So, i took the pulley and instructions to local sport/hot rod shop, they said it would probably be about 2 hours of labor to cut it off?? So they can be extra careful they said. ??? Should I just buy the instal/ and removal tool for that pulley would I save money having them do it that way. I wish I could do it myself but not to that caliber yet, working on it.

 

It would be more economical to let them cut the stock pulley off...I rented the Eurotoys puller, which required loosening the motor mounts and jacking up the motor...the mechanic and I looked at each other, and together we both said: "Cut it off". You can go one bit further by just removing the supercharger and sending it to Stiegiemier for porting ($450) and fitting of the 1.5 or 3 lb pulley on their new water cooled front blower housing ($450). This route is worth 50 rwhp and minimizes heatsoak. ECU tune ($995), Mina intake ($135), ported blower ($450) w/3 lb pulley ($175), hi-flow cats ($160/pair), and Tru-X center muffler ($100) are worth 75+ rwhp. One day we're going to have long tube headers and a LSD. Regardless, the 1.5 lb pulley will move the powerband lower on the rpm scale; was my first major mod.

 

Bfgross, I am on my iPhone right now but the dyno thread posted by another forum member shows no top end loss with the 1.5lb. I will try and post the comparison graphs this weekend when I have time.

edit in bold

 

Eh, you might have read it wrong, he says it 'moves the powerband lower', so you pick up more low end power with the pulley. From the dyno's I've studied, seems like the pulley's power gains above 5,000rpm are pretty small if none at all.

The eaton simply can't flow enough.

 

GT42R, Exactly. A smaller pulley brings the power on lower (earlier) in the RPM range. A port/polish of the blower, modded intake and exhaust, and ECU tune dramatically helps with the blowers self-limitations.

 

I paid a local shop that specializes in building full blown (literally) domestic quarter mile dragsters $360.00 to install my 1.5 lb Mina Gallery pulley, but they also did some other small things that I can not recall that my car needed done. If I had to guess, it would have been around $250.00 or so just for the pulley install.

 

$250 is a good price!

 

Check out the info from goblue90's dyno thread:

https://www.jaguarforums.com/forum/s...-thread-79842/

See the two dyno's below, with the top dyno showing the results of the 1.5 pulley. Notice how the peak power stays the same at about 6000rpm, but he sees a gain of 16rwhp at the peak. My point is that the 1.5 pulley provides top end too, without pulling the powerband down, meaning peak power is not at 5.5K rpm, instead it stays the same.

 

Rasputin, excellent example of a 1.5 lb pulley dyno comparison. The power comes on earlier and stays.

 

The problem with "pulling" off the blower pulley is that there is no room to get puller on and the pulley off without raising the motor to clear the radiator. It's just a ford mustang cobra puller / same blower. Cutting it off is easy if you know what you're doing. the Best way to do it is not exactly to cut it completely off.

Picture the pulley as a clock. You need to make two cuts about 2/3 to 3/4 of the way through. One at 10 o'clock, one at 2 o'clock. Then take a chisel wider than the puller and a big fat hammer (yes that is a technical term), or air chisel, used as a wedge, and split the pulley the rest of the way, on both cuts. You do not want to cut into the blower snout.

Pressing the new pulley on is easier. But getting it absolutely perpandicular, and straight on the shaft is critical before you try to brute force it.

Personally I dont care for the 3lb pulley. I think it overtaxes the blower, and I don't like the idea of machining the snout.

Seth, where are you getting all these hp numbers? Best guesses? Butt Dyno?

Hp doesn't matter as much as torque. Hp = max mph. Torque = how fast you get there... That's the fun part.

Look at the two dyno graphs, and just look at the two torque curves. THAT's the benefit of the pulley. Max torque sooner, more torque, and a flatter torque curve. That's why Seth's butt dyno claims it moves the powerband lower. BC the car FEELS faster, and the "power" comes in sooner. But it doesn't move the powerband. The hp and torque curves still cross at the same RPM. What it does it expands the powerband into the lower RPM range, as well as giving a modest increase in power.

Take care,

George

 

The other problem with trying to pull the pulley off without cutting it is that it is nearly impossible, even with a puller. I cut mine down in slices as androulakis said, except I went down further as I didn't want to chisel/pound away at the snout at a high angle. Installing it was going well until the tool broke. Either way, as I've stated before, if I had to do it again I would pull the whole supercharger out and send it out to get ported and the pulley installed at the same time. It was more than a hassle to do, but if a shop is willing to take it on, I would've paid someone else to do mine as well.

