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RB Concepts TM968

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M

Mondo

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Hi guys,

I just bought myself the RB Concepts TM928 7 Port .28 engine for my CRT
The engine's been fitted but I haven't run it yet. Before I do, I was just wondering if any Members have had any experience with this engine?
 
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Make sure you wear a belt, because this thing will pull your pants right off! All 3 of rb's.28s are insane. Each one stronger then the next, and you've got the beast. Take your time breaking it in, as with all rb's they only seen to be fully broken in around 1 gallon. So don't get frustrated if you can't run it the way you want it. It will definatly wake up at the gallon mark.

have fun with it!
 
Oops

vbgagnon

So, I kind of got myself a handful here huh?
The break in begins this weekend, some people/friends doubted my sanity when spending that much hard earned cash on an engine.
I'm a bit of an RB Concepts fan, so it was the logical choice instead of the more popular VTEC/STS/Force type big blocks

Thanks for the "warning" I'll be sure to tighten my belt up a notch or two before running "the beast"
 
These things are the seriuous motor to beat on the track, allthough I would have to question putting it in anything but an LSP--lol J/K My buddy ran one in his Kyosho conversion and it tore that Truggy up, shreaded a ton of parts, stock up on clutch bearings, go to Avid and buy them by the dozen--lol it eats them up pretty fast. It also tore up outdrives and other driveline parts. This thing has so much power he had a hard time keeping the chassis from flexing so bad it would eat up the clutch bell and bearings in a 5 minute heat...
 
If it tore up clutch bearings there was a problem with something. I would say slippage. YOur going the have to play with different clutches to get the right acceleration that you want.
 
Nah the problem was all in the chassis flex, it would twist it like a pretzel till the bearings got hot and wore out along with the bell, he tried EVERY possible clutch combo he could including a Fironi..he acually ended up selling it and going with a RB S7II. I mean it was some SERIOUS TWIST!!!!just put too much pressure on the bell!
 
Tm 968

This engine is fitted into my Jammin' X1-CRT which has a pretty serious chassis that is very wide and up to the task of most big blocks.
I've also fitted the Z-Brace to the chassis in anticipation of the flex

 
Combo

Revo Rancher

Thanks and I will do, if the weather holds up I'll put a few tanks through that bad boy over the weekend
Rest assured I'll keep you updated via this Thread
 
Maiden run....

Took the CRT with the RB 968 for a one tank maiden run today
Starting was fun, even with the plug a little loose, but the starter box never had an issue once the engine turned
On factory it was super rich, but once it was hot it ran like a babe, got a tank thru it without a cut out or stall.
Sounds so very different to the RB S7-II engine who's sound I am quite accustomed to
It began to rain, so I BDC'ed the piston and put the beast to rest until tomorrow when I will get a few tanks thru it
 
928 not 968!

I've put more tanks thru the big bad RB928 and all I can say is wooooooah!
As I was warned by vbgagnon this is a mofo engine! I've done half a dozen tanks and this beast is starting to show its true colors
I never thought I'd see the day that a Truggy with center diff would wheelie from a standing start. When I hit the throttle, the front tires lose traction, balloon and this launches the CRT into a wheelie!
What I can't believe is how quick the TM928 revs for a .28 and it's pure power across the entire rev range. I am stillrunning the restrictor in the engine and may remove it once I got a few more tanks thru the beast



To help with top end I've fitted a Vantage carbon dual chamber pipe.
 
I run a 928 in my CRT. Mine ran extremely well until last week at the IWC in Alabama and all of a sudden the thing got real phat and the temps dropped to under 200. I ended up going almost another half turn in on the high side before it ran clean again. It is almost unbelievable how much more power it has now. Did I mention it was at almost exactly a gallon when this happened? If you think it rips now just wait till it breaks in good! Beast is an understatement!


