We have decided to do some upgrades with Chris' bug for the 2013 VWMA VW drags .
I have ported another set of Type-1 heads with 44mm intake & 37.5mm exhaust valves , reset the compression ratio to 9.9 , and I am in the process of fabricating a new larger intake manifold & new larger turbo header .
For now Chris will be using the same tiny T3 turbo & 45dcoe sidedraft weber carb , so it will be interesting to see how much power gain we will achieve with the new improvements
pictured are the new heads next to Chris' old heads which had 40mm intake valves & 36mm exhaust valves with much smaller ports
Interesting intake knife edge ports Wayne.... And I also noticed you going with the 'Y' shaped central intake... Huge size upgrade there.... Will that lil T3 be able to fill it?
westi wrote:save time buy a tig,if you don't know how to use it,i'll teach you.
thanks for the offer Brad , I do have a TIG at my shop and have been teaching myself to use it on aluminum whilst I have been building the new circuit car .
My aluminum welding is getting much better and I am very happy with the results so far , however I have not had the time to stop and play with it on steel yet .
I will get around to it soon , but for now I am fortunate that we have a good team of members that all pitch in and help get things done , so I can keep productive whilst they clean up after me ( grind welds etc ) , and besides that there is plenty of time for grinding between 6pm & 1am 😂😂😂
Chris completes the installation , we set the fuel pressure & the engine is fired-up .
A new Aeroflow oil feed line is installed to the turbo and the turbo cartridge is rotated to keep the oil feed line inside the body
The weber carb now also sts outside the body ..... the carb will be fitted with longer ram tubes also
All sounds good for the dyno this afternoon .....
yesterday we did have quite a lot of trouble with wheelspin on the dyno , but managed to strap it down tighter to gain some grip .
The problem we faced was how uncontrollable Chris' bug became when it came on boost . There just didnt seem to be a mid-range area to assess the air-fuels as each time it was loaded-up on the rollers it just errupted !!
It made 294.4hp @ the wheels on just 10psi boost before pushing the copper 0.060" head gaskets out between the head fins .
So yesterday afternoon it was back to WPVW , put Chris' bug on the hoist and dismantle for inspection . Head gaskets pushed out of shape on all 4 chambers but no damage to the heads or the barrels .
I decided last night to remove all of the barrels to install 0.060" barrel shims rather than run the risk of moving the gaskets again . Everything cleaned & reassembled & engine fired at midnight , ready for another dyno session today .
I also decided to run the dyno wheels from my oval on Chris' bug for the dyno session today to gain extra grip and a larger rolling diameter , hoping that we will have more of an opportunity to monitor the air-fuels
fitting the dyno wheels to Chris' bug was a very good move as it gave us the added grip on the rollers and also gave us more time to monitor the air-fuels without wheelspin .
However , on the 3rd power run the flywheel decided to part company with the 8-dowel crankshaft as you can clearly see on the dyno sheet as it lost drive .
Chris' bug produced 305hp @ the wheels on just 10psi boost and was going to make plenty more , looking at the power curve . Luckily this happened at the dyno and not at the track !!
Time for a flanged crank , alloy case & 10mm headstuds I think !!
How close in diameter were the tyres between both sets of runs and what gear was each done in?
Sorry to hear about the flywheel, hope she's back on track soon!
