Failsafe then and does the job. Great. Thanks for that, :) appreciated

If you can find a spring maker, they can make anything you want - after all , that is where springs come from. I had a bunch of ranges made up, for about $20 each. Working off my base unit of 0.8 bar, I simply had him give me a range of softer springs to play with.
I have my 0.7 bar out at the moment, so can give you some specs to work off.
When compressed in the can my best estimate is the compression length is 73 mm. Placing them on bathroom scales and compressing to 73 mm (with my w/shop press) I measure 85lb. You need to work in %ages. So if you give a spring maker a 0.7 bar spring, and want a 0.6 bar, you want a spring about 12% softer.
The calculations they do off your base spring will get them there near first time.
Unfortunately my spring maker recently passed on, but they are around. The trick is probably to find a small business dealing in this , rather than a big factory.
Your 0.6 bar spring should compress to around 75lb at 73 mm.
Alan

I bought a Tial to get acces to a .7 bar spring for my last turbo.

Alan

Priceless information THANKS !!!!!!

Cole

Well, just finished the last piece I needed to complete the ECB and wastegate
package;

Not Exactly Pretty;

http://forums.pelicanparts.com/uploa...1290968620.jpg


Which is the .43 Spring?

http://forums.pelicanparts.com/uploa...1290968691.jpg


Alright (1) 930 .43bar Wastegate

http://forums.pelicanparts.com/uploa...1290968799.jpg


Cole

Cole where do you get a 2 bar map sensor and what is a spdt relay and how do you implement this with the solenoid. Inquiring minds would like to know Thanks Sam

I wanted to add a couple comments regarding all this information about lower boost springs and adjustable wastegates.

The 75-77 930's have .7 bar springs, 78-89 .8 bar boost springs, and 964 S .9 bar boost springs. These are the stock springs that these 930's came with from the factory, They are considered, by the factory, as designated safe boost levels for each of these model years.

I have an 80 930 ROW car and it came from the factory rated at 300 HP. With bolt on modifications only and a little more boost it is relativly easy to gain 25- 75 HP and still run safely. If And Only If, the following modifications are made first. Larger intercooler, free flow exhaust (preferably headers), strict fuel control, strict timing control, and good boost control. These are ( The Holey Grail of 930 Modifications) Never exceed factory boost levels without these modifications.

Now, there is no reason to run a boost spring with less boost rating than the factory spring as well as no reason to run a boost spring with more boost rating for your model. With that said, we are back to the point of this thread, adjustable boost.

Do not be misled by my using a .43 bar boost spring as it does no good to have it unless you are looking at it as insurance. I am running Water/ Methanol Injection which allows me to run much higher boost levels safely. If that WMI should malfunction at a high boost level it will be real ugly. I have a failsafe system with the WMI system that monitors the WMI functions and will produce a 12vdc fault output if any of the functions fail. If I should have a WMI system failure the fault output will open the boost solenoid which will dump the boost back to spring pressuer, .43 bar and retard the ignition back to 16o total advance to create a safe run condition. This is the only reason I'm using the .43 bar spring.

You should run the exact boost spring designated for your model and then add boost control to adjust for higher boost, but only do this after you have complied with (The Holey Grail of 930 Modifications) above. I would recommend controlling boost with an Electronic Boost Controller because if it fails it will always fail back to stock boost spring pressure and will lessen spool lag.

Cole

Sam:


I am assuming you are asking about the fail safe for the WMI.

I purchased a Snow Performance SafeInjection™ module to go with the WMI. It is what monitors the WMI and produces the 12 vdc fault out put. Not cheap but
well worth the cost to save your motor. It is interfaced with the controller and uses the existing MAP sensor in the control to monitor the boost pressure. I wired the SafeInjection™ fault output to a Bosch SPDT ( single pole/double throw relay)
I then wired the EBC power wire to the nc (normally closed) relay contact and the
MSD timing retard line to the no (normally open) relay contact. If the SafeInjection™ sees a fault it powers the relay coil, opening the (NC) contact which kills power to the EBC and opens the boost line to exhaust and closes the
(NO) contacts and sends 12vdc to the MSD to retard timing.




http://forums.pelicanparts.com/uploa...1291143517.jpg


Internal Workings of Bosch relay:

The following diagram shows what those external terminals are connected to on the inside of the relay. When there is no difference of potential (voltage) across terminals 85 and 86 (the coil), the relay's movable contact (connected to terminal 30) is held, by spring tension, against the electrical contact which is connected to terminal 87a (the normally closed contact). In other words, when no voltage is applied the the relay coil, terminal 87a is connected to terminal 30. When 12 volts is applied to the relay coil (terminals 85 and 86), the movable contact (connected to terminal 30) is pulled down/in by the electromagnet (coil) so that it physically contacts the electrical contact which is connected to terminal 87. Again, in other words, if battery voltage is applied to the relay coil (terminals 85 and 86) terminal 30 will be connected to terminal 87. The red dashed line shows the path in which electrical current flows from/through terminal 30 to the contact of terminal 87a when the relay coil is NOT energized.

