Hey y'all:
so, if I'm gonna be tearing-down and doin' a freshen-up on whatever replacement motor I buy, I figure I may as well look at any easy mods while I'm in there.

But here's the thing: I've never owned a forced-induction motor before (I know: weird, right?)

What will this motor respond well to? Should I spend any effort porting heads? Any lightening of the rotating or reciprocating masses that this motor benefits from?

I'm not looking to build something crazy, and I don't want to lose sight of the bang/buck ratio. In other words: I only want to do mods that will be NOTICEABLE.....

What, if anything, would y'all do?

 

Count Iblis mentioned the combustion chambers had some special shape devised by an Austrian consulting company, that really didn't help much. Have a search through his posts, if you have the heads off that might be something to look at. For internal mods Count Iblis seemed to be the man.

 

Be sure to replace the hose under the SC and check condition of EGR piping.

 

Maybe not internal but.......

 

Lol. Rick, originally took your nitrous as a joke, but this faded and became a possibility. Mcjaguar's, the heads are already excellent in flow and dynamics. Save the mod money for the soon to be released avos twin screw kit that alone equates to 150-200 chp. Or do what I did for an est. 60 chp gain.

 

Sounds like the Twin Screw is my ticket.

While I'm rejuvenating the motor: any Nickasil or Nitriding that will keep me from using normal machining methods on this motor?

 

I was was gonna second or go first bf's recommendation. On forced induction anything other than reliabilty improvements. Any money spent on anything else is small return spent for the money

 

Yup, if you're looking for noticeable gains on the cheap as far internal tweaks go, you won't find any worth the hassle,

At most, if you're going to have the rotating assembly apart, I would consider doing some high-tech coatings on the pistons, bearings and bearing contact surfaces, such as WPC treatment,

Although this won't produce power gains per se, this is good insurance on some engines, although the cost of said coatings very well disqualifies it from your 'bang for the buck' criteria,

The avos TS kit is our one and only coming salvation...

 

If you are ripping it all apart, I think this would be a good time to bring it up to par with standard jaguar specs, at least it's my understanding that the standard motor was quite stout. While you have it all ripped apart, I would consider this an opportunity to employ a chiller killer set up along with a 3lb. That should be enough bang for buck for a $1k investment.

 

thanks everybody, for your comments.
I think the Avos Twin-Screw is in my plans.

Can anybody confirm for me if the '03 STR 4.2 has Nikasil cylinders or not? I've searched around and found plenty of information from those who like and those who don't, but no definitive source for which do and which don't have it.

TIA

 

No Nikasil in your engine McJaguar.

 

Only the 4.0 had the Nikasil cylinder liners. Like the Eaton M112's 1.9 L diplacement, an Avos 2.4 L TS is a positive displacement blower that effectively increases the STR's 4.2 L to 6.6 forced-inducted litres: est. 600 chp @ 550 lb/ft trq.

 

I think Avos uses a 2.6 Kenne Bell SC.

 

2.6 L ? Wow! That's a friggin large displacement blower. Then the 4.2 L becomes 6.8 L with an Avos 2.6 L TS blower. With this much forced inducted positive displacement, there shouldn't be no mystery as to why the Avos TS 4.2 L makes 600+ chp. Read the 1999-06 XK-XKR forum's thread: "Another Avos Twin Screw Conversion". The Arizona, USA based OP popped a 4.2 s/c with an Avos TS (Kenn Bell 2.6 L) into his 2000 XKR and is starting it today with vids w/sound.