Have not had any issues with the x100/x308 pinions (and clutch based diffs like my os giken), but that could be because I have given it a shotpeen treatment.

The other issue is with bearings, where I had a couple of occasions that cost me to replace them and gearing (as once the bearing go and the diff makes noise, they need to be replaced as well).

My 1st issue with bearings was when I actually had the quaife unit, just after 10Kmiles or so.

Considering that the x100/x308 diff bearings are larger as the x300/xjs diffs, I wonder if these units would be the better option…

 

Do we also have the rear end issues with the LS swap? A stroked LS does about 410RWHP, 370 rwtrq.

 

Unfortunately we are stuck with an 8". That being said bunch of my modified buddies have their gearsets cryogenically treated and has seamed ot help them with wear and strength issues. Also there are coatings you can have applied that help with wear and friction in general. Why not look into these options while you are at it.

 

I have a question for users utilizing their twin screw setups. Is extra power felt right at once after first after-mod start up? I know ECU needs lets say 100 miles to adapt but is this time needed to learn proper and safe AFR or build extra hp? Or both factors?

 

You will notice the difference the first time you step on the gas. You will think it is a different car.

 

Yup!
That's about the best description.

Jeff from Tucson did a video of his first drive out of a car park with his new twin screw setup. That video sums up totally the answer to your question.

Once fitted you have the jaguar that Jaguar should have made, from the start.
Stunning!! Addictive!! and totally wonderful!!

I wish I could share with everyone what I now have. The looks of the original car with today's performance.

Do it!

Sincerely,
Colin.

 

I'm sorry but posted videos show nothing to me, just crusing. Would love to see onboard movie with acceleration 0-100 mph or for instance 60-150 mph.

 

I know you are trying to making your own twin-screw conversion, is it that you have an issue with your setup, or what is it you are after?

 

I managed to complete instalation of KB 2.2L unit. TB and air box are stock. Bigger IC heat exchanger and additional HE under the bumper. Hella and Bosch 010 pumps in series.

At pulley ratio 2.26 car reaches 15.5 psi of boost (IMHO to low as for 2.26 ratio), but I don't feel performance improvement. I don't think it is over 400-420 engine HP.

I'm planing to check AFR tomorrow.

What PSI numbers do you see with 3.25 pulley and 2.6 KB?

 

20-21psi

 

One 4.0 with stock TB and MAF, 1.96 pulley ratio: 522bhp with AFR 12.5 and 519bhp with AFR 11.5 , both at 16.7PSI. Bit restrictive intake pipe at that time. Another 4.0 with stock MAF but bored TB and better intake tube/filter with very low measured vacuum at 20PSI ( same pulley ratio ) has made 30-40bhp more based on the 1/4mile results.

 

On one of my early prototypes with the 2.1L twin-screw version, stock TB and MAF and a ratio of 2.35 gave about 16 psi (ish), and 455 rwhp.

PS Why not resurrect your old post for this?
https://www.jaguarforums.com/forum/x...rmance-131417/

 

Avos, XJR-99, thanks for your input. I didn't want to hijack this thread, just wanted to ask about boost you get as its popular KB mod thread.

Seems my 2.2 is pushing enough amount of air (according to boost I get). I'll check the fuel system, it may be unefficient.

 

Its not my thread and your question was ok to ask here imo, I only suggested it as you started a similar quest earlier in your own thread, am sure that you get responses there as well.

 

Jaguar Other F Type s 5 0L V8 32V | eBay

Just be careful with all that power

 

The most interesting point for me is, how fast is the car from 100 - 200 kmh.
My stock XJR (just upper 1.5lbs pulley) does the sprint in 14.9 with 2 Person inside (about 230kg) and 3/4 fuel, 21°C outside temp, no a/c

I think it will be faster if the outside temp is much lower and no passenger.

Regards
Maxi

 

500+ bhp xkr/xjr should do 100-200kph in 8-9 sec.

 

That would be a good point to start!

 

Being I got over 400rwhp with a 1.7 liter Autorotor on a 3.8 v6.....Id say the 2.1 should get you at least there. We have a guy in my other club running a 2.1 big bore I believe it was making a tad over 500 to the rear wheels with a 4.2 v6....Granted ported heads and a cam....But we are talking boost here! I personally cant wait for my twin screw kit from Avos....:O)

 

I need an avos twin screw kit in my life where do I find one?