ajm55

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First-off, I live 5,500 feet above sea level. The performance-data provided below should be viewed with this fact in mind.

Prior to the installation of the Weistec unit, I was running the following mods: 168 mm crank pulley, smaller upper pulley, long tube headers, decat, 82 mm throttle body, EC heat exchanger, TTM looped rail and injectors and one-step colder plugs. Let’s call this "the previous set-up".

On installing the Weistec unit, the smaller upper pulley obviously came out as did the TTM looped rail and injectors. We also split the cooling and installed a trunk tank.

The power

Weistec was at all relevant times fully aware of the altitude factor, my previous mods and the power my vehicle made from inception (in stock form) through to the installation of the last of the pre-Weistec mods.

In considering the purchase of the Weistec unit, I was alive to the fact that their test vehicle was run at sea level and that I could not therefore expect the same numbers. I was not, however, prepared to purchase the Weistec unit without a guarantee from Weistec as to "absolute minimum" gains. To this end, I imposed, as a pre-condition to my purchase, the requirement that they warrant that at altitude running long tube headers, an 82 mm throttle body and their unit, I would see an ultra-conservative absolute minimum of 495whp. They assured me that I would "easily" get this return and added that a car equipped with their unit dynod at a location situated over 4000ft above sea level made only 20hp less than their test vehicle – i.e. around 560whp.

On the previous set-up, we made around 420whp and 665nm on pump gas. Running octane booster on the previous set-up yielded results ranging from 425whp to 431whp. The Weistec run referred to below was, however, on pump gas and using an "apples for apples" approach, the octane-boosted runs are, therefore, best ignored.

The pre-and post-Weistec installation runs were done on the same dyno on different days but in similar conditions.

We only did two runs on the Weistec set-up. On the first, we made 470whp and on the second 472whp. Torque on both was around 697nm. The tune itself was very conservative.

The end result was that I was about 50whp and 30nm up on the previous set-up - singularly unimpressive but more importantly, significantly shy of the warranted "absolute minimum" performance gains.

I should add that these numbers were achieved with the car making close to 17 PSI of boost until high up in the rev range. We managed to get to 17 PSI using a 54 mm upper pulley together with my 168 mm crank pulley. So, as I understand it, the car with this pulley combination was boosting close to what their test vehicle was boosting at sea level notwithstanding the fact that I'm at high altitude.

Another disappointing feature on the Weistec unit was the power band. It bore little resemblance to the dyno graph depicted on the Weistec website. Between 3,100 and 3,500 rpm, the car showed a dip in power and a significant drop in torque (97nm). What's more, the power dipped quite sharply from about 5,700rpm whereas on the previous set-up, power would be maintained up to about 6,000 rpm.

I'm waiting for my tuner to e-mail the dyno graphs to me.

IATs

IATs on both dyno runs were acceptable - can't recall exact numbers but not more than 70deg c. I’ll get the details from my tuner.

However, the IATs on the road were problematic from the outset - significantly worse than was the case on the stock unit, except in one respect which I refer to below.

For the sake of completeness, I must point out that initially the trunk tank was plumbed in a different sequence to that suggested by Weistec. We had it as trunk tank – h/e – intercooler – bosch pump). My tuner maintains that this sequence is perfectly acceptable as the water is at its coolest coming out of the h/e. Nevertheless, on Weistec's suggestion the sequence was, to the best of my recollection, re-routed to trunk tank – intercooler – h/e – bosch pump.

Another "transgression" on our side is that the inside diameter of the piping running beneath the chassis, as originally set up by my tuner, was only 12 mm. On Weistec's suggestion, this was also corrected. The system was properly bled.

It makes more sense for me to tell you about the IATs as experienced after the aforementioned two errors had been remedied.

We work in Celsius and not Fahrenheit here so the numbers that follow fall under the former measurement.

The IATs at idle and in the course of casual driving tended to climb to an uncomfortable level fairly quickly. The kind of thing I would expect would happen if the bypass valve was closed at idle. Generally, after driving at moderate speeds for 5 minutes or so, the IATs would escalate to anything from 23 to 40°c above ambient (depending on whether I was in bumper-to-bumper town traffic or cruising on the freeway). Once they settled at a particular level driving at moderate speed, they would not dip below that level except perhaps by a degree or two. These levels are significantly higher than those seen with the stock blower.

Because the starting-point was always so high, the end-result when going WOT was also significantly higher than on the stock blower.

On the plus side, the increment while going WOT appearred to be marginally better on the Weistec unit than that produced by the stock blower.

On the street:

I managed to do a few runs before the motor popped - all against a mates E55. His mods - 190mm crank pulley, 82mm t/b, LTH, full exhaust, split cooling, trunk tank, EC h/e. The long and the short of it - there was little to
separate us.

Conclusions

Ultimately, no viable explanation has been proffered for the low HP numbers and the issue concerning the inordinately high IATs at idle or with casual driving was never resolved.

