BLACK SUNSHINE the 300 HP FJ

[fjmods]

I am almost certain he told me he had not made any alteration to the standard FJ compression ratio. At 10psi boost I'd say it was entitled to let go !

Actually thinking about it, with 1219cc pistons his compression ratio could have been even greater than standard. He could have been running an effective CR of around 13:1  !

[ddlewis]

I remember when Jarosz was building this bike. As I recall this was on the old netpath list probably 10 years ago now.  Surprised so many remember the bike by name, it's become sort of an FJ legend. 

[Bob]

...
But the worst issue Jon had with the bike was when it went BOOM!   
sometimes too much is really too much!
...

Jon had the bottom end of that engine sitting in his garage for while. 
I took it off his hands a couple of years ago and transplanted the APC clutch kit into my "Shadow of Black Sunshine".

[Bob]

I have a copy of Jon's original web site, including the pictures (it reminds me how shiny the bike could be).  If there is a way to host them somewhere I'm happy to zip up the files and send them.

In the files section you can zip them together and attach them to a post.

The web site files have been uploaded to the files sections as "Black Sunshine web site files".

[Marsh White]

Page 1:
http://www.fjowners.com/blacksunshine/Black_Sunshine1.html

Page 2:
http://www.fjowners.com/blacksunshine/Black_Sunshine2.html

The in-line links do not work.  I'll fix them when I have a bit more time.

[andyb]

Lovely work.

[fjmods]

Reading the article Jon confirms he was running 10.25:1 CR. with 10psi boost and NOS. Without other work IMHO it was always going to end in tears. 

[andyb]

A thick headgasket and/or base gasket would comfortably solve that.

[carsick]

Any idea what kind of power this bike made?
Thanks
Mark H.

Mark, please refer to the title of the post topic.

[fjmods]

A thick headgasket and/or base gasket would comfortably solve that.

Certainly wouldn't have hurt Andy. I think APE used to make a set of cylinder studs that would have held the whole lot together a little more 'snuggly' too !

[Coronet]

Doug -- sure missed that one, thanks.
Cyl studs would of helped but compression was still way to high. Tried running 10.75:1 in my car motor with ARP cyl. studs, solid copper head gaskets,  and o-ringed heads. Could not get head gaskets to hold for long and actually ruined one cyl. block by stressing the crank main journals so much that the main caps would just fall off when you removed the stud nuts - no regester left. Suspect this was from some undetected detonation - caused by the high compression - and yes I was pulling the timing way back under boost and running race gas. Detonation is the killer of boosted motors.
Finally had JE build me a set of custom blower pistons with dished heads and thicker ring lands, compression now was 7.55:1. Actuall pushed the boost up to 18 psi with this setup. Funny thing was that after about 13-14 lbs boost I did not see much increase in power. I suspect this was because the roots type blower was very good at heating the intake charge a great deal at this boost setting (no inner-cooler) and causing detonation issues. Not to mention that super hot air is a lot less dense (less oxygen) than cool air.
Then there is the "blower sneez" blower backfire. Been their done that, bent rods, bent blower rotors, and thats with a pop off valve on the blower manifold.
All in all still would have loved to see Blach Sunshine actuall run down the street with the blower on it. Cool as Hell.
Mark H.

PS -  not sure how I got off on thst tirade.

[rktmanfj]

All in all still would have loved to see Blach Sunshine actuall run down the street with the blower on it. Cool as Hell.
Mark H.

There was at least one video of her running, but I lost it a long time ago.

Randy T
Indy

[fjmods]

Doug -- sure missed that one, thanks.
Cyl studs would of helped but compression was still way to high. Tried running 10.75:1 in my car motor with ARP cyl. studs, solid copper head gaskets,  and o-ringed heads. Could not get head gaskets to hold for long and actually ruined one cyl. block by stressing the crank main journals so much that the main caps would just fall off when you removed the stud nuts - no regester left. Suspect this was from some undetected detonation - caused by the high compression - and yes I was pulling the timing way back under boost and running race gas. Detonation is the killer of boosted motors.
Finally had JE build me a set of custom blower pistons with dished heads and thicker ring lands, compression now was 7.55:1. Actuall pushed the boost up to 18 psi with this setup. Funny thing was that after about 13-14 lbs boost I did not see much increase in power. I suspect this was because the roots type blower was very good at heating the intake charge a great deal at this boost setting (no inner-cooler) and causing detonation issues. Not to mention that super hot air is a lot less dense (less oxygen) than cool air.
Then there is the "blower sneez" blower backfire. Been their done that, bent rods, bent blower rotors, and thats with a pop off valve on the blower manifold.
All in all still would have loved to see Blach Sunshine actuall run down the street with the blower on it. Cool as Hell.
Mark H.

PS -  not sure how I got off on thst tirade.

I suppose in fairness to Jon he was sorta treading on relatively rarely trodden ground. I run a blown SB Chevy myself. It's a well trodden path really, all the bits are off the shelf. Ya can't say that with an FJ !! 

Good hit Jon, you secured your place in FJ folklore 

[Coronet]

  No disrespect to Jon at all!  Infact I give him all the Kudos in the world for even traveling down that road. Its not easy or cheap to build a bike like that. Sure can't walk in to your local speed shop and order the parts needed.

[Arnie]

All in all still would have loved to see Blach Sunshine actuall run down the street with the blower on it. Cool as Hell.
Mark H.

There was at least one video of her running, but I lost it a long time ago.

Randy T
Indy

I have the clip of it running, but the bike was static.  I can post it up to the gallery if anyone wants to see/hear it.

Arnie