S&S 4" big bore cylinder and piston kit boosts Twin Cam 88 Harley-Davidson big twin engines to 100" displacement. This kit does not require any machining, rebalancing or engine removal, and includes just about everything you'll need to complete the installation. These are biggest cylinder bore that can be installed in a stock crankcase without machining!
Product Note:
| Specification | Details |
|---|---|
| Bore | 4 in. |
| Color | Varies (make selection above) |
| Compression Ratio | 10.5:1 |
| Country of Origin | USA |
| Displacement | 100 CI |
| Engine Type | Twin Cam 88 |
| Finish | Powder Coated |
| Material | Aluminum |
| Stroke | 4 in. |
Fitment is guaranteed or your money back plus free return shipping.
Don’t waste time installing a product that doesn't fit. We worked hard ensuring that this product is an exact fit on the vehicles listed below.
Be the first to review this product. How many stars would you give this product?
By Dakota T.
I'm in the middle of a build and have the option to run a nitro use kit and was wondering if the pistons the kit supply's are forged or not
Yes, these 100" big bore kits from S&S come with forged pistons.
By Marc S.
I'm looking to do the 100 inch kit but I have 509 cams in my tc 88. Should I change to the 585 or keep my 509 cams ?
No, there's no requirement to change cams just because you're installing this Harley-Davidson big bore kit. That cam will be more than up to the task of helping your bike achieve good power output!
By Anon.
Yes - absolutely. When it comes to S&S engine parts, they work really well together since they're all developed and tested by the same people at the same company. We have, literally, thousands upon thousands of very happy S&S customers at PartsGiant.com!
By Anon.
Yes, the cylinders are already matched to the pistons included in this kit.
By Macho
Yes, the 585 cams would be a great match for the 100" Big Bore Kit on that 2003 FLHR Roadking.
By SLIM
S&S doesn't state that it needs to be replaced or upgraded but wouldn't be a bad idea when doing any kind of high performance engine modifications.
By Anon.
S&S does not state that you would need to change the injectors or throttle body for installation of this kit.
By Jamey
It is an involved project for the average Joe to take on, especially with the amount of money these kits cost. We suggest having a trained professional take care of the installation of a kit like this.
By efrain
It is not necessary to upgrade either of those parts. If you want to get the most out of this kit, I would suggest going with a set of cams as well.
By pcarrai
Sidewinder big bore kits come with ductile cast iron liners fitted in cast aluminum jugs.
By Dame
Absolutely - with this kit, you can use any cylinder head configuration that would otherwise work with the stock cylinders. This allows you plenty of flexibility for your big bore build.
Have a question? Please ask our experts and customers who own this product.
