Getting a sense that a headswap is not straightforward,
Head tuning is a black art to me, I kinda understand the basics, but the number of variables make my head hurt.
So -
Bang for buck lightning/ XB / >04 XL head?
I neither have the knowledge nor machinery, recommendations for who could do the work (familiar with buell)?
Stepping out of my comfort zone, so please forgive any dumb questions.
Thanks again

_________________
Today my pet mouse Elvis died ..................He was caught in a trap
There are two types of people in this world, those that can extrapolate

Here you go...

viewtopic.php?p=110849#p110849

And here...

viewtopic.php?p=154084#p154084

_________________
08 Specialized Langster

Nick, what did Grenade dyno at after fitting the XB heads? (I recall it was 80bhp with Lightning heads?).

_________________
Try doing this to yer fueller...........

95...

_________________
08 Specialized Langster

Impressive, for stock XB heads and SE497 cams. Bet you're well happy with that result. I'd say that is a pretty well optimised S1 for its spec. I'm not bothered about dynoing my similar-ish spec M2 but I'd be surprised it was over 90 rwbhp.

_________________
Try doing this to yer fueller...........

Very nice of you to say. Beef's 1250 was 105, Mojomick's is not far off mine with Thunderstorms. My Firebolt was 91 on the same dyno (corrected for atmospheric conditions).

The HP doesn't tell the whole story though, as with the Lightning heads the torque started to drop off at around 3500rpm (IIRC) but now it stays constant up to the rev limiter which is awesome for overtaking cos it just keeps going.

Regardless of optimisation (I run the same ignition unit as yours), I am sure you noticed a huge difference like I describe...

_________________
08 Specialized Langster

No, HP certainly isn't everything. That's why I still strongly recommend the OP to invest in full US gearing, probably then resulting in fewer 100mph thrashes down the motorway, a risky past time these days anyway, and more back roads miles. The flat torque curve is a testament to how well the motor is breathing through the better heads and the care taken in building. Given that the resulting 15bhp increase doesn't involve any exotic CNC porting, mega lift/duration cams or high tech piston designs and uses standard off the shelf parts that don't cost a bomb, it's a model build for a 96/98 Lightning motor really. If a budget was stretched, you could even use the standard CV carb on that build which I'm sure would equally support the 95bhp and save a few hundred quid.

_________________
Try doing this to yer fueller...........

Fully agree

_________________
08 Specialized Langster

I did some digging on the Sportster heads (as I did back along) and could not find any on eBay. To buy new they are around a grand for a pair...

My XB top end was £100 and came in a top box which I later sold for £60...

Those were the days...

_________________
08 Specialized Langster

WOW!!! This stuff is getting expensive. I remember buying brand new fully assembled Thunderstorm heads for ~$500 a pair, sold them on unused as the 04 XL heads came available. From memory the 04 XL heads were a bit cheaper than that but came bare (only guides fitted/reamed) so you had to buy the valves, springs etc separately. The XB9/12 valves, springs etc I remember buying for mere buttons. I used to buy all my stuff from Chicago HD who used to offer 20% off the HD book prices. I remember having about a 50% chance of having to pay VAT and duty at the time. With a £1 being worth anything up to $2.05, buying parts from CHD was silly money really.

_________________
Try doing this to yer fueller...........

As a matter of interest, Hammer Performance are offering brand new XB heads, CNC ported, bronze guides, valve seats cut/lapped, valves stem height, springs etc set up, chambers cc'd, heads decked flat, blah, blah.... For $1292 which still sounds pretty cheap even given a weak £ at the present. That's likely going to be a 20bhp bolt on job for a 96-98 Lightning motor?

_________________
Try doing this to yer fueller...........

Just been looking at something similar
http://www.nrhsperformance.com/partsoemheads.shtml

_________________
Today my pet mouse Elvis died ..................He was caught in a trap
There are two types of people in this world, those that can extrapolate

Interesting. Lots to consider. Fascinating how the prices have gone up in the past 12 or so years since I last bought this stuff. Wish I'd invested my pension money in Buell/Sportster parts.

_________________
Try doing this to yer fueller...........

Don't forget to budget for a front engine mount to fit these heads plus XB rocker covers and PCVs

_________________
08 Specialized Langster