Hope that helps. You can always call me at 260-570-6914

Cole

Cole what if there's a failure of the old man driving way too fast??? Got a parachute wired into anything? :-))

Cougar Bait :

Where the hell have you been, I probably don't want to know.

One thing for sure, I didn't consider a failsafe for myself. Just know, I'll make it as spectacular a crash as I can while knowing all the time that it's a lot better than croaking in the home while tied in a chair s------- myself.


Cole

Cole just landed in reno been in NH with my kids for a week
I'll call u soon to catch up

Cole, one last question. :)

The EBC prevents the wastegate from early leakage. Does that result in noticeable earlier boost?

A larger IC cools the air more and makes it more dense. Does that mean a gain in power or only that the engine can run at a higher boost if desired because it's less susceptible to damage?

So, if I only installed an EBC as you've described and a larger IC, nothing else, what gains would I get and would they be noticeable?

A larger IC can make 30 more HP at the same boost. It also allows you to run more boost with out issue. Double whammy!

EBC can make for a little more HP at first boost. No more at full boost. Nor should boost start any sooner.

Stu:

I personally believe the larger IC is the first and the most important mod you can do for these cars. Defiantly not the least expensive mod, but by far the most beneficial. The larger IC adds significant cooling of the charge air and cylinders which pays you back threefold. Allows more charge air into the cylinder, deters detonation through cooling, and creates more HP. Can't beat that bang for the buck.

I'm assuming when you change IC's you will go with a long neck cooler and eliminated the original recirculation assembly. There are advantages to be gained with this change as it cuts down the volume of intake area that has to be recharged before boost develops again after throttle lift.

The EBC, I originally hesitated to invest in an EBC because I didn't necessarily see any big advantage to using one. But when you start looking closely at wastegate operation you realize it is like blowing up a tire with a hole in it, it bleeds off air as it is being filled. The wastegate bleeds off air as it opens untill the air in the diaphram is sufficient ot overcome the spring pressure and the valve lifts completely. The time it takes to open the valve is longer because of having to overcome the bleed pressure as well as the spring pressure. This process actually delays the time it takes to reach full boost and open the wastegate. With an EBC the valve is held shut tightly by the pressure in the top wastegate chamber pushing against the top of the diaphram until full boost is reached. When full boost is reached the EBC drops voltage to the boost solenoid and the pressure on the top of the wastegate chamber is immediately exhausted and the valve opens instantly. The EBC gives you very precise control of boost and always go to an exhaust condition if there is a controller fault.

Your choice of the EBC and larger IC as your first mods is an excellent one. It's the right choice and you will be duely rewarded by the wide grin on your face after the first ride.



Cole

I have a Greddy EBC also, and mine allows me to set the exhaust characteristics at full boost - ie how fast you want the onset of the dump. You can have a slow or fast response, and control some boost characteristics when things are not working to exact plan.
Alan

Exactly what I had hoped you'd say. Thanks

If I do then go for a K27 later I have the essentials in place already. TBH I wanted to make as few changes from stock as possible but I may have to go long-neck if that's works out cheaper or bestter in the long-run. If I don't, how much am I losing out?

Stu:

Changing to a long neck cooler can be done easily and you just bag up all the
stock parts you take off. If you ever decide to go back to stock you simply
drag out the bag of stock parts and reverse the process. You don't have to cut up or destroy any of the original parts to make this change. And the long neck is the only way to go. It will improve spool time and response.

Something I'd like to suggest; Would you mind changing your forum signature, the bottom of your form page, to list what your car is and any mods you have. ( If you look at the bottom of my page you can see everything I have done) This gives others valuable information when trying to help you with questions you might have. It would also be helpful to know how you use your car and what you are looking to accomplish, quick light to light, track work, long distance driving, etc.

Cole

OK, let's test what I've done.

Stu:

Awsome buddy !!! That will help everyone, Thank You !!!!


The great adventure you have before you is a labor of love. Sometimes it's like raising a child, you always love them but sometimes you won't like what they do.


Cole

And sometimes you just plain won't like them!! Fortunately mine are both living their own lives so the only baby sucking me dry is this one! :)

I've had countless narrow-bodied impact-bumpers, several 964s and 928s, never ever considered a 930, how did I miss this one for all those years?

I just love the car, I love the way it's so planted on the road, it's technical (relative) simplicity, it's mechanical rawness, like a Ducatti Monster, all exposed guts and bones (well, underneath anyway). :D

If I had the guts and the cash, I'd do all the performance upgrades, strip it out, lighten it etc and I may well do some of that temporarily as the restoration progresses and have some fun but I always want to be able to return it to stock easily. You never know when you have to sell.

I'm going to enjoy getting my hands dirty over the next year or so attempting to do stuff I've never done before. I have my trusty Haynes and 101 and cannell manuals to guide me through plus this and other forums to get advice

All I need now is the British weather to cooperate! :cool: