O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine

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O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
Price: $249.99
Discontinued Online
This item is discontinued and no longer available for purchase. You may want to search our site for a similar item.
This is the O.S. Max .21 VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine. Competitors tend to stick with a winner — and the .21 VZ-B V-Spec-T (P) makes that easy to do! Not to mention this engine won the 2006 IFMAR World Championships!

The raw power to exploit a split-second opportunity is there, tempered by the ability to fine-tune and finesse throttle control to the needs of different tracks and situations. And to help keep the .21 VZ-B V-Spec-T (P) at the peak of its power, O.S. has given it a billet aluminum piston, hardened ABC sleeve for added wear resistance and a new crankshaft design that's simultaneously slimmer and stronger than any O.S. crankshaft ever made. The .21 VZ-B V-Spec-T (P) — designed for first-place finishes over the long haul — from O.S.

This engine usually runs best in most conditions with the included OS P3 Turbo glow plug, however depending on the weather conditions the OS P6 plug can sometimes work better (usually in very humid or cold conditions). The best tuned pipe for this engine is the T-2050 tuned pipe, although the new OS T-2060 tuned pipe also works well. May be run with up to 30% nitro fuel without reshimming the engine, but an extra shim is included if you wish to add it to run 30% nitro fuel.
  • More power and durability. The brass sleeve is chrome-plated for performance and hardened to withstand the wear that racing action can produce. CAD-refined and CNC-machined ports smooth airflow and boost power.
  • Track-tune in seconds! Increase control on low-traction tracks by inserting the 8 mm (red) or 9 mm (blue) carb restrictor. Takes only a second, but pays off, lap after lap.
Features:
  • Hardened, chrome-plated, 4-port, cylinder and liner for high durability and long life
  • Machined steel piston features parallel rings that trap fuel oils and use them as a seal to enhance compression and boost power
  • Reshaped crankcase core ensures smoother air flow and more consistent performance
  • Slide Valve Carburetor with 8mm and 9mm Carb restrictors allow tuning to specific track conditions, Low-end Needle adjusts from side to side for maximum adjustment ease
  • V-shaped two-piece turbo head design provides fast heat dissipation
  • UPDATED: This is the updated engine with the new 21J carburetor.
Includes:
  • One .21 VZ-B V-Spec-T (P) racing engine w/21J carburetor
  • One P3 Ultra Hot Turbo plug
  • One instruction manual w/OS decal
  • One extra head shim/gasket(The other gasket is pre-installed)
  • One 8mm carb restrictor
  • One 9mm carb restrictor
  • One exhaust port seal ring
  • Two carb rubber gaskets
  • One carb cover
  • One exhaust cover

This product was added to our catalog on April 13, 2006

Anonymous
Friday, Nov 18 2011 (about 12 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
I too have had nothing but bad luck with these engines. After I got it broken in it was fantastic for about two gallons. After that it would only run till it got to around the 200 degree mark and would stall everytime. I thought it was something that I had done, so instead of getting a new piston/sleeve for it I bought a brand new engine. I installed a cooler glowplug and used 20% nitro instead of 30% hoping that it would make a difference. However, it started doing the same thing around the 2-2 1/2 gallon mark. Like alot of people have said before the O.S customer service didn't care and did nothing for me. i have been racing nitro for over ten years and have used many different engines but none did what these V-SPECS did. I have been running RB engines for the last 4 years and have had no problems. I am still running the first C6 I bought and it must have at least 10 gallons on it and it still has great compression. The funny thing is that the V-SPEC costs about the same and doesn't even last half what the RB's do.
Anonymous
Wednesday, Apr 6 2011 (about 12 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
i have 2 of os vzb v spec t and there great broke a piston after 25 ltr and the engine still goes hard there a great great engine
Anonymous
Verified Owner
Saturday, Jul 31 2010 (about 13 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
This is awesome engine!!! I use O.S T-2060 pipe and Werks Power Clutch with this and it works great in my CEN Matrix buggy
Anonymous
Verified Owner
Saturday, May 2 2009 (about 14 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
My beloved Vspec died at the top of the 5th gallon. I had it pinched to delay the cost of a rebuild or new engine. -//- As previously mentioned, I replaced the stock bearings with TKO ceramic bearings during the 2nd gallon of fuel. I am now on my fourth gallon, so I decided to replace the stock conrod [pin & "C" spring] with a Vspec "Speed" engine conrod. The stock bearings and conrod were performing without issue; however, I replaced them for added performance and confidence. The piston and sleeve has mild or slight resistance at TDC. The engine is making gobs of power. It's more than enough power for my [4348 grams] CEN truggy. I should also mention that thus far I've been running it with the stock [red] 8 mm carb restrictor. That restrictor easily yields 10-minute runs. Nonetheless, I installed the 7 mm "Ninja" restrictor today to reassure my confidence that I'll only need to make one pit stop during 20 min races [mains]. Having said all that, this is by far the best performing engine I've ever owned. The carb is also the friendliest and most forgiving I've ever had the pleasure to tune. I can't wait until the new Vspec is released. Just as this one did, when the time comes, it'll get TKO ceramic bearings and a new conrod [pin & spring] for added performance and confidence. You do that and these engines will perform even better than they do stock.

