I use the stock diff with an lsd unit inside, swapping out a diff can be some work, but it is also a good opportunity to replace all bushings. I have done it myself without a car lift, its not easy this way but doable.


The engine is a standard 4.2 block, I haven't changed anything. It has already survived 60Kmiles with a power output greater than 450 rwhp, and now with about 10Kmiles above 500 rwhp.

I use only the best oil for it (imho M1 0w40), never use the power when the engine oil is not up to temp, and of course maintain it well. Not sure how much that contributes, but I think at least something, most will be coming form the strong design of the block itself of course.

 

I wish Ihad the money for a twin screw........Give me time Ill be there.

 

Thanks!! Wow! That's a testament to the Jag's bottom end.....and your bravery!!

 

Group buy!?!?!

 

Humm, ...???

 

Uh... Have you never heard of that term?

umm... here:

Group buying - Wikipedia, the free encyclopedia

 

I would consider a grooooooop buy.

 

I am open for it, but to make a difference I would have to buy at least 5 sets of parts from my suppliers. I don't mind to buy 1 set extra to have a set ready to go, so that would leave 4. I guess up to 10% discount might be possible, but need to check it as 5 isn't a significant number for my suppliers...

 

Has anybody ported the stock blower? I was told that this is a very viable alternative and also adding pulleys would be very good.
http://horsepowercalculators.net/tun...-modifications

http://www.stiegemeier.com/porting.html

Porting for 395?

 

For small power upgrades a pulley would do fine and is relatively cheap, but the Eaton is already at its maximum efficiency, so spinning it faster will make it less efficient (the power doesn't grow linear with the speed of the unit).

The next enemy you need to battle is the extra heat the (h)eaton generations, as that will lower the output again.
Here is a rough calculation I once made, that should give you some idea of what is happening:
https://www.jaguarforums.com/forum/x...31/#post189725

Porting will make the unit louder, that is at least 1 thing that is confirmed, but that it adds power on our cars, is something I would have to see creditable dynos of, after 10 years that this is available I haven’t seen these yet.

You will have to spend some good money to even get 50 hp more out of the unit, and that includes all sorts of other upgrades, from exhaust/catalyst/ecu tune extra cooling etc.

So you need to determine what it is you are looking for, the twin-screw kit is in a whole other league.

 

I would be interested if you have ever made plots like these comparing the TS to the (h)eaton. My feeling would be that volumetric efficiency is a steeper slope and delta T is lower and probably flatter across the RPM range of interest for a given PSI.

 

I don't have any data for the KB2.6LH version (or others), but take the extra horses already meant something ;-).

The calculation made was a try to help others understand what happens if you speed up the eaton. When I still had the eaton with a larger lower pulley that gave about 16 psi, a dyno showed only 315 rwhp, but was probably heat soaked. Of course I did feel the power kick in earlier but also how it diminished with heat buildup. That major disappointment triggered me to look for something that does work, so started to test twin-screw setups.

 

Point taken.

Are you still using the stock inter-cooler or something larger? If you can make that much power with the stock one, it would be a real testament to how much lower the charge temp is.

I live in the desert where it can easily be an ambient temp of 110F. On a black road that's in the sun, it is probably more like 130. Combine that with the fact that 91 is the highest octane commonly available around here and thermodynamic efficiency gets to be pretty important.

 

With the KB 2.6LH there is just no comparisson to the eaton, so you will always have a vast headstart in combating heat. What are you actually looking for?

 

I'll email you directly so my questions don't take up so much of the public space.

 

Well if we can get a few other people, consider me in.