nicely done Charlie!

 

Hello. Just wanted to see how the Twin Screw is doing for you now. I have a 99 XJR and I'm considering this upgrade,...

 

Still have a stupid grin on my face every time I get in the car.

Still have the stock exhaust, which has to be a restriction. I've got an X-pipe system to install and plan to get the car re-dynoed when I do, to see what it is worth.

I think there is still a lot of potential left in there. Heads have a lot of porting potential and could be much better matched to the intake than I did in this round.

 

Andre Vos is pulling over 600hp with standard zorst so I doubt this part is restricting flow.

 

How much $ total was involved to get that power?

 

Already answered that one in your other thread...

Not trying to be a jerk, it's just that Andre prefers not to discuss the specific cost of the kit in the public forum, so I will respect that.

It is, shall we say, non trivial by the time you do the twin screw kit and all the other things it leads to.

 

Yes that is true but how much more would it release if he didn't?

I have spoken to the people who built these engines and even they said the exhaust is restrictive particularly the cats but unless you are going to go motoring around over 3000 rpm you will not reap the benefits in any great way......

 

I don't want to speak for Andre but just to set it straight, his car has aftermarket high-flow (200cpi?) cats connected to the factory exhaust. He had a custom exhaust fitted but didn't like it so put the original one back on but left the higher-flow cats in place.

 

Did you know that the Gen II Lincoln LS (2003+?) uses 4-2-1 exhaust manifolds ala
tri-y headers? The guys "over there" consider them to be worthwhile upgrade for
the Gen I installations.

Presumably the Thunderbird does as well.

No idea if they will fit into the available space.

If they fit, ebay is going to be an awful busy place.

edit: probably an easy fit on S-Types since they are
both on the Dew98 platform.

 

Don't bother, they don't flow enough for 400HP let alone 600HP...

https://www.jaguarforums.com/forum/g...-2l-s-c-80560/

 

I have indeed sport cats (200 cpi, think they where made by larini) in combination with a stock exhaust. All details are shown in my profile (Garage - XKR-600):
Garage - XKR-600 by avos | JaguarForums.com

I have had a larger x-pipe exhaust under my car, but it was just too loud for my taste (fun for short drives, but not as a daily driver). It didn't show any significant change on the dyno, but that test wasn't a good one so I can’t say for sure if it would have given me any additional power or not, and next to that it was still with the stock cats. It was also at a lower power setting then the 524 rwhp (am not sure anymore, could have been around 430 rwhp or so).

I have had a 2005 4.2 car on the same dyno before with the TS kit and sport cats with a larini sport exhaust. Besides the tremendous loud noise(really unbarable), it didn't show any significant hp gains compared to my setup with just the sport cats.

Of course at some point there will be a part in the exhaust system that will create more and more resistance (being it the heads/valves, headers, cats, exhaust), and reduces the gains more and more.

I guess also that I would probaby would have a higher result when I went for the 524 rwhp as XKRacer suggested.

Now I am going again for a major power increase (from about 600 to 700), and I have no doubts that at these levels the resistance/back pressure will be much higher again, maybe even so much so that I will not get to 700.

 

Sorry but must've forgot you mentioned this... but I don't get if Dewayne Doe sells a better mouse trap and it's helping clean your house and you're telling us about it. What's the issue with one inquiring about the cost of the new trap that is being sold to the masses? It's only natural questioning.

It's simple, the rat trap 3.0 cost $8.13 cents and I used his bait for an additional $ .30 cents a bag. It cleared my rat problem..

Honestly, I and others are impressed by the gains you're getting and would like to know every little detail on how to duplicate it or at least know if it's plausible for one to even consider. As I mentioned I have $5k and would like a break down vs going to a shop and diy with knowledgeable friends.

Seriously no harm intended.

Juke

 

Juke, I know this might sound crazy, but if you want to know what it costs & how to get it, send an email or PM to Avos and ask him... you might just get an answer too.

 

The reason I don't say the specific price for the twin screw is that I am not the one who would sell it to you, so whatever I say is inherently not correct.

I can say that $5k will get you some nice gains with upgraded pulleys, exhaust, and improved intake. I can also say that $5k is not even half the parts bill for what I have done, never mind the time spent or (eek) if I had to pay someone to do the work.

To get something remotely comparable to a 2010 you will easily spend 5x your budget, by the time you get to similar power, improve the suspension, add a LSD, etc, etc. These are all things you get for "free" with the more expensive newer model.

I wasn't kidding that you would spend the same amount on a 2005 or a 2010.

 

$5k is too less for new 2.6 KB TS kit offered here but is enough to buy used and inspected Kenne Bell/Lysholm/Whipple head unit (or even new bare head unit). You will have to spend few days on adapting it so both your own labour and time is affected.

 

I looked into one of avos's twin screw setups a few years ago and the parts alone were a little under $7k. As a point of reference I spend $5k on my LSD w/ rear axel ratio change (3.06 to 3.27) installed. So, IMHO, for the hp gain, $7k is a good price.


Mark

 

I just think a product being sold should have the price opened to all to assure fair purchase price amongst the members. I'm not saying avos is cheating anyone but having the prices open and ALL the pieces of the puzzle available helps the performance enthusiast as a whole to prevent e-mailing this guy, pming that guy etc...

I think the GREAT work avos has put in our cars is helpful to the community and his knowledge is obvious. Plus I look forward in learning and purchasing some performance products from him.

No harm brother no harm intended.

 

In the time it took you to write that post you could have written an email to Avos and asked him yourself. That's what someone who is really interested would have done anywhow.

Let's not de-rail Charlie's thread any further, if you want to know ask the guy who builds them. It's that simple. No further discussion about prices of Andre's kits in this thread.

/moderator

 

I hear the gear change is very beneficial in the XKR but unfortunately the 4.2 rear set up doesn't have that option. Correct me if I'm wrong. What type of results are you getting with the better rear set up?

Also thanks for giving us realistic cost options

The KB kit seems like the route but I guess I must allocate a few more pennies towards my car perf fund. I'm handy but I'll be afraid to year into the SC system on my car.

 

@Juke,
Have just send you a PM.

@Krajock,
There is a big difference between making adaptor plates and the kit I offer, to come close in power levels/efficiency you need to do much more.