OS 18TZ vs Traxxas 3.3 Engine Test
 

Just wanted to see what each of these engines could do in a Cen Magnum chassis now that they are both about the same price and available at less than $130 new. After braking them in and running them around for a few hours what I found is they are very close in performance. The 3.3 is a high RPM engine with good power from mid range to top end. The OS strength was at the bottom end to mid range where I had to back off numerous times due to wheel stands but did continue to pull hard through all RPM ranges. After running these two engine I find that they are as strong as some low budget .21 big block engines but without the high torque axle breaking issues. Of all the engines I have run in the Cen 1/10 chassis, Ofna .15R Force, .18 XTM, .18 DTX, .18 Sirio, OS .18CVRX, and .21 Vertex, these engines have the best performance to date.

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

Which one did you choose to leave in the truck? Did you use the Associated pipe for the O.S.?

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

hey Digout, good job on testing both engines... how did you manage to fit the clutch bell gears on the 3.3? any special mods that you had to do? i would like to the same to my Cen Magnum...please advise, thanks!

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

The best of the two so far is the TZ mostly because it keeps a tune better. Notice that I had to add the wheelie bar. The 3.3 was fitted to the chassis using homemade motor mounts cut from a 1/4" thk x 3/4" tall aluminum bar stock and drill/tapping holes where everything lined up. CEN'S adjustable motor mount probably also could be used with some height spacers. The Tower ST-15 is a good flywheel to use if you need a very thin one for tight clearances. The clutch bell and shoes shown are CEN's hop-ups.

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

Great looking truck! thanks for the info and posting the new pics.

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

Very nice! Looks like youve used every last bit of the longer chassis, good going. Any chance of a few more pics of it?

Does the increase in wheelbase make much difference to the handling?

Are the diffs uprated or are the stock ones ok?

Apols for all the Qs.

Oh - just a thought... I found that the engine plate can flex a little under heavy use, and could contribute to spurs getting stripped. I used some longer screws through the chassis and threadlocked some nuts to the extra threads - it seems to help a little. Not trying to teach you to suck eggs, mate. I wish Id gone for the 18 TZ too... [8D]

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

I was looking at an .18tz on ebay, just not sure if it would be worth the extra cash or just spend the £55 on a .18 cvrx?

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

Poor Performance: The increase in wheelbase helps in making those long jumps. The diffs are the stock ones in which CEN says are stronger this time around. Haven't broken any while street driving. I do not use the large heavy tires.... just Masher 2000s, Imex claw dogs and HPI Geolandar.

Scouser: The OS .18 TZ value over .18CVRX is about 7MPH top speed and guaranteed wheelies. I bought the CVRX for $95 and TZ for $139 at Tower Hobbies. The TZ just had a significant price reduction.

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

Lmao @ Poor Performance!

Cheers for the pics tho.

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

Yea me too....[:-]

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

digout, did you change the throttle/brake servo to accomodate for the 3.3 slide carb? also, would you have a part number for that cen clutchbell upgrade you have there? I checked out cen racing and i didn't see that clutchbell in there hop-ups... is it from the cen? thanks for posting these other pics..that truck must fly with the TZ in it.

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

think he said the clutch bell was a tower branded bell.
Timmahh

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

I have the same bell, it came with the optional 2 speed pack for the ct4/ff/super ten, the one with alloy spur hubs and green and yellow spurs. If that helps at all...

Im sure Ive seen it available as just the bell though, but cant find it now.

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

thanks poor judgement, i will look for it! do you guys have magnums nx's aswell?

RE: OS 18TZ vs Traxxas 3.3 Engine Test
 

Some people on here do yes, and some are in the process of swapping their FFs over to the NX chassis, some of us dont care for it and the rest have a JT chassis.