T-Maxx big block build

[RyanKeith78]

Hello, hope someone out there can point me in the right direction. I'm building a big block Tmax 3.3 using a stock extended chassis, I have everything mounted using a Big Red .28, however, I m lost on a manifold to use that curve over the shock tower as the stock one for a big block. Do they make a Tmax big block manifold so I don't have to hack anything? Would the O.S .21tm manifold work on the big red?

 

[olds97_lss]

Hello, hope someone out there can point me in the right direction. I'm building a big block Tmax 3.3 using a stock extended chassis, I have everything mounted using a Big Red .28, however, I m lost on a manifold to use that curve over the shock tower as the stock one for a big block. Do they make a Tmax big block manifold so I don't have to hack anything? Would the O.S .21tm manifold work on the big red?

No. The OS21TM manifold is pretty much the same ID as a proper 1/10th manifold.

3.3 -> 21TM -> 18TM

Got any photo's of your engine installed to show what you have to work with? I had a BB maxx many years ago. Didn't use a stock chassis though, I had an XTM conversion and a buddy had the Dynamite conversion. His was made from better stuff.

RB Concept made a header/pipe for their drop in TM323 and TM523 (I think that was the engine names), but I'm not 100% sure it was "big block" ID. Kind of looks like it was.

Not sure you can find one though.

 

[cbaker65]

That almost looks like the Ae. side header conversion for the MGT. .but turned upside down!...

 

[olds97_lss]

That almost looks like the Ae. side header conversion for the MGT. .but turned upside down!...

Yeah, that might work, if you get creative with the connector/coupler. Like one of those OFNA 90 couplers they used on short headers. Looks like HPI had one, but I think it's too small ID:
https://www.amainhobbies.com/hpi-12x30mm-silicone-exhaust-coupling-purple-hpi87057/p183754

MGT header:
http://rover.ebay.com/rover/1/711-5...0001&campid=5336250976&icep_item=123456565582

You'd need to make your own ring to connect springs to, I can't find it on it's own:
https://www.teamassociated.com/parts/details/25426-ASC25426-mgt_4_60se_exhaust_manifold/

Also, not sure that header will work, but it's probably close to working, if your gentle and bend it a bit.

 

[RyanKeith78]

No. The OS21TM manifold is pretty much the same ID as a proper 1/10th manifold.

3.3 -> 21TM -> 18TM

Got any photo's of your engine installed to show what you have to work with? I had a BB maxx many years ago. Didn't use a stock chassis though, I had an XTM conversion and a buddy had the Dynamite conversion. His was made from better stuff.

RB Concept made a header/pipe for their drop in TM323 and TM523 (I think that was the engine names), but I'm not 100% sure it was "big block" ID. Kind of looks like it was.

Not sure you can find one though.

Here's a pick of my stock tmax chassis big block build. As u can see, think I'm going to have to use a savage manifold, used spacers to move the shock tower back enough for clearance, moved the trans up a notch, still have the stock 1/10 scale clutch and spur, but have the 1/8 scale set up on the way.

 

[olds97_lss]

Here's a pick of my stock tmax chassis big block build. As u can see, think I'm going to have to use a savage manifold, used spacers to move the shock tower back enough for clearance, moved the trans up a notch, still have the stock 1/10 scale clutch and spur, but have the 1/8 scale set up on the way.

What engine mount is that? The 1/8 clutch/bell is going to eat up even more room, fyi. Another 3-5mm. May have to get creative there too.

Would be easiest if you ditched the 8 shock setup and ran a 4 shock setup. Find some 1/8th buggy shocks that are close enough in length and only run them on the back side of the tower.

What shocks are you running? Not sure I've seen those before.

 

[RyanKeith78]

The mount is the ofna picco, for the .26 tmax. Good idea on the shocks, think that's what I'll do. Them shocks are the Gmade rebound.

 

[D3MON]

the build looks really good, really want to see more. only problem i can see being single shocked is the weight of the truck. being all alu. like that. it may be me over thinking it though tbh. will have to say the only thing i don't particularly like on the T-Maxx trucks is the engine running parallel with the truck, so much length between engine and transmission mounts. easy to strip spurs during flexing. though yours being solid aluminum that shouldn't be an issue.

 

[olds97_lss]

the build looks really good, really want to see more. only problem i can see being single shocked is the weight of the truck. being all alu. like that. it may be me over thinking it though tbh. will have to say the only thing i don't particularly like on the T-Maxx trucks is the engine running parallel with the truck, so much length between engine and transmission mounts. easy to strip spurs during flexing. though yours being solid aluminum that shouldn't be an issue.

I ran a 4 shock setup on my big block converted maxx back in the day. I used Unlimited Engineering Supermaxx shocks, which were modified OFNA 9.5 buggy shocks that were shorter than rear buggy and longer than front.

As for flex, that section of the chassis doesn't really flex if you have alloy chassis rails underneath. Well, my BB maxx had an alloy transmission, alloy chassis rails, RC Solutions spring steel skids, alloy bulks. So the entire core of the truck was like a brick. I ran RPM arms, carriers and towers.

The main issue back then was the cvd's didn't hold up (I had XTM conversion) and the diffs didn't hold up. Even with a mild big block, the diffs would grenade after a few bash sessions.

These were 2 of mine and my buddies:

His was the blue flames body. Had the dynamite BB conversion and a Powerhouse .26 big block. He had traxxas big bores. The GTR's didn't exist yet. He may have had Integy MSR's on it at the time of that photo, he busted almost all 8 of them on the first or second bash then went with the big bores.
The middle half bodied one was mine with the supermaxx shocks with the XTM BB conversion and an Omega Picco 21 big block.
The other on the end was just my other t-maxx with an OS15CV-R(X) in it.

