Europroducts chip set with LBE. Are shims required?
10-17-2002, 03:06 AM
#1
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Europroducts chip set with LBE. Are shims required?
Hello, I have a 87 951. I recently purchased a set of chips and shims from Europroducts off of Ebay. I was wondering....Can I use a LBE instead of installing the shims that were supplied with the kit?
Also if I could use the LBE without the shims, what should I set the boost at? My 951 is completely stock right now and I will be adding a high flow cat and exhaust.
Thanks in advance!
Also if I could use the LBE without the shims, what should I set the boost at? My 951 is completely stock right now and I will be adding a high flow cat and exhaust.
Thanks in advance!
10-17-2002, 03:15 AM
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Not that I'm an expert, much less a guru on this - but I have read about a thosand threads relating to just this. You'll want to shim the wastegate w/4~5mm shims and use the LBE dialed back a few threads (to about 8psi). This is actually one of the safer ways to go when bosting/chipping your car while keepign the most boost with quicker spooling.
There are several good posts in the archives (not that I can find them right now) dealing with just this issue. Or maybe someone else will post the specific/technical explinations for you. Good luck.
There are several good posts in the archives (not that I can find them right now) dealing with just this issue. Or maybe someone else will post the specific/technical explinations for you. Good luck.
10-17-2002, 03:55 AM
#3
Since you have a '87 you must use shims.All '86-'88 (220hp) Europroducts chips come with shims.If you do not use shims, you will not get all the power.I use Europroducts chips (with LBE) and i am changing them to Guru Racing's chips.Europroducts chips have problems with higher revs; mixture is far too lean.I have also noticed the midrange is much too rich.
10-17-2002, 03:54 PM
#6
Race Director
"I think that's the shortest post I've seen from you. Feeling ok? "
Ok fine! Here you go:
<img src="http://www.gururacing.net/ImagesMisc/WastegateStockManual.gif" alt=" - " />
In the stock configuration, there are actually two forces managing the wastegate and therefore your boost; pressure from the boost-controller and exhaust-pressure (it's actually on the BACK of the valve, I mis-labeled chart). You have to add up the sum of these two forces in order to understand your boost-curve. Even with a manual boost-controller to remove the stock KLR/CV programming, you'll have a high-RPM drop-off in boost because of the rising exhaust pressure.
So you shim the wastegate to make exhaust-pressure less of a factor:
<img src="http://www.gururacing.net/ImagesMisc/WastegateShimmedManual.gif" alt=" - " />
Then in order to have the same max-boost level as before, you'll need to adjust your manual controller to open earlier at a lower-pressure. However, since the manual controller is a passive device that only responses to pressure-inputs, its outputs will be correlated to boost-pressure coming from the turbo only. Combined with exhaust-pressure, you'll still have the wastegate opening too much in the high-RPMs.
Best solution is a shimmed wastegate (or aftermarket with stiffer spring) and an electronic controller:
<img src="http://www.gururacing.net/ImagesMisc/WastegateShimmedElectronic.gif" alt=" - " />
The electronic controller has active predictive control of the wastegate and can learn the boost-patterns of your turbo and wastegate. It can adjust its control signal to the wastegate to maintain a constant boost-level (this implies a changing control signal which a passive manual controller can't do). For example, the electronic controller can sense RPM and exhaust-pressure (indirectly) by seeing that boost drops off in the upper RPMs. It will compensate by dialing back pressure going to the wastegate at high-RPMs even though boost-pressure is the same. So while a 15psi inlet on a manual-controller will send 10psi to the wastegate at either 3500rpm or 5000rpm, the electronic controller will know to restrict pressure going to the wastegate completely from 5000rpm onwards.
Ok fine! Here you go:
<img src="http://www.gururacing.net/ImagesMisc/WastegateStockManual.gif" alt=" - " />
In the stock configuration, there are actually two forces managing the wastegate and therefore your boost; pressure from the boost-controller and exhaust-pressure (it's actually on the BACK of the valve, I mis-labeled chart). You have to add up the sum of these two forces in order to understand your boost-curve. Even with a manual boost-controller to remove the stock KLR/CV programming, you'll have a high-RPM drop-off in boost because of the rising exhaust pressure.
So you shim the wastegate to make exhaust-pressure less of a factor:
<img src="http://www.gururacing.net/ImagesMisc/WastegateShimmedManual.gif" alt=" - " />
Then in order to have the same max-boost level as before, you'll need to adjust your manual controller to open earlier at a lower-pressure. However, since the manual controller is a passive device that only responses to pressure-inputs, its outputs will be correlated to boost-pressure coming from the turbo only. Combined with exhaust-pressure, you'll still have the wastegate opening too much in the high-RPMs.
Best solution is a shimmed wastegate (or aftermarket with stiffer spring) and an electronic controller:
<img src="http://www.gururacing.net/ImagesMisc/WastegateShimmedElectronic.gif" alt=" - " />
The electronic controller has active predictive control of the wastegate and can learn the boost-patterns of your turbo and wastegate. It can adjust its control signal to the wastegate to maintain a constant boost-level (this implies a changing control signal which a passive manual controller can't do). For example, the electronic controller can sense RPM and exhaust-pressure (indirectly) by seeing that boost drops off in the upper RPMs. It will compensate by dialing back pressure going to the wastegate at high-RPMs even though boost-pressure is the same. So while a 15psi inlet on a manual-controller will send 10psi to the wastegate at either 3500rpm or 5000rpm, the electronic controller will know to restrict pressure going to the wastegate completely from 5000rpm onwards.
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10-17-2002, 05:16 PM
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Ug Danno, you are just amazing........
Magia, the jist of it appears to be that the chips are calibrated not only for the max boost BUT ALSO for the boost curve/characteristics. If you use an LBE to increase boost instead of the provided shim, you may have a boost curve that has a different shape/character than that obtained by shimming. Hence, the chip is no longer optimized and MAY run lean/rich in certain portions of the boost curve that can cause damage to your engine. Thus, you should use your shims....
Danno, feel free to correct my errors if any...I am still merely a turbo-child learning my alphabets....
Magia, the jist of it appears to be that the chips are calibrated not only for the max boost BUT ALSO for the boost curve/characteristics. If you use an LBE to increase boost instead of the provided shim, you may have a boost curve that has a different shape/character than that obtained by shimming. Hence, the chip is no longer optimized and MAY run lean/rich in certain portions of the boost curve that can cause damage to your engine. Thus, you should use your shims....
Danno, feel free to correct my errors if any...I am still merely a turbo-child learning my alphabets....
10-18-2002, 06:12 AM
#9
Race Director
That sounds right on! I'm a big fan of dyno-testing and preventative maintenance. Dyno-time is mightly cost-effective for what you get: peace-of-mind and well-tuned car. It costs much, much less than replacing a headgasket 
.
Actually, you can even skip that dyno-test, we've already done it! There's a dyno-chart of our car in its original condition with Europroducts chips (1/2 way down the FAQ section). On the same chart is a second run with a corrected air-fuel ratio curve.
.Actually, you can even skip that dyno-test, we've already done it! There's a dyno-chart of our car in its original condition with Europroducts chips (1/2 way down the FAQ section). On the same chart is a second run with a corrected air-fuel ratio curve.
