picked was between cylinder 3 and 4 at the water ports on the intake manifold gasket. After taking it apart, I also noticed that the one exhaust manifold washer was pressing against a piece of welding on the branch. Smoothed it down, reassembled the lot. Also re-fitted the old mechanical fan on the water pump to be on the safe side.
Took it for a drive, no issues what so ever anymore, the fan doesn’t even switch on after some heavy spinning and gymkhana practice.
Saturday we have our next race meeting and look forward to the added power and overall better A14-A12 inbreed.
Just hope I will be able to keep the wheel spin to a minimum, we are expecting rain also, and that sure as hell wil not help.
Thanks a lot to all that helped and gave advice. Special thanks to Einstein(My Brother), My Father and Ruan.
Dual SU Carbs
Just a quick heads up on the Head and Carbs for the Datsun.
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The A12GX head is all cleaned up. After a 2 day long cleanup session, everything is ready for
fitment.
Ports is as clean as I can get them, gasket areas are shinning and ready for some new ones. The valves Seats are grind.
Yesterday, me and my brother prepped all the clean parts and reassembled the head. It is know wrapped and waiting for an installation date after the 2nd May 2009. We have a month gab between gymkhanas after the 2nd, so this will be the ideal time to install all these parts and eliminate all problems.
The HS4 SU Carburetors have been stripped and checked; so far I can so no damage to the parts. No cracks, holes or excessive wear. The next steps will be to get this all cleaned up for further inspection and reassemble them. Then they can also move next to the head on the shelf for installation.
This is killing me, knowing I sit with all these parts and have to wait to get them installed, o well; at least it gives me time to get everything ready.
Electric fan must be installed and wired up, the
brackets for the helper leaves on the back suspension need to be made and tested. Hope this stiffens it up nicely, could be a cheap mod for starters to the back suspension. The branch must be sources and wrapped with Heat Wrap, and let no one tell you different, this exhaust wrap is expensive, R450 for a 15m roll, just enough for a 4 cylinder branch.
I’ll be off to go pull some more hair, this waiting is killing me.