Super Jet bpipe boreing

The Penguin

triple secret probation
How much of a difference does this produce?
X-scream bored one out for me.

it's on a 61x/61x with the b-pipe, ADA head, wetjet intake, a modded rev limiter and lightened flywheel.

I think hits better than my 62t cased/ported 61x cylinder with ADA head, stock b-pipe, MSD, and lightened flywheel.

but that's just me. it's probably also tuned better than my 62T motor.
 

BruceSki

Formerly Motoman25
Location
Long Island
I was running a stock b pipe.(46mm) I opened it up to 48-49 and ran it on the same motor without my TBM flywheel. It actually pulls harder after that even though I gained weight swapping back to a stock flywheel.

I have it out to 48-49 on my .50 over Xscream ported 701.
I have it out to 51-52 on my SS865.

Its cheap power and easy to do if you have the right tools and time to kill in the winter. I used my 90 degree air tool with something similar to those rasps. They did the job to a rough finish in about 20 minutes for both the headpipe and the manifold. I cleaned the headpipe and mani up a bit with a sanding drum on the dremel to finish it off.

I didn't go nuts and polish it to a mirror finish because I think it's a waste of time. The carbon buildup will smooth out any minor imperfections within a couple gallons of riding.
 

Waternut

Customizing addict
Location
Macon, GA
You mean a rasp?

Anybody use something like this? http://www.harborfreight.com/5-piece-rotary-rasp-file-set-4476.html

With a steady hand you could get the bulk of material removed quick then just have to take the time clean up. Of course chit can get out of hand real quick too.

Yes I used a curved hand rasp. Those rasp bits may work and for the price it'd be worth a shot. However, I have a bit like #115 in this picture and it clogs up almost instantly when I use it to grind on aluminum.
 

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OCD Solutions

Original, Clean and Dependable Solutions
Location
Rentz, GA
I use a CP 90deg mini die grinder and one of these for most of my grinding work. It's a carbide bull nose. Yes, it galls up pretty quick on aluminum but lube helps and a pick works well to clean it every couple of minutes of use.

ballnosestan.jpg
 

#ZERO

Beach Bum
Location
Florida - U.S.A.
I don't know if this will work or not. But there's a guy her in town that does al fabrication and he uses bar soap on his grinder wheels / bits. Has anybody tried it on bits? Kind of random I know... Just curious.
Yes... wax you're carbide burrs so they don't load up with aluminum.

The exhaust manifold should be bored out using a mill for accuracy so you don't hit the water jacket area and a 2-inch coarse flap wheels works well for porting deep inside the head pipe where most the restriction is located.
 
kenny,wouldnt waste time on a bit that wasnt a good carbide,fasten-all and mcmaster both sell really nice bits for cheap,one good large diameter 1/4 shank bit with a slight conical shape rips through this job with a little wd40 and doesnt clog the deeper grooves in aggressive size bits.

zero,what kinda wax you talkin bout,ive always just used wd40

alex,its a worthwhile mod,I got a little extra power outa my motor,the bpipe was designed around a stock 701,when cc increases are made,or more freeflowing porting is done in cases and cylinder more flow is needed through exh.not sure how a stock octane motor would do with a larger bpipe though
 
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Had mine done by the shop that ported my engine, they really preached about that being a major part of the port job.
I was also recommended by the same shop to start fresh with a newer gen headpipe. He told me the older ones were cast thinner and that you didn't have as much material before cutting into the water jackets. He said he couldn't open my headpipe as far as he wanted with the old one. It was good advice, found that my old headpipe had a small crack in the inner jacket very shortly after I ordered the new one and had it ported. I had also just spent a nice chunk getting the adj screws free'd up on that old POS headpipe. Major waste of money.
 

QuickMick

API 1104 AWS CWI
Site Supporter
If this helps, there are double cut deburr bits are made specifically for removing aluminum that will not gaul up. The single cut deburr bits can gaul up quick. Same for the sanding drums and grinding disks that are made specifically for aluminum.
 

swapmeet

Brotastic
Location
Arlington TX
Good stuff d-moss...

So, i'm still not clear on weather all headpipes and mani's are the same concerning how big you can go, I didn't want to go too far so I checked up at 48-ish on mine. It took a lot longer than 20 min but i'm pretty happy with the results.

Here is some how-to concerning how I did it. Doesn't make it right... just how I did it lol... hope this helps someone.
FYI, if you don't have the alumium carbide burr, (or the router d-moss used) I wouldn't try this. There is a lot of material to remove.
On the headpipe, I think it would be hard to do with out a long shaft burr like the one in the picture below. Just my $.02.

Tools you will need: 5D751979-7442-4E85-83EB-595AB4BE97F2-1877-000001F3CF229020.jpgB64D888F-067D-42C9-9762-F51024C3636D-1877-000001F3DBB0C67B.jpg

I basically 'gasket matched' the two openings.

Before:6BEE6B9A-5D9F-4EE0-A0FF-51CE87E5ADA6-1877-000001F367787FF6.jpgB14C55C9-02E1-4079-A491-AB84C7BBDE90-1877-000001F35F88B13F-1.jpg


I painted the flange black, then layed the gasket over. This revealed how much to remove and where. Intresting that its off center.
4017208D-F1B3-4884-951C-5F9CB552C6FC-1877-000001F36F997ACD.jpg

I used a screw to score the paint, so I had some guidelines to grind into.
5F6B9ED6-3234-427B-ABDE-AF31944DFBE9-1877-000001F38B33BB70.jpg

Grind grind grind...
I tried to carry the expansion down into the head pipe as far as I could. Check your measurements at the orifice, make sure its round and use your best judgement going down into the head pipe on consistency.
5EFCE7F4-CA46-4A66-9665-43418FF4BC62-1877-000001F3C82E7D15.jpg

Then I used the barrel sanders to smooth the rough finish. This isn't completely necessary, i've seen a lot of professional port work that was left with a 'burr' finish.
I used 50grit barrel, then 120, then a 240 flap style sander. Also, you may find spots that need to be touched up with your grinding burr, vs forcing major adjustments with the sanding barrel.

Finished product. The openings wern't 100% perfectly round, but I was within half a millimeter on both sides. I went about a half a mill farther than the gasket to get to 48mm, so i'll have to trim the head pipe gasket also.
91F15417-015D-462E-B6D7-71A92C64EC3E-1877-000001F3E6471910.jpg13286738-0DC8-455A-A1D1-CDD88BD09A3C-1877-000001F3F86DABC6.jpg

To give you an idea of how much material I removed.
5950A126-DFD1-4C59-BEE2-6FE08BEF1D12-1877-000001F40E3AE426.jpg

I did the same routine to the manifold, and also gasket matched where the mani attaches to the engine.
The headpipe is much more difficult because of the curve inside of it.

Hope this was helpful, if anyone has any feedback, please share. I defintely don't want to lead people to do the wrong thing.
 
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i know this is a old thread but
i ran across a sweet resleeved x cylinder w 760 sleeves and a badass port job and already has a b manifold on it
dug this thread up to see what the man outlet should be
mine is at 42 looks like i got some grinding to do
thought it was gonna be a quick swap
 
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