vw brabham versus vw spiess F3

[peter holst]

does anybody know how much better/stronger the Spiess unit was in the beginning of the nineties?

[ralt-racer]

Originally Posted by peter holst

does anybody know how much better/stronger the Spiess unit was in the beginning of the nineties?

I ran both in ARP and the Spiess was not actually much better but did have the advantage of the wider cam belt which was a definitely a good thing, I had a Brabham engine jump a tooth and totally destroy itself even more annoyingly I was 5 laps in to the race and 5 seconds in front. The Spiess we used had to have new MBE ignition fitted due to the old unit failing this may have clouded the power output but it was marginally more powerful. I'd personally give them both a miss they are nothing but trouble we spent thousands on them and each season had nothing but issues.

Good luck

Benn Simms

[peter holst]

thanks for info Ben

I would be interested in knowing what to look up for because I am the "lucky guy" with an judd engine.

[ralt-racer]

Hi Peter,

Well from memory (which isn't my strongest point) we had the following problems with the judd / brabham type

Crank sensor, the engine had a gems (I think) Ecu fitted (little aluminium painted red or blue box) which basically just did the same job as the dizzy would have done ie max advance timing from 4000 onward this had a very small 4mm ish round magnet in its round red anodised crank sensor which fitted over a trigger wheel located at the front of the crank. The magnet fell out!! it was just bonded in with something like araldite happened at Pembrey 4 laps in to testing for a weekends race.... the sensor was inside the tub and the engine had to be removed to get to it...We went home.

Starter motor would fail regularly after 4 or so uses due to the position under the exhaust manifold cooking it, Id have to rebuild it each time cleaning the copper disk and contacts inside it. It also used to twist on its original moults so we also added an extra moult on the back to hold it in place. once the engine was running and on track you just could not get it to crank until it cooled down.

There is also a little wire inside to trigger the solenoid this regularly broke and I think that was due to the vibration.

Starter motor on the ralt rt32 and 34 were coupled to the small flywheel with a jack shaft that had 2 knuckle joints in its design, these would regularly fail and the starter shaft would then jam in we had it throw one once out of the side of the car in the pits.. could have been bad that..

Carry plenty of very high quality spark plugs we would get through them like shelling peas.

The engines run high compression so use the highest octane fuel you can and listen for detonation, given a flat out throttle under 5000 rpm and it'll detonate.

The clutch on one of the engines would drag badly turned out to be a plate tight in the assembly.

Fuel metering belt from the cam to the metering unit would jump particularly on race starts the car would still run ok and sound ok in the pits but would be down on power.

Cam belt jumps as I said before make sure its set correctly and there is no oil leaks.

not sure what car you have but if it was a Ralt then we had a few issues with the clutch release bearing the seals would stick to the piston and roll up inside the gearbox housing you also need the correct quality oring seals as std ones will not work.

Fuel pump pressure problems fit a new pump and wiring harness

We had a block crack but I think that was due to the car not having the correct engine bracing fitted.


Think that's about the lot seriously hope you are not as unlucky as I was the Ralts were really great fun fast cars I do miss driving them.

Benn

[peter holst]

thanks Ben

has there ever been made some kind of manual for the d....engine?