Sprite Race Engine Rebuild for Dave L

[MiniDave]

Dave missed the race in Texas last weekend due to health issues, but he's hoping to make the Lake Garnet Grand Prix in Oct with his Lotus 7. To that end I loaned him a stock cylinder head - he has an aluminum head on it now but he changed to 1.5 rockers and bent all the pushrods, since then even after replacing all the bent parts it hasn't run right, so I loaned him a stock cast iron 12G940 head to make sure that the aluminum one isn't causing the problem. I hope he gets well soon enough to finish the engine and get it running.....

[MiniDave]

Well, after 3 full seasons of racing, Dave's Sprite was looking a little tired, so over the winter he decided to spiff it up some - his decision was also prompted by hitting the wall on the last turn of the last lap of the last race at Ozarks last fall - not his fault, he spun in someone else's oil. He didn't hit it hard, but enough to damage his radiator, bend the front support and left fender.

Earlier in the season he'd had something hit his radiator and put a hole in it, with no money for a new one at the time he put a little JB on it, which seemed to hold, but later didn't and he overheated badly. A new head gasket got him back on track and he finished the season.

one of the things he wanted to do was fix some of the oil leaks, so we pulled the motor, took the pan, front cover, rear cover and a few other bits and replaced and put sealer on all the gaskets.....good news, it seemed to dry up all the oil leaks! however, now the clutch wasn't releasing.....after bleeding it a hundred times we bit the bullet and pulled it back out, sure enough a spacer on the Tilton race clutch had dislodged and was keeping it from releasing. He'd had that happen before unfortunately and we're going to devise a way to keep it from happening again.

While we were in there.....we ran compression and #4 was 60lb.....ruhroh.......we popped the head off and found no issues with any of the valves, but #4 cylinder had a huge ring groove at the top of the cylinder, and the piston was very loose in the bore. We decided not to go any further on the teardown at this point. He has another block he can build as this one is already 70 over, but he needs to decide whether to go back all the way or only 40 thou or so, so he could potentially rebuild it one more time if he had too.

Part of the work we did included a new radiator and front support, some new lines for the oil cooler, some wiring improvements, relocate the battery, added a fire extinguisher system, welded up a crack in the frame and a couple of holes in his header and quite a few other things with the goal of making the car even more reliable....which is hard to do when you're racing on a small budget.

We were really fortunate to have the use of a friend's shop and lift, tho with no heat and overnight temps in the teens it was not fun. We had two propane heaters and two small plug in heaters going and that helped a lot....we burned thru two of the small BBQ size propane bottles and half of a third.