Dynamite Mach .28 Big Block Installation

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Traijin

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I purchased a true big block to replace the Picco .26 that had run its course. I have a THS pipe that was originally on the Picco, but I see the diameter of the exhaust port on the .28 is significantly larger than that of a 3.3 or a Picco .26. I do have the Big Block installation kit, but I don't see how the header can attach to a THS pipe. The THS is spring held with 3 small springs attaching the header to the pipe. The Traxxas header has no flange or provisions to be spring held. I did leave a message at THS to see if they offer any large diameter header solutions, but I have not heard anything yet. Anyone out there know if I can get a header that will mate with Mach .28 and a THS pipe while retaining the stock Revo pipe location?

Thanks
 
The only one I knew of that may work would be the trinity hi-flow revo pipe. It came with two headers, one for small blocks and one for big blocks. I think the small block one was specifically for TRX engines though.
 
I did get a reply from THS late last night. Looks like my question may have prompted them to change up their home page a little. Now they display a new REVO pipe for big blocks as a "Latest Release" So the short of it is, I need a new pipe or I will be constricting the exhaust... I need to spend another 60.00. Which puts me significantly more expensive than just replacing the Picco .26. Bah, live and learn.

Picco .26 Approx 210.00


Big Red 150.00
Big Block Install Kit 40.00
New THS Pipe/header 60.00
Total 250.00

Ohh well, at least it will look neat, and the is no replacement for displacement.
 
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you could probably sell your THS pipe and the picco if it can be rebuilt.

just a thought!
 
Adding the big block project just got more complicated. I had to fabricate an extension plate for the throttle bell crank mount bar to create the proper geometry for throttle operation. Not too bad, some nuts and bolts and sheet metal... works like a charm now. Then I tried to mount the motor into the chassis. The back plate recoil starter hits both the upper A-arm and the rocker. The only solution I can come up with is a blank backer plate and buy a bump starter. So, now I found an OFNA starter box for around 60.00 and a backplate for 12.00.

so there goes another 72.00... I am going to gear this thing to hit crazy high speeds just so I know I am getting something special.

Traijin
 
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You'd probably be better off leaving the gearing close to stock for break-in. That would make for a little less load while the engine is tight.
 
What BB kit are you using? New era has one that would let you drop any typical BB in there. Dubbed as the "leaner" mount.
 
I am using the Traxxas big block mount. Prior to purchasing the Taxxas unit I looked up both New Era and Qoncepts as possibilities for mounts, but it looks like both of them raise the engine up, thereby raising the center of gravity. My judgement was to run with the stock engine mount height and change the engine dimensions to fit. I also found the Qoncept mount to be unavailable and to be honest, the New Era web site is not impressive. The products are not well described and their application are not clear. So this is the path I chose.

Traijin
 
Yeah, the new era one does raise the engine, but it does also work with pretty much any BB. Well built too. Wish they made the cradle that the mount sits in, but they don't.
 
Got the back plate and starter last night. I had to pull the crank shaft and grind the nib that the recoil starter has purchase on. Not a difficult operation... just careful dremel work. Reassembled to motor with the new back plate and mounted it up. I fired the engine last night, ran like a top... except very rich. So much so that combined with the cold weather the piston kept loading up and stalling the motor after it had run for awhile. The forecast for this weekend id 50 degrees and rising so I expect to be able to run a full break-in this weekend.

I love the placement of the carburetor, on the Picco max, the air cleaner horn barley clears the spur gear. With the Big Red, I have plenty of room between the horn and spur. So I finely took some pictures of my rig.

This started as a beat up machine bought off Ebay. It was a 2.5. Parts I have Changed:

3.3 Chassis
GT Shocks
Aluminum Push Rods and Turn Buckles
Traxxas CVDs
RPM True True Track
RPM Front A Arms
Forward Only Conversion
Center Differential
Rear Brake
P2 Rockers
Sway Bar Kit
Water Proof Digital Servos for Throttle and Steering
Traxxas Wing
Platinum Style Servo and Rx Boxes
E Revo Bumpers
Motor Saver Air Cleaner
THS Pipe (Will be Changed to Big Block Pipe from THS)
Traxxas Big Block Mount
Belted Proline Bow Ties
New front and back Bulkheads
New Traxxas Center Drive Shafts


The Only original parts are the front shell of the transmission, beadlock wheels and the fuel tank.

DSC04237.jpg


DSC04233.jpg


DSC04234.jpg


DSC04235.jpg

Here is the Bracket I had to make. Not pretty, but functional none the less.

DSC04236.jpg
 
I purchased a true big block to replace the Picco .26 that had run its course. I have a THS pipe that was originally on the Picco, but I see the diameter of the exhaust port on the .28 is significantly larger than that of a 3.3 or a Picco .26. I do have the Big Block installation kit, but I don't see how the header can attach to a THS pipe. The THS is spring held with 3 small springs attaching the header to the pipe. The Traxxas header has no flange or provisions to be spring held. I did leave a message at THS to see if they offer any large diameter header solutions, but I have not heard anything yet. Anyone out there know if I can get a header that will mate with Mach .28 and a THS pipe while retaining the stock Revo pipe location?

Thanks
Yes the ths 146 I have it on my revo with an os .21 tm max and it a great pipe it darn sure brought my os to life very noticeable difference
 
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