813 27.2 ported

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hamster huey

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I built my first engine! Ive done lots of head kits but this was my first build. I got a new crankcase w/ bearings + seals, lightened and releived piston, new +2mm stuffed crank, new ONB ported head, 813 carb. I added the Zrc carb spacer, HPI filter, and side dom I already had. I use the hitec 5625 rated for .14 so it gives pretty quick throttle response. I love this setup! I only ran 3/4 of a tank on easy and it still broke the tires free on dirt with 1/4 throttle! I cant wait to fully break it in and get on it! It gets on the pipe so fast! It was a female dog to get started the first time as are most new headkits. It was scary at first it ideled up and down, wouldnt run, then after a few starts it found a idle! The 813 is easy to start as well. 3 pumps 2 pulls and go! After I was done I retorqued the head bolts, retorqued the exhaust bolts and pulled the plug to peek into the chamber. It all looks good so far. I still cant beleive how fast it revs and how quick it gets on the pipe. Now I gotta put together my V3 ported, lightened and relieved, 28.5 and pick up another 813. Thank you Yolanda and Fastlane for getting me into the 27.2.


One odd thing: my 813 is running best so far on 1.5h, 1.5l. Thats also when I started seeing some smoke out the pipe. How come on all my 1/5 when I set my carbs to stock settings I never get smoke?
 
nice job on the build. why do love the 27.2. i want to build my first engine but look at all the choices. where did you get the kit?
 
I saw vids of 27.2s and I like how fast they accelerate and the RPM they make. I went with a releived piston bc I had a few unreleived ones that expanded on different engines gouging the cylinder. I went with ported cylinder and lightened piston to try and get the most (in my price range) out of it. I have tried 2 carbs on it so far. The 813 mentioned above and the 668. Both have 2 to 5 hours richer on the H and L. The stock settings on either carb were too lean and it wouldnt run right. At first I thought that was odd but my theory is if its ported its moving more air, so its needs more fuel (more fuel+more air = more power).
 
I got the Oneill brothers racing 2 bolt race ported 27.2 and the lightened and releived piston and the cy wrist pin bearing all from oneill brothers racing. I also put new bearings in the crank case. They have them in 2 bolt and 4 bolt.


I would have got a 30.5 but alot of people start breaking drivetrain parts with the 30.5. My race ported 27.2 has enough power to break traction on all 4 bow ties on aspahlt or dirt and lots of top end- with either carb 668 or 813. It has so much power I drive 3/4 or less throttle most of the time.
 
Hey nice build, can't wait to try one myself! If you don't mind, what is the build going to cost? It's all the rapid elevation change out there in kansas that's screwing with yer needles haha :)
 
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ONB 27.2 2 bolt race ported head and stuffed +2mm stroker crank $149


CY gasket set $8


Crank bearings $15-40 (your choice)


Instead of crank bearings you could also get the crankcase that comes with bearings $45 (optional)


flywheel puller $13.50


piston stopper $9


relieved piston $+5?


I think that was it.
 
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The 27.2 is my fav motor I run a ESP in my MCD Race Runner and a ADA in my Baja will also be putting the same in my Ramp when its finnished. They have all the advantages of the strocker motors with increased tourque but they still rev like a 26cc. I have stitched up many a 30.5cc powered cars with my 27.2cc. Great choice you made mate and well done on your first motor build it usally turns out to be a lot easyer than you think hey.
 
In my truugy I prefer the 30.5 just because it weighs so much. All that extra torque is needed :)
 
Its all situational. In a lighter Baja a 27.2 will scream, and will outrev a 30.5. In a full aluminum Rampage MT the extra torque of the 30.5 will be better.
 
what will go better guys like faster and more power i want an overall engine. Should i get a 30.5 or the 28.5. Either i get will be fullly modded and ported thanks
 
I don't run big bore motors but I would suggest a Oneill Brothers's 30.5 all the way for the heavy rampage. That motor is a freaking beast.


P.S. As soon as the new XT comes out you might wanna go back to a 26-27cc. The car is so light I might even try a ported 23cc with a torque pipe like the side VRC for the MCD. I guarantee that setup will fly.
 
i just put the 25.4 4 bolt in my mt going to try and wear it out before i put the 4 bolt 27.2 in it runs very well fore a small bore motor 8 tanks through it and still ticking,
 
guys can any of you tell me wich one of the big bore kits fits the stock engine that comes on the redcat rampage MT?


i got the 26cc engine whatever it is, HY i think don't know!


thanks guys
 
Measure the outer diameter of the cylinder head skirts and see if it's a 38mm or 4mm skirt. This will tell you what head you can run.
 
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