 

George, 3 years ago this coming spring, my intake and exhaust modded 03 STR was dynoed at nearly 360 heat soaked rwhp (335 rwhp stock), 17% parasitic loss= 425 chp. Since then added was: 3 lb pulley, Mafioso air intake tube and Mina inrake. The opening of the intake has made a more than noticeable improvement in throttle response and improvement in the Butt Dyno dept. As you may be already aware, the 400 chp STR is plagued with intake and exhaust restrictions. The enhancements and rectification of these likely unleashes 50+ chp. When considering the means of opening up of the orifices of my 03 STR, it's reasonable for one to assume that 400 chp has transmutated into 460 chp. Long tube headers would be the coupe de gra in nearly reaching the 500 chp mark. In other words, my modded 03 STR runs like stink. The 03 Audi 4.2 Turbo belted out 450 chp with just a little less credentials.

 

That doesn't sound like a bad idea to pull it out completely and have it ported/polished. Will those people install your new pulley on too?

 

I'm not sure on this, but I think stiegemeier charges $695 for a blower rebuild, and if you include the new pulley, they won't charge more for it's install.

Their porting will be another $495.

That's $1,200 right there, plus another $200-300 for a pulley.

Not sure if its worth the cost for what might be only 20-40hp in gains. (although you likely wont make those gains anywhere else once you've got most of the bolt ons covered)

Might be better to bank the $1,500 toward an avos twin screw kit. Although with that being $5k+, idk how much financial sense holding out for that one makes either.

 

Yes. Eurotoys is right around the same pricing as stiegemeier, although the pricing is built a little differently. I think they do the porting/pulley combo and charge more for a rebuild instead.

I have a few issues with the potential TS kit: 1. We may never see one. 2. I have a lot of respect for what Avos has accomplished with the XKR. However, there aren't a lot of documented TS XKRs running around with dyno and/or 1/4 mile results. We don't really know exactly what we are getting. 3. The kits just aren't proven. They haven't been out long and one of the few (two?) XKR members who purchased one had issues with it. Avos rectified it quickly with great service, but the fact still remains that there was a problem to begin with. Perhaps the next time it is a catastrophic engine failure. It may also make future engine issues harder to diagnose as we won't know if problems are related to the kit. 4. Unless I'm mistaken, it isn't going to be a plug and play ordeal. One must make permanent modifications to fit the kit in (at least for the XKR). Some of us might have problems with that, some might not. Personally, I don't care. I've already machined the snout on my Eaton for the 3# pulley. It more so depends on if you plan on keeping your STR forever or not. If we do get a twin screw and install it, I'm sure you will want to. 5. Cost. XKR kits are rumored to be in the $6-8k range, plus shops quoting around $1500-2k for install. You are looking at ~$10k for a mod on a ~$10k car. 6. We still won't be able to dyno tune. We can't even get a real tune for cars with an intake or a pulley!

 

I agree with your general sentiments, as I am very sceptical about these sorts of offerings myself, i still hold a lot of reservations, however...

1- We may never see one - I thought so too until he shipped the first few to XK owners. Now he is reportedly doing an STR car; I we see something... eventually.

2- Not many running examples or much dyno evidence - Also a good point, but avos seems credible and competent, and the components appear professionally designed and machined, one reported hiccup this early in development is growing pains, custom-anything in the aftermarket has its issues; whats important is the support,

3- Engine failure, voiding warranties, making permanent modifications, long-term ownership - well this is par for the course and i really can't fault anything about avos' twin screw kit in this regard.
I don't think anyone is under any illusions here, a twin screw kit is a major investment and overhaul to the car. When you go this deep, you have to be prepared for there being issues and compromises.

The beauty of the TS kit is once it bolts up and seals properly, it functions a lot like the stock blower, and does not interfere with the rest of the engine and its management system,
at this point, you have to be prepared to approach it responsibly with some tuning and datalogging experience, to monitor and determine if things are operating safely and reliably. That's a significant boost in power, and you'll start testing the limits of your factory cooling system, engine, transmission, fuel system, electronics, all potentially leading to 'catastrophic failure' but hey, thats a reality of modding anything, mild or wild.

