If anyone is interested Norman Lutz has 95mm liners available, These are the same as what he put in my 6.7L

https://www.ebay.com.au/itm/JAGUAR-V...frcectupt=true

 

i wish this stuff was available 26yrs ago, when i had plenty of money,, retired on fixed income!
changes how we live life ,, Oh well !
ron

 

Been investigating my options for a jag v12 build and seams you Warren know your stuff so I only registered here for the sole purpose of draining you for knowledge and information.
is there any way we could do this?

 

I’ve still got a few V12 engines sitting around. Pretty simple to knock the sleeves out( I made myself an aluminum hockey puck to do just that) chuck them in a lathe and bore them out doesn’t take all that long.

 

MG i.m almost 86 yrs old , sold the machine shop and now retired!

and i dont need to touch my V12 , runs great, plenty of power(for me).
never thought id say ," its all i can handle" .
ron

 

Yep no problem, all of my info has come from Norman Lutz.

You can not bore the stock liners to 95mm it makes them too thin and prone to cracking. 95mm liners are available and the block needs to be bored to accommodate the larger liners. If using a 6.0L crank chev 305 pistons can be used. If using a 5.3L crank you will need custom pistons, or offset grind the crank and use chev rods.

I'm happy to answer questions and if I don't know I will find out.

 

I wanted the 95mm liners to avoid machining simply by buying new 6 litre liners, but now seams like a vaste since I need machine the block instead.
seen that you wrote about wrx pistons and Holden 202.
trying to investigate what combination is better for boost.

 

Holden 202 pistons have been used before but these are hard to get hold of now. WRX pistons after a lot of research will not work the compression height is wrong.

6.0L liners are the same as 5.3L liners except they are slightly shorter at the bottom where they slip into the block. To use 95mm liners you cannot avoid machining the block.

If you are going to turbo a HE why not just leave it 5.3L and machine the piston crown to lower CR. A turbo 5.3L is a sweeter engine than a turbo 6.7L and the 5.3L will still make 500hp

 

how much boost? Which engine HE or PreHE ? With the pre HE I kludged a set up using two junkyard turbo’s from Saab’s. Using 6 psi It got me to within a whisker of 500 hp on pump gas. The one “trick” to getting the stock pistons to live with boost is open up the end gap of the piston rings.
Jaguar pistons are pretty decent. You might get them to live with up to 10 psi. ( assuming you can richen the fuel mixture under boost properly ) *
* two ways to do that. Early 75-77 EFI is just the Bosch system tripled. Dial in 35 Psi instead of the stock 31 psi and trigger the cold start injectors to come on at 2 PSI. With an trigger hooked up to measure boost. The system starts and runs rich except at near 6 pounds of boost. To avoid fouling the plugs use Champion gold palladium plugs.

Much easier would be to buy a mega boost system to replace the Lucas system. Work sensor by sensor until everything is correct. The easy way is to swap the Bosch/Lucas sensors for GM sensors out of the 6 cylinder Trail Blazer. Even the injectors would be sized right.
Today I’d just replace the injectors to use E85. Using a pair of EBay T2 turbo’s & everything else stone
stock you’d be at 550 hp. Replace the camshafts with something more suitable for racing and up to another 100 horsepower is possible.

The turbo’s have to go out of the engine compartment and behind the front tires inside the fenders. Plumbing is simple. With the ethanol in E85 no need to run intercoolers.

 

MG thats nice , be simple enough(i think).

 

A 600hp 5.3L in a race XJS twin T03, custom forged pistons, These pics are of the original 6.7L preHE (over 600hp) which spun a bearing. Bruce replaced the engine with a 5.3L HE and still made 600hp

 

boost is the easy button for Pre HE engines. If like me you shop at junkyards, it’s even affordable.
The one issue is getting enough fuel into the engine. Unlike common engines Like Honda, Chevy, Toyota, where it’s easy to “plug and Play”. There is a lot of work to do. I kludged mine but there was a lot left on the table. Someone with the skills could really make the V12 sing.

 

I’m sorry but that couldn’t be a worse idea. The HE piston is flat topped. To drop a 11.5 compression engine down to 7.8 you’d need to remove enough aluminum to strike air.

 

Got a HE, but if a pre HE is available I have few doubts about a swap if the price is right.
I think the HE would give better fuel consumption if suitable pistons could be sourced.
I got a emerald ECU I plan to use and run the injectors as grouped since I only got 6 injector drivers on it.
the ecu has a analog input that can be set to change between 3 different maps so my idea is to keep one for economy, one for trackdays and one for highway. My power goal will be limited by what internals I can source without having to sell a kidney or prostitute myself.

 

You don’t need or want a Pre HE. Just the pistons and heads. The heads massively outflow the HE heads. The HE heads were done to meet upcoming California smog emissions. And increase part throttle fuel economy.
The Pistons could be as high as 9.0 depending on if you will be running E85. That’s the magic. The added power and much greater cooling of alcohol.
You could get by with less boost and use windshield washer fluid ( I know it sounds crazy, but it works ) as a supplement if you aren’t going to actually race the car. Just occasional full throttle blasts

You are aware most Jaguar ECU’s are analog while most aftermarket ECU’s are digital and use digital inputs. Properly developing “maps” is very complex and if you are adding boost massively more so. Plus the map for Gasoline would be different than the map for E85. It’s hard to get gas much over 93 octane while E85 yields 100+ octane. The added octane and different flame front will require either an additional sensor or complete dedication to one fuel over the other.
There are some digital ECU’s for Jaguars but they are rare. I’m not sure any came to America.

 

an digital ecu don't rely on digital inputs alone. But all analog inputs are converted to binary values in a 8 or 16bit resolution.
it's getting harder to find 98octane pump gas here, but 95 is standard. I have so far never seen 92 anywhere here.
E85 was a thing some years ago, but I not seen in in pump for years now.
Emerald ECU supports 3 different maps that can be selected by pull-up resistors on an analog input. Been running it on a old Opel
​​

 

I do not where you are in the world but why don't you talk to Norman Lutz, he has built a lot of race V12 engines and knows how to get these V12 to make power.

 

To drop CR to 8.5 you need to take 0.050" off the top. IIRC when I measured my pistons the crown was about 0.200"

 

please look at a HE piston and then the 7.8-1 piston and tell me a .050 haircut will drop the compression from 11.5-1 to 8.5

 

J