Almost Ready for Our Next Race – 12 Hours of Sebring with SVRA

There’s been a two-month layoff since our first race, but we certainly haven’t been idle.

We were hoping to have our direct-drive gearbox and the higher gearing differential installed for the SVRA vintage race during the 12 Hours of Sebring weekend, but decided not to rush this job and will postpone it until after the Mitty at Road Atlanta at the end of April.

The opportunity to get meaningful tire temperature data has not been available, but we went ahead and made some changes to the front and rear suspension in search of better handling.

All our in-between-race scheduled checks and maintenance have been completed. The leakdown results were the same as before our first race–a good sign.

During routine inspection under the distributor cap, it was noticed that the witness marks of the arching from the rotor tip to the four cap posts were at the very tip of the posts. Also, there was evidence of arching from the cap center contact to the rotor. This indicated the rotor height was too short. The suspicion was confirmed after checking a few dimensions. It was discovered that the rotor that came with the car when it was purchased, although it appeared to be new, was actually for a standard PL510 distributor, not for the L20b distributor. A new, correct P/N rotor put this right.

The gaps on all four Champion C57 sparkplugs had widened somewhat and, while resetting the gaps, a crack was discovered on the inside radius of the ground electrode of one of the plugs. We were lucky it didn’t break off in the engine. The color of the C57s was good, but our new spare set was Champion C59 (one step warmer). The C59 plugs have been installed, and we will do a plug check after our practice run at Sebring.

The issue of the Champion plug ground electrode crack is very disturbing, as we had never experienced structural failure of a plug before. We have purchased a set of NGK R5671A-10 and NGK R5371A-9, which are of similar heat range as the Champions. The NGKs have been gapped and index-marked and are ready for action.

It was noticed, during the gapping process, that the force required to change the gap on the NGK plugs is much higher than on the Champion plugs. This indicates, at least in this respect, that the NGK sparkplugs are more robust than the Champion sparkplugs.

We plan to do our practice at Sebring with the Champion C59 currently installed to get a comparative plug reading. From then on, the “Champion” logos may remain on our BRE Tribute car, but we’ll run NGK exclusively.

We have ordered a second set of Panasport wheels to replace the American Libres currently on the rain tires. This will make tire changing easier, as the the lugs for the Panasport and Libres are not interchangeable. The Libres are genuine aluminum race wheels in excellent condition. They have glossy black spokes and clear rims, and we plan to sell them.

A change in our yellow Datsun 510 car number from 33 to 38 was required for this next race. If you’re at Sebring next week, stop by our trailer and say hello.

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