Cheers mates ;o) -//- In all fairness I have to add to my July 25th post regarding the rear bearing replacement issue. Shortly after replacing the stock bearing with a ceramic bearing, I discovered that the "engine chatter" was one of my clutch springs. IT WAS NOT THE STOCK BEARING IN THIS ENGINE. I should've posted here when I discovered the true issue, so excuse me on that.

I had planned to post an update at the end of the two or three gallon mark, however, I have yet to reach the end of the two gallon mark b/c I spent most of the second gallon trying to sort my back up engine. Needless to say, this past weekend, I ran my OS Vspec in my very first race ever. It ran flawlessly. I arrived with only a half hour before race start, but no problem, cos' it fired right up with " let's do this fool !!! " - I had no flame outs... not one. I leaned it a bit, but I really didn't have to. It was running fine from the start. This is an amazing engine.

My only issue with this engine is the price. It'd be more accessible if it was around the $200.00 to $250.00 price range, like the new Werks 5 port engine or RB Killer 9.

Note: My truggy weighs 4400 grams. However, the OS Vspec is more than enough power. -//- I'm at the 2 gallon mark. The stock rear bearing started to chatter, so I replaced it with a TKO ceramic bearing. The engine is running great again. Even though I had to replace the rear bearing at the two gallon mark, I am still going to rate this engine as good [five stars] b/c of it's friendly carb and jaw dropping power. -//- i was a bit apprehensive when i ordered this engine b/c the reviews are all over the map. however, the build of this engine looks clean and smart. in terms of tuning, it's extremely friendly... for that reason alone, i'd like to buy another one. i've barely gotten it broken in, so i can't offer any feedback on longevity. nonetheless, the pinch is almost as tight as axe rossi engines i've used in the past. i inspected the inside and it appears clean, simple and of good quality. i like the needles as well... they are placed well and seem to be easy to reach and adjust. i'm still running it somewhat rich, however the HP and acceleration is unlike any engine i've used [ready to run cen matrix tr arena engines, .26 sportwerks and .21 axe rossi]. i'm barely beyond break in, so i'm still taking it easy, however, here and there in the rough... a blip of the throttle and i'm effortlessly over obstacles. the power comes on smooth on the flats and straights... some say abrupt, but in my opinion, it comes on smooth and linear.

my last track outing was much more efficient and pleasurable. i was in and out in a couple of hours b/c i didn't have to troubleshoot and chase tunes all afternoon. i fired it up and ran it to my hearts content and left early, for once. it fires up, doesn't flame out, holds a tune and has the best powerband i've ever experienced.

