i want to put new pistons, bearings, head gasket, cams and valvesprings in the engine. then mate up handmade turbo headers and downpipe mated with an Audi intercooler pushing to a custom stainless inlet manifold with new Bosch injectors. this should be a good combo. but why has no one seemingly built an efi 4.2? i think im the only guy with a custom fuel delivery! if anyine has any serious modifications to the 4.2 or a series 3 post it! i need ideas!

 

I've actually been doing some digging on installing a turbo on the 3.6 in my 89 but haven't found any real guidance either. So if you start doing this make sure to post up as you go along.

 

There are a few built 4.2s out there but all normally aspirated as far as I know. The XK six cylinder is a wonderful old engine but the design is over 50 years old. There just isn't much interest in it these days.


Keep an eye open on Ebay for a book call "Power tuning your XK" or something like that. It was written ages ago but I doubt anything new has developed since then to make it obsolete.


Or you can save a lotta time and money and just buy and XJR :-)

Cheers
DD

 

I suppose it could be done, but the costs to do it right would be enormous. And then you'd need to swap out the trans, the S3's BW is a weak unit to begin with, start increasing power (torque) and it'll go bang quite quickly.

Ditto with turbocharging an XJ40, you'd want a low-comp engine out of an early 88 with a "SAJHV15" VIN versus an "SAJHV16" and you'd still need to find a way to get an MLS head gasket for it, and at the very least have the trans rebuilt to take the torque. Personally I'd do a manual conversion

 

the driven man.
im welding up most of the modifications to start with im going to put the cams, modified and cc'd head,the turbo,manifolds and inlet manifold on and dial down the boost to a drawling 5 psi. then the internals and trans. im going for a t5 or a tremec along with a new radiator. which leads to an airdam and induction & hoodscoop fiberglass hood. im aiming for total compleation in five years im only spending 500 dollars on the origanal modifications the injectors could be the most expensive thing i buy. the trans i will buy used and wrecked and put new gear ratios into it. the glass will all be done at once front end, lower rear quarters and deck lid.
the car isnt worth anything and i dont care if i destroy the origanal because its so rotted i may replace the floor with an aluminum honeycomb sheet.

 

the car is sitting with the valve covers off and there are gouges near the... i forget what the caps that cover the valves that the cam hits is called (mind fart) however it is gouged up and there was the infamous sewing macine noise loose cams? btw the wear looked old and new as in its still happening and was happening when it was parked. here is the cam i want:

 

There is a tri-turbo and single turbo XK engine profiled in the books "Maximum Boost", and "How to Tune and Modify Engine Management Systems". The engine was in an E-type, and I believe it was built by Corky Bell, author of Max Boost. The second book I mentioned has an online preview available through Google books, you can search it out if this link doesn't work. The turbo XK engine section starts on page 211 of the online preview. They test the same engine with a tri setup, and a single turbo.

I used to own a copy of Maximum Boost, it had a lot of good info, and detailed how the tri-turbo exhaust manifolds were built out of "weld els", which I believe is another name for weldable thick wall cast steel pipe sections that come in straight or curved shapes. The manifolds turned out nice.

So, it has been done, but it is definitely not common. I have not found many examples of it. Nowadays with the popularity of DIY EFI like MegaSquirt, I wish some more people would get creative with these engines. If you feel comfortable doing a little tuning with a wide band O2 sensor, a dyno, and laptop, you can do it. Lots of people turbo charge other engines, so you might learn some useful things by reading through forums like turbomustangs.com and get an idea what the latest trends are, how people plan, and solve common problems.

 

turbomustangs.com is what got me into turbos i wanted more out of my 88 cougar 5.0 would have been a cake walk compared to this but i may be able to see more out of this engine if done right. thank you

 

Forgot to mention, you may have the problem of the tappet guides coming loose, which caused the gouging and noise. If you search for "tappet guide stakedown kit" you will find more info.

Here is a link about it:
http://www.jag-lovers.org/xjlovers/x...akedownkit.htm

A photo showing a stakedown kit (the allen head bolt simply keeps the tappet guide held down), this kit was installed by Coventry West and supplied on a replacement cylinder head:

This is Alex Cannara's photo. He replaced the head after having a tappet guide come loose and cause catastrophic damage.

The thread about his experience is linked below, and may be helpful to read through:
http://forums.jag-lovers.org/av.php?1158276j01

 

starting to pull the head got everything but the exhaust. my friend is donating a stainless intake manifold and headers that i am designing. and im trying to get ahold of a guy another member pointed me to that did a jag tri turbo but i need to know.
electrically what are my injectors im sure i can find it in my book but high or low impedance.

 

They are low impedance, and there is a resistor pack mounted on the right front inner fender that adds resistance to each injector circuit so the driver circuit in the computer doesn't have to carry high current.

You can measure the resistance of the injectors with an ohmmeter. Low impedance injectors have less than 5 ohms resistance, high impedance have 11-16 ohms. These numbers vary depending on the reference, but measuring the injectors will tell you high or low for sure.

 

thank you well injectors are going to have to wait because i have a cracked head. details on a separate page.

 

update cyl 3 is in need of a bore i'm doing the bore then adding pistons at the same time. im gonna send the crank out for weifht reduction finishing and balance. this project just entered a new world race car specs for every thing.
tracking a toyota 6 speed or a borgwarner six speed. aluminum drive shaft. aluminum floor. this car will not see winter ever again. i will not finish for two years how ever in the spring i will have a nasty snotty engine! keep loosley tuned!