Or, "project Sow's Ear".

So my very first truck ever, which I enjoy a great deal (and probably a bit TOO much) is an HSP Tyrannosaurus with the VX18 engine. Being the kind of guy I am, and being that I don't know the history of this (used) engine, I figured I'd better crack 'er open and have a look inside.

First thoughts: "Crap, it looks good in here. I guess I can't justify a new engine just yet." Sleeve and piston are completely without scratches or scars, no pitting or burning, no coking or carbon buildup, nothing. Connecting rod is still nice and tight on the wrist and crank pins, with only a minor film on the wristpin end. Crankshaft looks brand new, and bearings feel great. Pinch is awesome - in fact, after I broke the sleeve loose and wiped everything down, the piston would try to push the sleeve out of the case at TDC.

I timed it up and came up with some rather awful numbers:

Crank opens 43 ABDC and closes 52 ATDC for 189* duration
Boost 53 BBDC for 106* duration
Transfer 57 BBDC for 114* duration
Exhaust 77 for 154* duration

The crank duration is about as much as I'd want for a low speed motor, but the transfer, boost, and exhaust are all a little low. The boost port is fed by a hole in the piston, and the hole & boost port are terribly poorly matched up & I'm sure the whole thing could be done better. The transfer port on the backplate side isn't terrible, but the one on the flywheel side is fairly shrouded by the unfinished machining in the case. The transfer ports are both way bigger than they need to be, as they come down far below the piston crown at BDC. The exhaust port doesn't match up very well with the case, either - the top edge of the port and the top edge of the case make a step that can't be seen, only felt. The crankshaft bore is TINY.

Now I see why everyone says "just don't bother".

I've already got a Redcat tube header and a Team AE torque pipe on this engine and they seemed to wake it up quite nicely, but I can only imagine what'll happen if someone ports the thing. Well, I can't ONLY imagine... I can do something about it. I've got a new connecting rod to install because this engine spent a bit of time at WOT without any load, and because I don't know the history, and because I know aluminium will fail eventually, but while I'm in here I might clean things up a bit. I might go a bit further later, when I've got a bit of time.

I'll be updating this post with pictures when I get home tonight.

Has anyone done any work to these things, and how did it work out? I've seen one member post pics of a bit of sleeve work he did, but I haven't read any reviews on what it did for him. Anyone else?