A heart with no body; the Turbo 10hp Briggs & Stratton. Aka Timebomb.(56K beware!)

[65ShelbyClone]

I know mdb mentioned my project a few times, but rather than derail the "intro" thread, I thought I would showcase the whole thing here where I have the room for pictures, commentary, and feedback. You all seem to like old stuff, weird stuff, and going fast, so I'll share my old, weird, and hopefully fast engine.

I usually have time to let my mind wander and my interest in fast cars led to interest in powerful engines. Putting time + interest together, I got the idea to turbocharge a lawntractor engine. I already had the engine from a Montgomery Ward tractor and a small spare IHI turbo from a DIY turbine engine project.This was the original idea circa 2001-2002:



I wanted to squeeze every last drop of power out while spending as little as possible, so I studied some on old school flathead porting techniques and went nuts on the Briggs. I didn't have any fuel parts or plan at this point:







Oh yeah, and some DIY titanium retainers:


I wanted to be able to intercool it, so a draw-through carb setup was out. That left the options to a blow-through carb or EFI. Since they both needed nearly the same fuel system components, I decided on EFI. I and had the idea to retrofit a system from an '89-90 Nissan 240SX:



After literally weeks of intense research, it became clear the the Nissan JECS system was going to be a tuning nightmare for something this far removed from the original 2.4L engine. It can be chipped and tuned for a car just fine, but not this; I would be in uncharted territory. After several months of tinkering with and studying electronics, I broke down and bought a MegaSquirt EFI computer kit(assembly required).



I already knew my "small" IHI turbo was far too big for what I wanted to do, so I started looking for the smallest one I could afford. After a few months of searching, I scored this little Garrett GT-15(far left, IHI right):



I had to build custom flanges for everything. Luckily I was working in a machine shop at the time.


Preliminary turbo header made out of pie-cut 1" steel water pipe:


Preliminary intake manifold:


Soldered fuel rail and Nissan regulator:


Modified Ford in-tank EFI fuel pump.:


Billet aluminum turbo oil drain I hacked up over a lunch break:


Mockup:


Setup as it stood when I first started the engine:


At first startup I had a Honda XR600 carb I was using as the throttlebody. Since then I picked up a pair of EFI throttle bodies from a Suzuki street bike. The intake design has turned out to be a POS, so I'm redoing that right now.

I'll cut this a little short(?!) since it's pushing 1am here. Questions, comments, and recommendations are welcome. Hopefully I put this in the right forum.

[minidragbike]

Nice layout!

[jesse8931]

omg that is soooo cool

[XDEEDUBBX]

Omfg..that Is The Sexiest Thing I Have Ever Seen!!

[offroadwhatever8]

That is sick! good work man!

[65ShelbyClone]

Thanks y'all. In the next two weeks or so I expect to have time to start fabricating another intake manifold. Short of a self-contained oiling system for the turbo, that's really the biggest hurdle right now. Behind those I guess would be full ignition control and rev limiter/flatshift/turbo anti-lag, which I don't have set up yet.

I really wish I still had the 16hp Briggs iron-block flathead I sold years ago(for $80 ). It would have been great fun to intall a rod, piston, and full pressure oiling on that. Heck, If I was still working in a machine shop, I could have built a billet OHV head for it, kinda like how Vogel put a Kohler 361 OHV head on one of their Jones 341 flathead blocks.

Hey MDB, I got a wild hair and started looking at fullsize drag bikes to get ideas for a frame design. I have something in mind that will be about 1/2 to 2/3 scale and most likely will have a Vaguard twin of some kind. I want to avoid a bike engine if I can. Not really a "minibike" if it has a motorcycle engine....

EDIT: I almost forgot this...

[minidragbike]

Something like this one!

[65ShelbyClone]

Yup. I was thinking of that picture too when I decided on a direction to go.

Might hook things up to a 4-speed transmission of I can find one that isn't priced like gold.

[XDEEDUBBX]

you should throw on a blow off valve on it, it would sound sick and help as well!

[x-90 rider]

65,

Here is an example that is available at most Harley dealers. We are planning on a 1/2 or 1/3 scale with a Vanguard V-Twin engine.