As most of you know by now, the car's going under the knife so there'll be nothing to report on the performance front for some time.

The one plus (although not everyone's cup of tea) is that the Weistec unit sounds fantastic when going WOT - it's quit addictive - but in my case (I obviously can't speak for others) I've had to fork out a small fortune for a scintillating whine and a little more power.

Would I recommend it? If the gains I saw are all that one should expect, then no - especially not at the price. However, if my unit was uniquely problematic and not reflective of the blower's potential when functioning like Weistec says it should, then perhaps.

Hulk

Hey bro, when the numbers that were promised by them were not achieved, did you tell them and ask for a refund before the inevitable happened?

ajm55

I held back on pressing Weistec about the numbers because the IAT issue intervened. It became all-consuming and needed to be resolved first. I will however hold them to the guaranteed numbers once I'm up and running again - assuming of course I muster the courage to stick with the unit.

hpV12

If not, I get dibs on your kit.

ajm55

You top the list

PACougar

AJM, Have you tried turning on the IC pump with a hose disconnected to verify actual flow through the entire setup? It'd be nice to see the amount of water that's flowing both through the IC and the heat exchanger.

e55amgrocket

Prada doesn't need it send it to me ill take it

ajm55

My tuner did a lot of testing in my absence, so not sure. I can tell you that the flow into the trunk tank from the IC pump was very strong, especially once the 12 mm ID piping was substituted with the larger pipe. For what its worth, the increment in IATs when going WOT was better than on the stock s/c. I assume that's a function of the bigger more efficient IC. Is it possible that with too healthy a flow, the water will move through the h/e too quickly to achieve optimum cooling?

AMGPilot

Yes

Hulk

Not with a Bosch pump

PACougar

I'd like to know how the flow was coming out of the IC? I seriously doubt with only one pump you were pushing too much water through the HE. Lot's of us are running two pumps without that sort of problem. I personally prefer a pump in front of the HE pushing through it.

ajm55

I'm going to resort to a secret bidding process

There's a rule 2000 bilge pump in the trunk which was generating a really healthy flow

Hulk

The rule was in the tank, correct? If yes then the Bosch up front is still not fast enough, guys have a mez and it's fine, so I highly doubt the Bosch was pushing the water too fast for it to cool

e55amgrocket

Let me know the secret bidding process and we can keep it a secret between us lol.

hpV12

Lol! How about we race for it?

urbamworm

I am not completely sure how the Weistec intercooler is setup, but it could be just one pass straight through with the water/coolant. The stock intercooler is a triple pass with a lot more restriction having to divert the water back and forth through the intercooler as it goes from one side, hits the end tank, does a u-turn and heads the other way, hits the end tank, does another u-turn then works its way on out. The inlet/outlet of the stock intercooler coolant path are also pretty small at roughly 1/2" in diameter.

So 2 pumps trying to force water through those tiny passages and with all the u-turns within the core could cause not as good of flow as one pump through a 1 pass core.

This is what ours looks like, pretty ****ty if you ask me, especially when the same water is used to "Cool" the air as it gets hotter and hotter making 3 passes through the core.

Look at how small that hole is water travels through.





And the chambers can be seen from this and the other endtank

Denroll

^If these two a-holes crash out (the two above urbamworm), I'm next in line!

PACougar

Great point David, that's why I'd like to know how it actually flowed through the Weistec IC.

Zod

well, lets put it this way, power is not what you expected...but then again the numbers with all your mods you listed, is what most of us are used to seeing stock 410-430whp

You made that with all the mods that can take you up to 500-530whp

so in essence the numbers you are making fit as they claimed 570, and that is right around what you gained 50-60 whp give or take going from 420 to 470

Hope it all works out for you and am glad you are keeping it constructive

Das Geld 2

All that work for such minimal gain...I still don't get why people take off a perfectly good S/C to put on another S/C.

This Weistec SC is ideal for the 6.3 platforms.

e55amgrocket

Hey now a-hole don't be trying to get into this group of secret talks now. Hopefully we don't have to race for it now because I think you will take us at this point lol. At least you know how it is being without your car. Kinda funny the 3 guys that have gone thru/going thru motor builds or blown motors are all after this blower. Boy we are smart

Denroll

Like they say, more dollars than sense, lol.

e55amgrocket

Ain't that the truth.

BlownV8

What were your AFR's toward the upper RPM range. IAT's can be made much worse when you are running lean. A lean condition is a good opportunity for pre-ignition and that will destroy a boosted engine in an instant.

I would have all your injectors flow tested before reinstalling into the new engine. Did you inspect the plugs after the engine blew?

hpV12

Lol way I say I'm already in it probably more then it's worth why stop now? Where everyone says the limits of this engine are maxed, I say the fun is just beginning. And yeah... My Weistec if he sells. He already said so