the two suppliers I see recommended the most are NRHS and Hammer.

Here's a list from Hammer, gives you an idea of what is required at each step up the horsepower scale

http://hammerperf.com/883conversions.shtml

 

If like like arm jerking power then do cams and ported heads. The results will blow your mind. Like everyone else said, What are you looking to do? And what is your budget? A lot of guys give out incorrect info on bikes with ported heads and cams. That they are radical or not reliable and what not. Depends how deep you get into them.

Like i said if you like speed and power, an upper 90s 100 hp sporty is not even close to being in the same league as lower 80s hp.

As far as a 1250 kit goes, Im not sure if revolution perf is still using the nikasil junk, if they are , thats just asking for a possible headache.

Hammer performance has 1250 kits. And they have the big fin style to match your cylinder heads.

 

The NRHS Connection


Many people ask use about our connection to NRHS. Let's clear this up.

The CNC billet parts, head porting, and other machine shop services sold by NRHS for several years were actually sourced from companies owned by "HAMMER Dan" Norlin and Aaron Wilson. NRHS essentially served as a retail outlet for these products and services, and there were a few other retail outlets as well.

Dan Norlin and Aaron Wilson then formed "HAMMER PERFORMANCE" to bring these parts and services direct to you. The product designs and head porting technology behind all of those NRHS results for so many years actually belongs to HAMMER PERFORMANCE, and we are the direct source.

As of Spring 2012, we terminated the relationship with NRHS. HAMMER PERFORMANCE is now the only place you can get the the technology and services that have set so many records under the NRHS name in both drag racing and at Bonneville for so many years. In fact, to this day NRHS continues to advertise using results that came from our products and services, as well as pictures of our work, even though our work is no longer available through them.

But that technology has not stood still, not by a long shot. Although they've been working together for a number of years, since forming HAMMER PERFORMANCE Dan and Aaron have ratcheted up the R&D, incorporating more technology and innovation into the designs and processes than ever before, to bring you the best products yet. We're proud to say that we're hitting new levels of performance that were not achievable just a few years ago. And we're not sitting still, we're always working on new ideas and products to to bring you higher levels of performance with the reliability, longevity, and quality you demand.







This is from hammer performances website.

 

As per Madnss Hammer has been doing some amazing things, if you do a search they have some dyno sheets posted on the forum and while your at it check out Madnss videos, impressive

 

+1 on NRHS. customer service is top notch and the product is amazing. call them up. tell them your budget and they will guide you the right way.

 

Read post #13.....sorry but nhrs has not put out any proof of power from their in house head work.

 

Have you had the bike tuned? When did you have the work done?

 

headwork, cams, and exhaust matching has a lot to do where your power is in the rpm range. I would suggest you contact either Dan at nrhs or Dan at Hammer performance or both. You will not be disappointed talking to these guys even if you just get one of their 1250kits.

 

yes...that damn exhaust has a bunch to do with it.