hrnts69

iTrader: (5)

Hey yall, i figured ill post this here since you guys have some of the baddest small blocks in this hobby!

I race R/C Dirt Oval. I race on loose tracks, so pure HP aint all that important. If i raced on a Clay track, then i would be going with Nova 353. Iam gonna be running a Thunder Tiger .15 and a XTM .18. These are both pull starts. Iam wanting to build them up for this years racing.

I printed out the article that RCA did a long time ago. Which said to smooth out the ports, sleeve. Which iam gonna be doin that. But what else can i do to them to produce more HP? I dont wanna mess with port timing, if i wanted to do that i would send it to a modder.

Do you guys have any more ideas/tips?

Thanks
Blake

Roelof

If .18 is alowed the OSMAX 18TZ is the way to go,.

Your mentioned engines are running on a plug R3/R4?
You can raise the compression by taking out a headshim with using a colder plug (5 or 6)

Drill up the carburator by 0.5 to 1 mm can give more power.

A longer exhaust system can give more bottom power.

Higer Nitro content.

chunk t

Hrnts,

I'd like to add that if you can provide measurements of the engines, then maybe we could give a few other "simple" options. Shimming the sleeve may be an option depending on the current port timing. Knowing the actual head clearance and total shim stack, removing/swaping head shims may give a boost. But without knowing where the numbers are when you begin, any change is simply a shot in the dark.

If you can give me some numbers off of the engines I can tell you where you are and maybe prognosticate the results of some of the "simple" changes offered.

1. head bubble volume 2. head insertion depth 3. shim thickness 4. rod length (c to c) 5. sleeve bore 6. port measurments, exhst/boost/trans (top of sleeve to top of port) 7. TDC (top of sleeve to piston face) 8. BDC (top of sleeve to pistion face). If you need I can talk you through taking the measurements.