Well we got Marks turbo truck pretty well sorted out. We finished the rear axle mods and got the back of the truck down where it belongs, so with the new wheels and tires it looks great. Complete with wad of bubble gum Bondo patch. I really dig it. Looks really “right”
We also finally got the boost control sorted out, figured out our fuel supply issue and dyno flogged the thing. On 8 PSI it made 301rwhp and 383rwtq corrected. Really not to bad. Its what we were going for, 300hp for a super small investment. Considering a “good” running small block chevy makes about 260 rwhp AFTER it gets sorted out, I think this is a pretty good win. Normally $3-4000 dollars would have been needed to put a motor together that would run this well NA, and this one does it for a whole lot less, just look at the ZZ4 crate engine. Not to mention it has all kinds of under the hood cool factor. During one pull, we screwed up and ended up making about 12-13PSI where we actually saw 345HP, but being non inter-cooled and being completely ignorant of the engines internals we wanted to stay at about 8 PSi and 300whp. At least until we get enough miles on it to where we feel like turning it up. But on a good note, the afr was still solid, so its in the future I’m sure.
Dyno graph below.
We ended up with a mechanical fuel pump that was boost referenced to the charge pipe, 23* of total timing, 68 jets in the primary, 82’s in the secondary with the power valve channels cut out to .083. If you look on the graph, that yielded a solid 11.2 afr pretty steady with good distribution according to the plugs. The carb also had a few other mods done to the vents, choke horn, floats ect to work properly in this boosted blow-through application. A quick rip around the block was pretty fun, wheel spin, good torque, easy to drive and a bed to haul stuff.
It still leaks oil like a big dog, and I still have no idea what engine it is, but who cares, it does rolling burnouts.
TW