Bob Johnson with our Block
As I noted in the last post (here), we managed to get the engine out of the car and over to the home/shop of our wonderful engine builder Bob Johnson. Bob had the thing torn apart within something like an hour, or at least it seemed that way. The guy is amazing. And given that he does all this work in his garage, his den, his kitchen, his driveway, etc. he has the most understanding wife in the world.
Once he had the engine apart, he started going over the parts and checking out their condition. We bought the car from the world famous Jack Beckman, and the engine is the very one that he used to win the Super Comp national title a few years ago. But it has had 290 runs since the last rebuild and we just weren’t sure what the inside was going to look like.
We’ve told Bob that our objective is to get a good, solid, and reliable engine, and get a few more miles-per-hour at the top end. We’re not trying to build an exotic 1200 horse monster, and we’re trying to keep the expenditures under control. So with that in mind, we started with the idea of saving most of the parts, yet still shooting for 900+ horsepower (up from what we think is somewhere in the low 800s).
Cleaned Up Pistons
Bob had mostly good news after the teardown, even for an engine with that many runs. The pistons were in very good shape, with just some galling on the wrist pin area. It seems the wrist pins were a little tight last time around and not enough oil got in there. But in general, they looked great.
The heads are an older style, but are in good shape so we’re going to run another year with them. A new set would cost another $3k, and would mean we’d need new pistons. That’s an expense we hope to wait another year to confront. We are pretty sure that, next year, we’ll need to go with new pistons (see below), so we’ll tackle the new heads at that time.
The block, a great Merlin piece, is in very good shape. He had it honed and almost all the scratches came out. There are some remaining, but we’ll live this year with them. Next year we’ll tackle the project of going to a slightly larger bore size with its accompanying requirement for new pistons (see above). But the block looks super, and now that Bob has painted it all a pretty black, it almost looks new.
Cleaned Up Block
We are going to replace the intake manifold. The current one is an older one, and Bob’s pretty convinced that a new Edelbrock Super Victor intake will give us a solid boost in horsepower. Mercifully, these aren’t that expensive, and rank high in the bang for the buck sweepstakes. Bob’s going to tweak it to match the heads and we should have a super combination.
We’re putting in new valve springs, just good insurance for another year of smooth running. But the valves themselves were good to go after Bob cleaned them up. We’ve decided to go with a new camshaft as well. The Comp Cams guy suggested we needed some more duration on the exhaust, so here again, we’re making an investment with a good return on the investment. And of course we’re replacing all the seals, bearings, and gaskets.
The last major update to the engine is we’re going to install an active vacuum system to provide negative manifold pressure. This will replace the puke tank we have in the back of the car, and should give us a solid increase in horsepower. Bob’s never seen a vacuum system add less than 19, and he’s thinking we’re likely to see something closer to 30 additional horses over and above the puke tank setup that we have today. This will require new valve covers, and we have a special surprise coming there. Stay tuned.
Most of the parts arrive here this week, so Bob can get it back together soon. Then we’ll head for the dyno to see how much we gained in the way of horsepower. Next up is the transmission. We’ve found some issues there, but that’s a subject for another post.
Thanks for reading, and stay tuned for more updates.