Ok thinking the early case build of the 88ci from ‘99 to ‘02 we’re built more robust using timken bearings on the crank etc and the cylinder jugs & heads from a 103ci will bolt right up to the 88ci to make a better flowing cheaper alternative 95ci upgrade with new pistons. Since the rods will be shorter in the 88ci effectively the engine should give quicker revs and get up to speed quicker provided optimum cams are used for max torque/horse power and new pistons are used to get correct compression ratio. Gears would replaces chains on crank and cams.


Or would it be better to have the low end done on a newer 103ci to replace crank bearings with timken and weld the crank and balance it so gear drive sprockets can be used on the cams and crank to cam? Not quite familiar with what all is involved in this process and of all the pros and cons in this scenario.


Thinking along the line of optimizing the engine for street performance while maintaining reliability.


I have not even began the hunt for parts to know what is even available. I like the idea of the 103ci for fuel injection “ ease of tuning and starting “ vs carbureted that can get all mucked up if left to sit for periods of time like over winter or unforeseen issues that puts the bike on the back burner for extended periods of time.


I know carb vs FI is a whole other toppic and can of worms as well as is sensors required for FI etc.

What are your thoughts?

 

I think id be pricing out an s&s drop in engine to see how far apart theyd be.

 

i'd agree with you

likely get a better performance engine than a 103 for teh same price

 

Stage II (95") factory kit is the biggest bang for the least buck. 20% more power (both HP and TQ) for about $1,000 in parts.
Everything above that is incremental and therefor more expensive.

You will certainly 'feel' the power gain from 68 to 85 hp, and torque around 95 ft lbs. What are you looking to gain?

If I'd go beyond that I would leave the bottom end as it and go with one of the available 98" kits from one of the sponsors in the Forum.

(I recently bought my '02 Dyna specifically for the simplicity of design and that stout bottom end. Couldn't be happier.)

 

Well I am in the process of researching and learning about different models and years and what engines came in each generation of twin cam engines.

So so far my understanding is the 88ci chain tensioner is the Achilles heel in this engine, easily repaired with a hydraulic chain tensioner or gear drive.

88ci ’99 to ‘02 the bottom end was stout with timken main bearings.

88ci ‘03 to ‘06 the main bearings were changed out so unless the run out is good on the crank then gear drive is not an option and even if it is good when the new cams and gear drive is installed then it could cause potential problems later on down the road should the flywheel shift and or mains wear out.

96ci ’07 to ‘10 the crank was lengthened to give more power as well as the chain tensioner went to hydraulic and the permanent addition of the Delphi electronic fuel injection which is praised for tunability and easy starting but then there is the weaker bottom end issue.

The biggest issue I can see with dropping in an S&S engine is California regulations and begging for attention to have Johnny law scrutinize my bike if and when I get pulled over and then there is the miss matched serial numbers and dealing with insurance. I’m new to all this so I have to look at everything to get a clear view of my best options and finances will lay a big part as well.

 

I used to get pulled over a ton in my teens and 20s and ive never in my life once seen or heard of a cop getting into checking engine serial numbers or even vins on a vehicle that wasnt stolen or already an issue in some other way.

 

S&s 111

 

Obviously you havn't been checked in California. Seems like every time I turned around they were checking ALL numbers on my Special Construction.


Edit: California includes engine #'s on the registration so easy for LEO to check.

 

no i havent. i couldnt be paid into going there.

 

As long as you get the certificate of origin for the engine all you need to do is go to DMV and get registration changed to reflect the engine change.