Here is my review of the all new Team Infinity .21 small block side port engine. To go from the beginning for those that haven't heard about this engine yet. This is a replacement for side port engines that are .12 - .18, its the first engine of its kind and I have been testing prototypes over the last 12 months, the final product that will be sold is something of a higher quality than I expected to ever see in this price range. For those of you who have owned the Infinity 18-S, you will be familiar with this engines increase in power over the standard VX18 and other 18 engines, so as a comparison I am showing you the difference between the already powerful infinity 18-S and the new 21-SP. We will start with the engine internals first, the differences are very noticeable.

One question that has been asked a few times, how is a .21 capacity acheivable in such a small engine? well there are 2 ways to increase an engines capacity, one is to make the bore larger, so a larger diameter sleeve would be needed along with a larger diameter piston, the other is to change the stroke. In the case of the infinity .21 they have done both, the standard .18 bore is 16.8mm, the .21 is 17.0mm. The stroke in the .18 is 13.6mm and is 15.0mm in the .21. The .21 has a longer conrod and also a longer sleeve.

SLEEVE

The infinity .18 sleeve is fairly typical for a side port .18 engine, the quality of material is better than something like the SH18 or VX18, but also not as good as you would find in alot more expensive pro engines. If you take a look at the below picture you will see the .21 is using improved materials with improved design. The exhaust port is slightly larger and it matches the port on the block alot better than the .18.



Here you will see the side intake ports and boost port on each sleeve:




Next we will compare the piston's, on the picture below you will see the speckled appearance of lower quality material in the .18, the .21 is a mirror finish, absolutely flawless. The .21 has got 2 groove rings around the piston whereas the .18 has only 1, all pro engines I have seen have 2. The .21 has a larger gudgeon pin, making it stronger to handle the extra power. The conrod is also longer, thicker and made of better material. You will notice the dull finish on the .18 conrod.



If you look at the picture below you will see that the crank in the .21 is larger, this means the engine block has a larger rear bearing to cater for the larger crank. The inside of the crank is hardcoated, its is almost like a teflon type slippery material that you find on frypans, this will no doubt improve fuel flow, the crank also has a larger duration so it is open more for each revolution which will allow the engine to rev higher and utilise the larger ports on the sleeve.





Next we have the difference in the engine crankcase's, the .21 has alot more machining, they have also hardcoated the area's in which fuel flows up the inside of the case when a sleeve is fitted. Pictures are the best way to demostrate the difference.









The outside of the .21 engine is hardcoated, which will make it easy to clean and gives it a nicer finish. Comparing figures on the performance of the engine is also surprising, the .18 engines power begins at 6,500 rpm and is good until 32,000 rpm. The .21 starts at 6,000 rpm and is good until 35,000 rpm. So not only will it have alot more power, it will be on power at lower rpm's and will rev higher.

To wrap up the review, Infinity have not only built a .21 engine to fit into a 1/10 car, they have completely redesigned it so it will be a complete weapon, I mean if they just put a larger sleeve and longer conrod they would have a .21 engine that goes great and beats any .18, but by making all of these improvements they are ensuring that the power is going to be mindblowing in such a small car, even the new lightweight HSP 1/8 cars that have the .18 engine are going to be very quick with this .21 engine.

GREAT REVIEW TREV
can't wait for my infinity

Nice review Trev! If I was a Nitro guy I would be getting one of those puppies. What are they worth?

They are $119, extremely good value, I told a hobby shop about my prices and they said I should be selling it for alot more than that, I may put the price up by $20 if a few hobby shops start buying.

Great in-depth review, shows us what we want and need to see. Wish i had the cash for one of these.

I have more of these arriving Monday / Tuesday so they are available from my store here:

http://www.plaig.com.au/store/product_i ... cts_id=383