V12 XJ6 Conversion Build

Very cool info! so it’s basically saying you can use Speed Density for normal driving and putting around town and then it switches to Alpha-N when you go above 50% load?

old pic from Jaguar around 1968/70!
long runners, with injectors !DSCN8847 .!
injectors up before throttle plate !
engine made 500 hp , but at 8000revs, torqueless below 4500revs!
ron

Thats right, as vacuum dissapears quite quick when you open the ITB depending on engine speed and load.
Have never used it myself but what I can read from other users its working really well.

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Good to know i’ll look into it!

tobmag, you are correct , i drove a Nissan GTR , 1993, and when touching the throttle it seemed it was wide open , or dropping off like you lifted your foot!
very diffecult to drive in traffic , jumping ahead or hittin the brakes!

. .
but car was VERY fast
ron

About to buy some piston rings and I wanted some opinions. I see that there is a wild variance of price from the usual distributors. What I wanted to know is I found a set on Welshet that are $145 and have the same part number as the ones on SNG and they want over 300 dollars for them. They seem to be made by Hepolite which I have gathered is a reputable brand. should I pull the trigger on the ones from Welshet? I have not dealt with welshet before are they reputable?

https://www.welshent.com/Jaguar-53L-V12-Piston-Ring-Set-Standard-P11537.aspx

Ok thanks for the info. They seem to have better prices on a lot of stuff so i’ll order through them probably.

William,
I have this new ring set from Deves, for $75 plus post.
I’ll never use them,
Rob

Email me here: williamoeseburg999@gmail.com I want them.

Any update on your ITB project?

That packaging is a good idea. SWMBO’s first car was a Toyota Corona with engine problems. When I got it apart, I discovered that a previous mech had installed a wavy spring that was supposed to go behind the #2 ring behind the #3 oil ring instead, and this had obstructed the oil drain holes in the piston.

Unfortunately no. I was distracted by the XJ6 over winter break and ended up putting Johns Quarterbreed kit in. I have since started my spring semester in college and I am taking way to many classes to have enough free time. So unfortunately it’ll have to wait until I have some time free to really focus on it.

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Didn’t want to make a new thread for this but did anyone know that Jaguar still offers tappet blocks with caps new for only 80-ish dollars? I might one up as on of my tappet block bearing surface has pitting in it. correction only the right-hand side is available.
https://www.sngbarratt.com/us/#!/English/parts/385fa8dc-0fc4-464c-9cb6-05d62076eaa1

https://parts.jaguarlandroverclassic.com/jlm11897-tappet-block.html?code=C06122063830

Admittedly, that’s a very un-Jaguar-like price.

If the putting isn’t too bad, I doubt it’d effect the operation of the block.

Yea earlier in this thread we determined it would be fine but for 80 bucks I figure why not get a new one. still might use the old one though.

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Ok a little update. I have had some time recently to work on getting the heads off and I have made some progress. I have the passenger side head popped up about 1 inch, and just as I anticipated it’s getting stuck due to a couple studs having a lot of rust and crud built up on them and jamming the “bore” the stud sits in. I made a lighter weight tool and decided the remove as many studs as I could before trying to pull the head off. I like this method as I am already going to replacing all of the 7/16" studs and the tool seems to hold up fine… apart from me literally ripping the threads off of grade 8 threaded rod. I managed to get 7 of the 10 I attempted to pull out. 3 snapped on me though. I am contemplating just getting a hand saw of some form in there and cutting off the offending studs on this head. But for now I am going to move on to the other head. I’ll post more updates when I can.

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Looks like the head is racked, be careful!

Forgive me but what does racked mean in this context?

It looks like it is not coming off the block square to the studs.