Even with the BB conversion, there was barely enough room for the shock behind the header:

Here's a photo of one I found on the internet a year or so ago that shows a pretty much stock maxx with the xtm conversion on it:

 

[D3MON]

Olds... you are making me miss my old 2.5 T-maxx even more with those photos, mine went a different direction though. had the O.S. .18 CV-R engine in it. mine had plastic rails as the only ones i had access to at the time were integy and that was the timeframe that they were hit and miss for quality (as always looked good though), and i didnt want to fork that kind of money over for a miss especially being 13 or so. i got lucky with mine as it so happened that it was the LHS owners truck (funny story with that) and it had the pro-line powerstroke shocks.
i do remember the center shafts being the weak point on mine. diffs didnt explode on me but not as much torque with that motor.

 

[olds97_lss]

Olds... you are making me miss my old 2.5 T-maxx even more with those photos, mine went a different direction though. had the O.S. .18 CV-R engine in it. mine had plastic rails as the only ones i had access to at the time were integy and that was the timeframe that they were hit and miss for quality (as always looked good though), and i didnt want to fork that kind of money over for a miss especially being 13 or so. i got lucky with mine as it so happened that it was the LHS owners truck (funny story with that) and it had the pro-line powerstroke shocks.
i do remember the center shafts being the weak point on mine. diffs didnt explode on me but not as much torque with that motor.

That engine came out quite a while after I got rid of my maxxes or I would have ran that. By the time that came out, I can't remember what all I had, but I did have a HPI NitroMT which was the predecessor to the MT2. It came with a nasty little single needle 15 in it that was on it's last leg. I put one of the 18cv-r's in it because I had run the 15 cv-r's for years in my maxx and xxx-nt. Figured more power with the quality of an OS, couldn't hurt!

The diffs on my small maxx held up ok. I ran an orion .18 in it. Back then, there was an Epic 18, fantom 18, orion 18. I don't think OS had anything but the .15 at the time. Years later I had a revo and got a 18TM. That was a screamer. I still have that engine somewhere and still out performs the 3.3's I tried. Just not enough oomph for a 3.3 chassis revo though, and I put an OS21TM in it... and I have a big block revo with an LRP28. lol!

Clearly, I was never happy with the power traxxas was giving.

Now that the 3.3 is out and I have one in a drawer along with a 18TM... makes me think of picking up a 3.3 maxx roller... but I ran out of shelf space and storage space for parts support.

 

[D3MON]

lol, that .18 cr-v was plenty for that max, not tons of torque, but man that thing had some legs to the power band. it was perfect for me because i wasn't as much into the wheelies, and just loved going fast and launching jumps. if i remember correctly the TM and the TZs were more geared for the low end. am glad that mine went to my brother to run it though.

 

[olds97_lss]

lol, that .18 cr-v was plenty for that max, not tons of torque, but man that thing had some legs to the power band. it was perfect for me because i wasn't as much into the wheelies, and just loved going fast and launching jumps. if i remember correctly the TM and the TZs were more geared for the low end. am glad that mine went to my brother to run it though.

Really, they had power all over the place, but they would wrap out to some pretty high RPM's. The TZ especially. Pricey engines though.

Until I bought my OS21TM, the OS18TM was the most expensive engine I purchased. I think I paid $210 for it in 2006. I probably put at least 10 gallons through that thing over the years. I ran it in my jato before converting it to electric. Busted 3 or 4 crank cases from landing jumps so hard. After the last time, crank cases were hard to come by, so I put a 2.5R in it and poached the carb from the 18TM so I could get it to hold a tune.

Back when she was shiny and bright:

And here, almost 10 years later in 2015 when I got the 21TM for my second... 3rd revo:

I gave up on the revo after getting the 18TM, then tried my hand at putting a big block in it. Got tired of tweaking the chassis all the time and breaking shocks/pushrods constantly. Got rid of it in 2007, kept the engine and BB conversion... then in 2010, got a slayer... the converted it to a 3.3 chassis big block revo and fully committed to it. Got GTR hard anno'd shocks, VDK in them, M2C chassis brace, proper roll bar and was finally able to keep the thing from grenading. Then got another one used, did all the same structural upgrades, but wanted to keep it a small block and try the 3.3 out since I never had. It came with it. Ran like garbage, so bought a new 3.3... also hated it. got the ths pipe, still not great. Got the 21TM, and then it was fun to drive finally. Now it's the most expensive engine I ever bought.

Wow... really went off the rails there.

Sorry OP.

 

[johnnydmd]

Ryan, is that a 3.3 trans? Just wondering if that's a direct bolt in for the 2.5 chassis, or do you need to get different/modified center shafts?

Sweet looking build, following

 

[Rc bibifi]

No. The OS21TM manifold is pretty much the same ID as a proper 1/10th manifold.

3.3 -> 21TM -> 18TM

Got any photo's of your engine installed to show what you have to work with? I had a BB maxx many years ago. Didn't use a stock chassis though, I had an XTM conversion and a buddy had the Dynamite conversion. His was made from better stuff.

RB Concept made a header/pipe for their drop in TM323 and TM523 (I think that was the engine names), but I'm not 100% sure it was "big block" ID. Kind of looks like it was.

Not sure you can find one though.

What clutch setup are you running ?

 

[olds97_lss]

Pretty sure it's dynamite max life alloy 2 shoe. Can't really find them anymore.
https://www.amainhobbies.com/dynamite-maxlife-traxxas-clutch-shoe-spring-set-dynp5184/p25535