113 build - Polish the HTTC Heads? Mikuni 51?

Hey Mike; I am getting set to do a 113 build on my '06 carburated Street Glide. I do a lot of two up, loaded up touring with my wife but also like to get out and beat up pavement with the guys if you know what I mean. My goal is lots of power Torque and HP. I'm thinking 120+ Hp with Torque numbers to match. I would like the power most accessible in the 2500 4000 range as that is where I'm riding most of the time ( more like 2500 - 3500 with the old lady on board). I thought about a 6 speed but I'm pretty happy with the stock 5. I'm thinking to change up the tranny pulley so that I drop 200 - 240 at around 65/70 mph. My shop is suggesting the usual stuff and I am suggesting a couple of variations.

The usual stuff includes:
CNC HTCC HEADS
TC88 STROKER FLYWHEEL
SE PRO "BIGGER-BORE" 113
SE PRO TC HTCC STROK
QUICK INSTALL PUSHROD
SUPER BORE 51MM CV CAR
SE 255 CAM KIT
SE IGNITION RACE TUNING KIT
I'm still deciding on exhaust but am leaning to 2 in to 1. looked at the V& H Ovals and heard they are good choice for a nice even torque line.

I have a few of questions that I would highly appreciate your opinion on:

1. Do you think that that the CNC HTCC heads would benefit from a bit of polishing? I have heard a couple of folks become critical of these heads but on balance most folks seem ok with them. Thoughts?

2. I was at the bike show and saw first hand difference between the chain driven and gear driven cams. If I went gear driven what should I be looking at to get in the range that I like most power?

3. Is there a Mikuni 51mm carb and would that be an improvement over the Super Bore 51?

4. Are the Quick Install Pushrods the right model for the HTCC head?

5. I want a nice curvature on the touque line no early drop offs and that kinds of stuff - just steady pull from the get go - I was thinling about the Vance and Hines Pro Pipe but also want to keep the neighbors happy. suggestions here.

6. Do you think I should consider any clutch work with the bigger power?

7. Do you think this build will hit the numbers that I am looking for?

8. Do you think this build will be a strong build giving lots of reliable miles?

Thanks a lot for this Mike. I just found your site and gotta say it's the best information I have seen. Keep up the good work Boss!!

Another Mike

[Mike]

Apologies for late reply, playing catch up. Only thing I see in the build are the 255 cams. I do not know if people have ran the numbers on these or if they are choosing them because they are new. With the correct pistons to use with those heads you'll be at 10.5 compression (not listed on your reply, but I assume that is what will be used). It is VERY likely to have severe detonation, heat and starting problems (even with compression releases). Cylinder pressures will be way too high causing difficult, if not impossible, tuning issues. Better choice would be the 258's or similar. the 251's or 257 could be other choices, but tuning will be critical and starting may still be an issue.
To your questions;
1. Do not polish the intake ports. This will cause fuel seperation and reduce power, the CNC finish is nearly perfect. You can polish the exh. port and combustion chamber to minimize carbon build-up, but this is only temporary, over time build-up will occur. Better to have the chamber, exh port and exh valve ceramic coated to keep heat in the port and pipe and out of the head casting, guide and valve stem.
2. The T-man 590 or 650 cams will work. Other choices would be the TW9f, S&S 585 or 625 and Andrews 67. All available in gear drive. This is a big motor with big ports and will take deep breaths, so it can stand (and want) more duration and timing vs. smaller motors.
3. The Mikuni 48 would be my choice but the 51 CV is more user friendly. Because of the smooth bore design, Mikuni's flow more air size for size vs. a butterfly carb and so can be smaller. Zippers, Rivera and T-man all have excellent Mikuni kits. The 48 is the largest Mikuni currently available and some shops are modifying them to flow more air for larger motors.
4. The quick installs will be fine and allow for more cam choice options (base circle differences will not matter).
5. Check out our dyno library exhaust files on this site for examples of how many types of exhaust have worked o builds or tunes we've done. The VH Pro will have a torque dip around 2.7k but not as bad with the larger motor size of the 113 vs. a 95. The VH Ovals on your stock head pipe will produce the best power from 2-4k but will fall off above that, more so with a bigger motor. We do a "y" pipe mod to the stock head pipes that helps with large motors. Another good choice may be the DD Fatcat 2-1 but it'll be a bit louder than the VH's. Your exh choice will be the single biggest influence on the shape of the torque curve (more than the cam choice).
6. Yes, you'll need to upgrade your clutch. We like the AIM/TPP lockup. You can get more info on this on their web site www.aim-tamachi.com.
7. You will not hit your projected numbers with the 255's. With a freeflowing exh (bad for 2-3 area) and more appropriate cams these numbers are very realistic (based on 5th gear runs corrected to STD). An exh that helps the 2-4k area may dip down to 115 hp peak but you may also see 120-125 torque.
8. This should be a very reliable build. More so with an exh that focus' on the 2-4k area because the motor will not have to rev'd as much to make power for passing, hills or just plain accelerating.
Thanks, Mike

This is great Mike. Exactly the kind of information that I was looking for. I have to say after some time digging around and comparing build data, cost etc. I decided that it makes more sense to go with the Jims 120. Much as I am intrigued by the idea of a custom 113 build the Jims 120 seems the better choice for me. I am going to take your suggestion on the V&H Ovals - seems that they will work best in the range I ride most of the time. I am interested in the "Y" pipe mod. What is involved here? I assume that the AIM/TPP lockup will work just as well with the Jims 120?

BTW - The guys at JIMS told me that changing the tranny pulley will steal a whole mess of power so that's not on.

Thanks Boss - I gotta say you sure no how to cut through the stuff.

One last question here Mike - I am buying an already crated JIM 120 - would it benefit from Dyno tuning once installed?

Thanks in advanced for all your help.

another Mike

[Mike]

Thank you for the kind words. I always recommend a dyno tune to gete the best out of a new motor or just to know that it is at it's best. The 120 is a good choice and we typ. recommend it when we get into talks about building 113's or others. The pulley change will rob a little power but not a ton (about 4). The "Y" pipe mod removes a restriction where the rear pipe fits into the front at the "Y". We can do it for $50.00 if sent to use or you can do it with a hand die grinder.
Mike