$6-8k is a lot of money, I was thinking (wishfully) a basic kit would be around $5k. Indeed, installation and setup would be even more, as well as having an experienced tuning shop go over everything even datalog/tune in some fashion.
For me personally, i do all my own work/tuning/etc, so if avos' could ship me a TS kit that bolts up to my intake manifold and throttlebody and pulley, I would handle the rest from there.

I have modded and tuned many cars, and I would be perfectly comfortable to flow an additional 100-150hp in my STR on factory everything with just a meth injection kit.

A tuning solution for the factory electronics is indeed non-existent, but the case has been made that the factory electronics will handle an additional 20% improvement in peak air flow, so if you provide the air, the hp will come. A twin screw kit bumping 100hp could likely be managed fines, a tune wouldn't make or break anything in that regards,

A tuning solution will become a lot more important once your start reaching 100-200 and beyond HP gains,

 

@QuartzStyper
Have just updated my main thread, am now speaking with the manufacturing company to have a 1st set made for the STR.

There are a couple who have done dynos in the UK (NormanD for example), but I don’t have the dyno slip, but the majority with the kits aren’t active on the forums. Here are 2 that are in the US:
https://www.jaguarforums.com/forum/x...special-87207/
https://www.jaguarforums.com/forum/x...-4-mile-83228/
(This is just the start, he is still having the 75mm tb and maf, more to come here…)

And another interesting to follow:
https://www.jaguarforums.com/forum/x...kit-usa-82598/

You have also probably found several posts from Jgaxkr, he has the Stage II kit on his XKR, and he has had all the mods you can think of on the old eaton setup, and is more than happy to let you know what the difference is with the twin-screw setup.

On the XKR I use a different TB fort the Stage II kit, which requires also a separate control unit, to match it with the Jaguar electronics. Have tested myself the final unit for about a year, before I made it available to others.

The owner wanted to have the unit quick, so I had send the unit straight to him before first to me for testing, and unfortunately my manufacturer had updated electronics (with good intend) without telling me, which didn’t work out.

Have learned from this, and never send out anything direct anymore, and test/match the parts 1st. That was it (almost 2 ½ years back, and many kits ago). Please also note that I have been very careful before I put it to marked, I have done years of driving actually, and have now more than 140Kmiles TS experience on my own car. So that you highlight this particular part as “fact remains there was a problem” doesn’t do justice imho.

Agree with the GT42R comments here, although I can’t comment on the price rumors, also as I don’t know yet what the costs will be for the str.
4- Not sure what you mean by permanent change, anything can be reverted back, and am sure you will get a good price for the kit if you want to re-sell, but most I know that have bought the kit have a passion about their car, so chances are small you will see a 2nd hand unit for sale.

Last but not least, don’t hang yourself up upon a ECU tune, mine is still stock. With the kit you are able to make use of the reserves build into the ECU, only if you go outside of that could a specific tune be helpful again. But for the power range expected its not needed. On a stock car you can take advantage of the reserves, which is where you get the extra power, but such a tune couldn’t be used anymore for the TS kit if you see what I mean. Next to that there are some small tricks, but all depends on the boost you choose and what other mods you have.

 

I would say let's just be thankful that there is anybody doing R&D and considering marketing mods for such a niche vehicle as ours. When you look at STR production numbers, filter out wrecks, non-performance drivers, attrition of an aging 5+ year old platform, how many units can one be expected to sell?

 

I agree, its nice to have someone at least taking a shot at this. It is also nice that they take the time to address concerns and still back their products.

Avos: My point about the ECU tune was more to say that a "basic" tuning function is still missing and we could be leaving a lot of power on the table with or without a twin screw setup. Thanks for taking the time to address my concerns. I hope you don't view them as anything negative as it wasn't meant to be, more just thinking out loud. I thought Jeff in Tuscon had mentioned needing to cut, reposition and re-weld intercooler connectors to fit the twin screw? I understand about not wanting to get into pricing publicly, you designed the kit and rightly should be able to price it as you see fit for all your R&D time as well as parts cost. Keep us updated, I'm sure there are several seriously interested members.

 

Doesn't monitoring AFR provide crucial data as to whether any tuning can be done?

I ask because several people, including avos, have monitored AFR and found that the car runs somewhat rich during WOT but that is something that is wise.

Is anyone really wanting to cut the richness?

What am I missing here?

On non-tuning, it seems people would like DSC fully off but that's not a "tuning" issue.