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so has anyone actually made 500bhp from a v12 pre.he

XJS ( X27 ) 1975 - 1996 3.6 4.0 5.3 6.0

so has anyone actually made 500bhp from a v12 pre.he

 
  #901  
Old 03-04-2019, 09:06 AM
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Hanging with that Porsche is kinda cool but that's a lotta work to get to that point considering the Porsche has 1/2 the turbo's and 1/2 the cylinders.
 

Last edited by icsamerica; 03-04-2019 at 09:13 AM.
  #902  
Old 03-04-2019, 09:55 AM
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sure aint no beauty queen , just ugly looking!
 
  #903  
Old 03-04-2019, 03:59 PM
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Originally Posted by warrjon View Post
This is a pre-HE head with hand shaped chambers and Chev LS1 valves.



The only issue with this is in Australia adding a turbo to the V12 requires engineering certification. My brother went through this process with his Shelby GT500 Mustang and it cost him over $20,000 to get the car engineered, they made him de-tune it and provide dyno sheets from an approved facility or it would not be registered. 700hp was too much.

There are a couple of twin turbo XJS V12 road cars in Australia but these were built in the 1980's before fun police put all the rules and regulations in place.
.

,, DARN i thought OZ was a FREE country??

in TEXAS we can do almost anything to our cars!
after 25yrs NO inspection required special plate for rear only, no front plate, so Vanity plate, like



 
  #904  
Old 03-04-2019, 07:28 PM
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Ron that maybe why the road death rate in Texas per capita is more than double Australia.

Originally Posted by ronbros View Post
.

,, DARN i thought OZ was a FREE country??

in TEXAS we can do almost anything to our cars!
after 25yrs NO inspection required special plate for rear only, no front plate, so Vanity plate, like
 
  #905  
Old 03-04-2019, 07:52 PM
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[QUOTE=LongJohn;2035400]
Ron that maybe why the road death rate in Texas per capita is more than double Australia.

NO its more to the demographics, of the area! its expanding at an alarming rate!

and comon grow up, there are more people where they come from!

ron
 
  #906  
Old 03-05-2019, 12:27 AM
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Ron, I see people from all demographics driving cars, pickup trucks and towing trailers all the time in Texas that are far from roadworthy. Some of it fun... an idiot in a pickup with tiny wheels overtook me on a bend and slid off the road. And please hold off on the insults.

[QUOTE=ronbros;2035413]
Originally Posted by LongJohn View Post
Ron that maybe why the road death rate in Texas per capita is more than double Australia.

NO its more to the demographics, of the area! its expanding at an alarming rate!

and comon grow up, there are more people where they come from!

ron

 

Last edited by LongJohn; 03-05-2019 at 07:47 AM.
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  #907  
Old 03-05-2019, 06:37 PM
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[QUOTE=LongJohn;2035497]
Ron, I see people from all demographics driving cars, pickup trucks and towing trailers all the time in Texas that are far from roadworthy. Some of it fun... an idiot in a pickup with tiny wheels overtook me on a bend and slid off the road. And please hold off on the insults.

[QUOTE=ronbros;2035413].

fair enough will do!!
 
  #908  
Old 03-07-2019, 03:49 AM
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Rob Beere HE heads with matching pistons.
 
  #909  
Old 03-07-2019, 03:53 AM
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  #910  
Old 03-07-2019, 05:35 AM
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Longjohn
Please explain to us a bit more detail about what has been done and what power it is expected to develop. That inlet valve looks huge. Lovely looking work by RB, that is for sure.
Thanks in advance
Greg
 
  #911  
Old 03-07-2019, 11:53 AM
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Originally Posted by LongJohn View Post
the sparkplug is still in the wrong place, flame travel will be slow for the far end of chamber , that could lead to detonation!!
it looks like plenty of swirl& squish, but BMEP would suffer!
 
  #912  
Old 03-07-2019, 11:56 AM
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and the cost of such is out of reach for most people!
i wonder abut valve size , maybe offset guides,donno!
but lets see it on the dyno!
ron
 
  #913  
Old 03-07-2019, 12:00 PM
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rob beere technician tuning!
 
  #914  
Old 03-07-2019, 02:08 PM
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Exhaust valve looks bigger too. I am surprised they have not removed the threads for the spark plug and smoothed the pointy bit between the intake and exhaust valves as these will get hot and cause detonation.

I know RB sells 1.71" intake valves that will fit in a stock seat. I looked at these but ended up going with stock size stainless intake valves.
 
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