if it will last five or six gallons [proper maintenance], it will be the primary brand i'll run. again, the experience has been so positive that i wish i had two of them to test. this engine is extremely friendly ;o) i will post back around three to five gallons.
Nicolas
Monday, Aug 3 2009 (about 14 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
Great engine! Got about 4 gallons on it at the moment and its running very strong. I use a P3 glowplug, JP-4 pipe and aluminum Dynamite Max Life clutch shoes with 1.1 springs. great powerband from bottom to top! Just be careful when tuning not to lean out the LSN too much! I wasnt getting a satisfactory tune and thought it was the LSN, NO, just be patient.
All in all great engine excellent performer! -//- Got about 2 gallons through this engine and it runs great! I did about 1/2 gallon of break in and havent had any problems at all. Easy to tune, VERY powerful in all RPM ranges and has excellent reliability.
Anonymous
Sunday, Apr 11 2010 (about 13 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
I HAVE ABOUT 10 GALLONS THROUGH ONE THAT I HAVE HAD FOR THREE YEARS AND ALL I HAVE DONE TO IT IS REPLACE THE FRONT SEALED BEARING AND HAVE IT PINCHED. STILL HAVE IT AND USE IT AS A BACKUP ENGINE. I THINK IT ALL BOILS DOWN TO BREAK-IN AND TAKING CARE OF IT. THESE LITTLE MOTORS WILL RUN WITH THE BEST OF THEM. OS ENGINES ROCK!!
GERARDO GONZALES
Monday, Oct 5 2009 (about 14 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
at first i had issues with this motor it lost its pinch 2 gallons into it. i decided to replace piston sleeve con rod and new ceramic bearings and on second gallon of 20% its keeping up with guys running v-specs on 30%. now this motor is awsome...hope it last longer than 2 gallons.
Anonymous
Verified Owner
Monday, Aug 3 2009 (about 14 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
Great Engine yes, but doesnt have the logevity the price warrants.
jeremy sorvino
Friday, Jul 31 2009 (about 14 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
This motor rocks never had a problem with mine and i had easy 10 + gallons over 3 race seasons
Jeff Allen
Sunday, Jul 12 2009 (about 14 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
I too have been racing a long time and have owned a lot of engines. ....but, I have to admit the V Spec is a workhorse motor. Yes, some people dont have very good experiences with this motor but most people love them. The OS Vspec didnt get to where it is today by being a bad engine. In my opinion, (remember, its my opinion) that most engines today, at any price, dont live as long as they should; considering the cost. This is primarily due to the abuse motors take today. Engines we use in 1/8 offroad take a beating; buggies and truggies are designed much stronger and will hold up to abuse that older buggies and monster trucks (before truggies) could take. Tracks are larger with bigger jumps, longer straights. Engines are lighter, thinner, but we expect more out of them as far as performance goes. This, I believe, contributes to the shorter life span. Most people I race with run their motors leaner because winning is so important; they'll sacrifice the life of the engine to win. If you want to compete, you have to do the same. All of this is good though; we push the manufacturers to make them better and stronger in the end; hopefully. I love the Vspec and will always have them in wait for the right tracks and conditions......New comers to racing would do well to own this motor as well as seasoned racers.
Anonymous
Saturday, Jul 4 2009 (about 14 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
Magic Motor.... Tight on run in... Tunes Nicely (When treated with respect)... If you have problems with one chances are its a lack of ability or basic maintenance rather than the unit... First and last motor "The Average Racer" should own... Not the most powerfull i've used but definatley given me the most satisfaction...Easier to get consistent "longer" run times when compared to other units i've owned..
Overall though to get a more powerfull unit i would only use the new Allum Black head O.s,
Fuel Economy vzb wins though
Anonymous
Wednesday, Jun 24 2009 (about 14 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
These are good engines, if you take care of them-i.e. getting temps up to 220 for break in, try not to run the engine over 260 (because the sleeve expands more than most engines and that is why it looses compression instantly), run a good smooth clutch/gearing combo coupled with the right pipe, and it will last. I would suggest changing the rod to a Speed rod at the 3-4 gallon mark (you should do this on all engines) and changing the bearings to TKO ceramics at the same time. I have about 3/4 of a gallon on my V-Spec (Byron Race 20% 8 tanks for breakin, and Byron Pro driver 30% for racing). For break in I ran half a tank at idle, then let cool for 15 minutes. Finish the tank off at idle blipping the throttle to get rpm's up a bit then let cool. I do a longer break in process than otheres (start racing tuning at about 1/2-3/4 of a gallon) but in the end it pays off. I have also heard by some engine modders that quick breakin can cause bearing failure (balls not seated in properly) and the engine not having as much compression. Quick questions though.....I was tuning this engine at the track and the track owner (who's son is a factory driver for OS) set my MSN at the 2 o'clock position. This is 1/4 of a turn leaner than factory settings (10 oclock). But it hauls bottom to top and temps ranged from 204-215 throughtout the night. I shouldn't be worried should I? Also, is there anything I can do to to get the idle down after WOT quicker? There is a long straight then a short jump so you have to slow down fast, and the engine idles fairly high when I brake. Any suggestions? I give it a 4 just because its history of bearings failure, cracked cases (both from the older models), and losing compression instantly.
Anonymous
Monday, Jun 15 2009 (about 14 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
one of the best motors ive ever ran. but they dont last past 3-4 gallons.
zeke ballinger
Tuesday, Apr 21 2009 (about 14 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
OK SO IM ABOUT 6 FULL GALLONS IN, BOTH ENGINES ARE STILL THE FASTEST IVE SEEN, THE .21 IN THE TRUGGY STILL OUT FLYS ANY OF THE HUGE JUMPS WE HAVE -//- i currently run one in my rc8 and rc8t, way more than enough power, almost too much for beginning drivers, i run the os 2060 pipe and is getting 9-10 minutes in the buggy, and almost 13 minutes of run time on a 90 percent tunned motor, it holds a tune great. ive had 0 problems with this engine. i will say they only last as long as you want them too, you treat them bad, run them hot, no afterrun they will wear out, if you treat them good they run like rapped apes 2 gallons in and counting
Anonymous
Thursday, May 14 2009 (about 14 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
I've owned RB, Go-Tech, and O.S. V-Spec engines... in that order. The RB and Go-Tech engines were fine (no real complaints from me), but the V-Spec is all I use now. I own four of them, all in various degrees of use, and they all stay in tune and run more consistently than the RB and Go-Tech engines I used in the past.

