Those were the threads I was going to direct you to....

Regarding the VVT I don't know if anyone as done it with the AJ28 but with an AJ33 or AJ34 you can delete the VVT by swapping the cam sprockets to the non-VVT version. The cams themselves are the same for VVT or non-VVT. A quick check of the parts catalog confirms the 4.0L N/A cams from the S-Type are the same as the 4.0L S/C cams from the X308 XJR.

Download a copy of the Jaguar Engine Repair Course Code 168, this details the basic changes from each model year on the engines.

And download the S-Type Model Introduction Launch document, it details a lot of design features of the engine in question.

Sounds like an interesting project, definitely NOT impossible and probably made quite easy if you are running a full aftermarket ECU and a manual transmission.

 

In reading the two links, one owner dialed back the boost considerably and the other ultimately substituting a low compression engine each to avoid (at a minimum) detonation issues.

Neither project came anywhere near the desired 450HP and probably made not much more than a stock unit.

I'd get the car running in NA mode first before playing around with supercharging. A case of putting the car(t) before the horses, so to speak.

 

It's going to take quite some experimentation, but sounds like he's up for it.

One thing is: after the SC something must be done to get the charge air temp down - the STR etc use intercoolers, for example, and an IAT2 to tell how well the temp has been kept down.

I'm guessing member avos may be interested and perhaps willing to comment.

 

Thanks for all the info chaps!

If it makes 350-400bhp in version 1, then 550 is definitely on the cards fo version 3...



First job is to get it running reliably and do some track day shakedowns...
After that we can start upping everything until it goes bang, and I will get a 2nd engine to build fully blueprinted and lightened for version 2...(probably aim for 9:1 ish for compression ration on the 2nd atempt.)

 

Also remember if it makes 375bhp initially that is 416bhp/tonne!!
That will be damn rapid!

Also bare in mind that I don't have to run cat's which I have heard can be worth 20-25bhp?!

 

It's not going on UK roads? If not, you've certainly got more options.

 

It's a 1987 chassis... Doesn't have emissions test to pass
Previous engine didn't have cats either...

Means I can remove them

 

The INTAKE cam CMPS reluctors are VERY different from AJ26 to AJ27 to AJ28

AJ26= 1 lobe for the CMPS
AJ27= 4 lobes for the CMPS
AJ28= 5 lobes for the CMPS

Exhaust cams are probably all compatible.

You could install the correct CMPS reluctor lobes to make them work????
I have never tried this.

bob gauff

 

An insurer is going to love you. £2000? £4000?

 

Classic policy... Includes track days and agreed value of £8k - £260 per year.
It's tacked on to the fleet policy for all the other cars I have! Lol!

5 cars for my wife and I cost just under £1000 per year with free breakdown cover. Can't recommend herritige highly enough. I even get an account manager whom I email whenever I change cars (which is quite Often! There's so many cars I want to have owned and drive!)

 

It's not truly a classic just because it has an old chassis (body). Your project would be a highly modified car which you would have to explain in detail (in effect you have to read the insurer's small print with their lawyers' eyes). I expect a huge hike in premium.

I think you'll also need some sort of official certification that it is road legal (maybe from VOSA?).

I think you won't need the latter if it's never for use on any UK road (e.g. track use only).

 

I did check with them and I have to send pictures each year when I re-insure it.
It doesn't need a VOSA cert.

 

Check with them? You mean you detailed that you'd be changing all the safety-related stuff (*) and putting in a far more powerful engine and they don't want any more money? Get it in writing!! (**)

Obviously, the car has to be roadworthy and if it were found not to be following an accident (I'm thinking worst case here) then you face bankruptcy and jail

I don't want to put you off, though. Quite the opposite - it's a great project but needs doing right. Quite likely you know all this but just wanted to make sure...

(*) er, you ARE doing that I sincerely hope!

(**) I do mean that - a conversation is not going to be binding

 

yep they have been send images of the build, specs of the FIA roll cage, the 6 pot caliper details with brake compounds and disk sizes, photos of they car they have on record (it used to cost me £165 a year including track day cover with all the suspension mods, brake mods, twin-45 carbs, supersticky R888 tyres etc. on a 7500 mile limited policy) oh and the excess was only £150 on the road, and £1150 on track too!

don't worry its all in hand!

somewhat off topic...

so regarding Cams would i just need to change the inlet cams? i would prefer to delete the VVT for simplicity's sake... i did wonder about using the VVT open at low revs to improve torque and non VVT at the top end to improve power... (opposite to the NA car) - Honda did this on the new Civic Type R, the VTech now kick in under 4000rpm to improve low down torque with the new Turbo engine, totally the opposite to the old Honda K20 which wouldnt hit VTech until 5500rpm plus...

any help appreciated!

 

The STR already has torque that easily spins the (275 wide) wheels off the line. Are you changing the diff?

 

From the new member section post:
(Sorry I thought this was repeated in the other post I copied into this thread)

 

Yep, that'll definitely spin the rear wheels so I hope that diff is LSD.

The rear wheels look far too thin...

 

Wow, what a great story! I really looking forward to learning how it goes. Please include as many pictures as you can. I'd really like to see the engine compartment, first with the old engine in place, then empty, then... :-)

================================================== ===========
Understeer is when you hit the wall with the front of the car
Oversteer is when you hit the wall with the rear of the car
Horsepower is how fast you hit the wall, and
Torque is how far you take the wall with you

 

Best of luck with the project from an owner of one of the last 50 Lotus Elites imported to the US. You are addressing its only flaw.

 

i think i can do the first 2...































and the donor car i paid £1100 for and stripped for £1800 and kept the engine!