I have found the RB 9886 (OFNA 086) smoothed the power out tremendously and really made it more driveable. It helped make it possible to utilize the brutal power of this mill. I now have a JP1 and JP2 in my box. Just can't bring myself to go back after trying the 86.

Oh yeah....I love this mill too!
 
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Tm928

StaticSag

Thanks for the heads up on that. Very useful information. I know RB's just love to run lean and hot. I have a S7-II in my buggy ands that impresses me everty time I fire it up and blip the throttle. This was a deciding factor on the choice of engine for the CRT. There are so many .28's available nowday, I have no regrets paying up to three times more than a budget "bowl of rice" .28 from the Mainland costs.

Are you still running the venturi restrictor in your 928?
I'll see how the Vantage holds up, as I plan on racing this, I may look at a pipe that offers economy as I need a tank to last at least 5 minutes, if not longer for the (probably F) mains. I know the 928 should do this once fully broken in.
StaticSag, what's your average runtime per tank now?
 
Mondo said:
StaticSag

I know RB's just love to run lean and hot. I StaticSag, what's your average runtime per tank now?
Click to expand...


Mondo what would you consider hot? My rb 323 has not yet hit the 1 gallon mark yet and I love it still
 
RB Engines

Tighty Whitey said:
Mondo what would you consider hot? My rb 323 has not yet hit the 1 gallon mark yet and I love it still
Click to expand...

Without straying too much from the Topic at hand, namely the TM928, I run an S7-II in my buggy.
The S7-II tends to run nicely in the upper 290's and in race conditions, I've seen over 310° one of the guys I pit for without any fuss and a sub 7 minute run on a regulation 125ml buggy tank in A Main race conditions.

Back on Topic:

The 928 ran at just over 220° on its 6th break in tank, so I've put under a quarter of a gallon thru this engine and the temps are good. As it breaks in it will be leaned out and if I see the engine run in the 275°-295° range I wouldn't be too concerned. Compared to some engines, that is a hot temperature.
I do have a range of Turbo Glowplugs: 5, 6 & 7. The TM928 comes with a 6 as standard, StaticSag what glows are you running?
 
Hi guys, I have an old two motor starterbox that I use two 7.2v stick packs in, I think it's a dynamite....would it turn over one of these engines? I am thinking of getting a upgrade engine for a rtr crt, maybe this is the one? Just not sure the starterbox I have would be up to the task.
 
Starting the 928

Hudler,

I use the LRP Competition starter box with 2 x 7.2V packs.
It works fine as long as you loosen the glowplug a little to help reduce compression.
Another thing is the CRT has a real wide chassis, so it's not suited to all starter boxes like my TTR starter box for example
The LRP starter box is set up with the CRT's chassis slightly biased to one side to line the flywheel
 
Hmm, now how much more power does this have over the 728? I've read this engine is to make a comeback of the STS .28 cuz that mill can eat up 728s :D
 
Tm928

You cannot compare the cheap and cheerful STS .28 engine to any brand name big block, never mind the RB TM series engines!
The fundimental difference between a 728 and 928 is the 728 has 5+2 ports and can be pullstarted and the 928 has 7+2 ports and is starterbox orientated.

Sure the the STS engines fly but they are not all that quick and they last for about 4 gallons of fuel then begin wearing out. Let's compare apples with apples here.. you cannot compare a bowl of rice $150 STS engine to a quality $400+ RB mill..

My TM928 has had just under half a gallon thru and it is flying. The Jammin' CRT is an animal when armed with an RB TM928!, even with a center diff the front wheels are always airborne. The CRT's tires balloon like mad, so I need to strap the inserts on the next set of wheels/tires I mount for the CRT
In the end I had to richen the HSN out a little to keep the CRT's nose planted. This engine impresses and I know there's more to come from it.
I've fitted a Vantage carbon dual chamber pipe to the TM928 and on track the natural big block torque is complimented with an awesome mid range and potent top end.

Click me to see this photo
 

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