I plan to stay with O.S. for a long time.

NOTE: There are several complaints about O.S. engines ("they don't last") across the various R/C forums. There are two things to consider: a) O.S. sells a lot of these engines and b) upset people are 100x louder than those who have a good experience with a product. Factor those two facts together and the number of negative end-user reviews and the ratio of negative:positive makes sense.
Anonymous
Monday, Mar 16 2009 (about 15 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
I had bought this motor off of a guy at my local track I had about 3 gallons on it aand the first time I put it in my truggy I fryed my servo and the truggy ran a way and it kill the motor. I took it apart and put some ceramic bearings in it and repinch it and man does it fly now way faster an my trinity Draked.
Anonymous
Tuesday, Feb 17 2009 (about 15 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
it took over 20 gallons 30% jac fuel to kill my v-spec,the compression was low,however it was the bearings that needed too be replaced.put back together with new bearings and seems to be just fine
Thamer Alhwairini
Saturday, Feb 14 2009 (about 15 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
This is good Engine
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
I love it
Anonymous
Friday, Feb 13 2009 (about 15 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
I have an EB Mod V-Spec, and it is a very fast motor. However I would never recommend them to anone that pays for their own engines. This is no fault of the work EB does. It surely performs. This engine is built with great precision and performance, but absolutely NO quality from OS. The materials of the crank and piston / sleve are very low and the engines are probably truly only good for one major event (less then 3 gallons at most). If you can afford to buy a new motor that often, go for it, but I'm going back to Italian motors.
Anonymous
Thursday, Feb 12 2009 (about 15 years ago)
O.S. Max 21VZ-B V-Spec-T (P) Off-Road Competition Buggy Engine
How much gallons need this engine to repair piston and sleeve???