I started a thread in the S-type section on interchanging AJ V8 engine parts to produce more power and no responses. Is everyone preoccupied playing with their FOB making the windows and sunroof open on their S-types?

 

No, us gearheads know when to leave a good thing alone and not throw good money away. You got plenty of good advice on the S-type board but whether you want to listen or not is up to you.

 

Jaguar put a supercharger on the engine and that is where people want to upgrade and spend money. (more cost effective)

bob gauff

 

like motorman said!!

all the cams , pistons, bores and strokes, or anything else, cant match a pressurized inlet manifold!
simply put,just raising the manifold pressure to 14.7psig, is like doubling the displacment of the engine, ah,, like a 3L acts like a 6L.

and more dependable, modifieing engine internals,in todays world, is just old fashioned way of doing things.

 

Heck no, you are not the only gear head around here.

We've got all sorts of development engineer types who go that extra mile in the search for power.

But the current trend is, pressurized inlet.

 

I plan on supercharging my 3.9L but if I can increase the stroke plus use longer rods I'll push more power than just a supercharger. Example if you take a ford 351w put 6.25" rods from a mopar 360 it gains 20-30 hp on a 9.5:1 compression motor. You can also gain 20hp on a fuel injected Chevy 3.1L by putting a 2.8L carberated camshaft in it. 302 Australian cleavland heads on a 351w. I can go on and on. Let's find these same tricks for the AJ V8s

 

You're comparing apples and oranges. The engines you've mentioned are very old school V8s that came in all sorts of HP levels where anybody could take the low perf versions and mix and match factory components to make it into the hi perf version. Your 4.0 engine is already at 11:1 compression ratio. Where are you going to go from there?

 

Increase stroke, longer rods, I can have cams made for it but that's not cost effective at $1000+ a cam that's over $4000 and little gains. My ford dealer says there's a jag supercharger that bolts on to my 3.9 with slight adaption to throttle but they don't know which one any help there? I just wanna combine pressurized inlet with some trick engine work and my tri-y header design and hope for at least 350 hp at the wheels.

 

Well i have 330rwhp from my stock stroked 4litre v6 in my nissan frontier with a mp90 supercharge, brian crower cams, ported heads, titanium retainers, dropped compression and cp forged pistons swinging on billet pauhter rods. At 10psi boost up from the stock stillen 5psi.
All i was looking for was a strong bottom end to handle more boost after i broke a factory piston. Otherwise i would never spend all the money it would take to go that route, its just poor bang for the $$$
and im not even talking about my stroker 383 in the suburban or my stroker 580 bbc in the el camino. There are actually parts avail for those without going custom or 1 off

 

I love the can-do spirit, hot rodding, and more power. But for me, nowadays, I'd rather just go out and buy a car that already has the level of performance I want. There's SO much out there. You can buy mini-vans and family sedans that are faster than the "performance" cars of just a relatively few years ago.

And many of today's performance cars are faster than full-on race cars of the past.

I'm up for a few do-it-in-an-afternoon mods/add ons but beyond that I've gotten pretty lazy in my old age. Shameful, I know :-)


Cheers
DD

 

If you want to 'stroke' your 4.0 (not 3.9) litre engine, just buy a 2002.5 or newer S-type. The displacement increased from 4.0 to 4.2 L through an increase in stroke, bumping HP up to 282. Compression was kept at 11:1. If you want to go supercharged, buy a 2002.5 or newer S-type R with 400 HP. Longer rods (if they were available) would raise compression to an excessive level rendering the car 'unstreetable'.

Jag beat you to the punch on both counts. Buying either of these cars will be much cheaper than throwing money at your existing 4.0.

Wait a minute- this is what we told you on your initial inquiry, wasn't it?

 

I have 3.9L Lincoln LS the jags u mention cost $9000+ if a jag crank costs more than $9000, then I'm done with my jag knockoff LS.

 

The cheapest and most bang for the buck i feel in your case is a sts remote mount turbo kit. Google em

 

Also in south Dakota we have no streetable laws you buy your plates every yr n go I can run any compression I want and fill up with race fuel and drive around the streets

 

Silly me for not guessing that. It's common courtesy on this site to put your car details in your profile. Your engine is the 3,934 CC Jaguar AJ-V8, badged as a 4.0 on the S-type and a 3.9 on the LS. Same engine.

Good luck with your project, be sure to let us know how you get on.

 

Thanks will the turbo kit ruin my ability to make my headers? There's not much room in my engine compartment as is. Also they mentioned jag beat me to the stroke idea. Does that mean I can use the 4.2 crank? Do I even need a bigger engine to get 350hp?

 

you must have a lot of Jag engines laying around, like 4.2 cranks, pistons, rods and stuff!

like brutal said!!

you dont need headers, for a remote mount turbo system, just run the complete exhaust flow into a rear mounted turb. no cats or mufflers,(turbo acts as a muffler).

then pipe the cold air from turb. upfront to throttle body. no I/C.

use a water/alcohol sytem for detonation control. reflash ECU.

use E85 fuel,,and easy 400+hp.

you dont even have to take the engine out!

 

Yeah I like that turbo idea, instead of a collector where I combine the 2 banks I'd put the turbo. The only problem I see is getting the turbo to the intake inlet from there. I don't have much engine compartment room

 

Here's what I'm finding on my stroker idea: the rod journal is very large on my 3.9/4L compared to other stock rods. My rod length is just over 6". I can have my crank offset ground to increase stroke (costs slightly more than a regular grind), use a cheaper rod set that matches desired length and rod journal dia. Now consider this: should you throw a rod bearing on your AJ V8 wouldn't you have the crank ground and rebearing it? The offset grind is only slightly more. One of the stroker options includes Chevy 350 rods, those are dirt cheap. So it looks like I can change my Lincoln LS 3.9L V8's stroke for little money. Mad props to Thomas Knight at boosthead.com he got me all the figures for the stroker AJ V8 and he's the only supercharger kit manufacturer I've found for the Lincoln LS.

 

Not gonna lie, I have no interest in doing anything but regular maintenance and driving my car. It's not a honda civic and I'm not 16, I bought the car to enjoy exactly as Jaguar intended.