COP's, Resistors & VBoost opening RPM

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dannymax

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There seems to be some pretty good evidence that running COP's without resistors on the earlier model VMax's can result in a change in the boost opening rpm from 6K ± to around 7500.

I and a couple others have noticed this....anyone else?
 
This is strictly from memory....but isnt stock V-boost start to open at 6000.....and them fully open at 7000 -7500?
 
One of the things that I like about the Ignitec, is that the Vboost goes from closed to fully opened in 1/2 a second. THATS a rush.

Hmmm, didnt' know that. I wonder if there's a vboost controller mod to do same thing.
 
One of the things that I like about the Ignitec, is that the Vboost goes from closed to fully opened in 1/2 a second. THATS a rush.

Can't wait to install my ignitec I like a good rush !! Right now I don't feel boost at all I may go back to stock coil so I can use my sasy I really liked having that with my dragstar exhaust just a push of a button and instant vboost especially at idle BIG thumping CAM STYLE !!
 
This is strictly from memory....but isnt stock V-boost start to open at 6000.....and them fully open at 7000 -7500?

Not sure about the full open rpm but starting at 6K is right.

I didn't know about that snap open function with the Ignitek either....that's got some real appeal!! :punk:
 
Hmmm, didnt' know that. I wonder if there's a vboost controller mod to do same thing.

Here are Pics from my computer from the ignitec file.

On this screen, the KPA range on the side doesnt matter, the Vboost is RPM driven, and because of that you get just as much Vboost at about 1/3 to half throttle. It makes it very fun to drive around town.
 

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Hey Eric care to post that on the Ignitech thread, the whole setup to have VBoost butterflies running from the ignition rather than the vboost controller? thank you
 
I installed COPs during winter, and I don't notice vboost same like earlier..? I've seen oil light, so I think it works, but might be that it comes in later than before. I checked the vboost cable, it should be OK. I have Ignitech too, that vboost control would be awesome but it may need too much of me to get that working.. :(
 
I attached a picture showing how I have been setting VBoost opening up in units purchased from me.

I put arrows from RPM/Percentage blocks to the corresponding yellow dot on the graph that block controls. Block #1 controls yellow dot #1, Block #2 controls yellow dot #2 so on.

There are 10 blocks to the right of RPM on left side of screen. Each one of these blocks can be set at any RPM, in 100 RPM increments. RPM settings must increase left to right.

Below the RPM row, there is a row Percentage, This row sets the amount of rotation of the servo motor. It will somewhat closely match the percentage of VBoost butterfly opening. Each block in the Percentage row is tied to the RPM setting above it. The percentage values can be anywhere between 0 and 100. They do not have to increase left to right like the RPM blocks.
On the graph, the numbers bottom to top on left side represent percentage of opening. (0%, 20%, 40%, 60&, 80%, 100%,120%)

In 1st picture, VBoost is set to go to 11% opening at 4900 rpm, then 22% at 5100, 42% at 5,500, 60% at 5,600, then 100% the rest of the way.

In the second picture, I set it up for DEMO purpose only, to show versatility of Ignitech TCI. VBoost is set to go to 34% at 4600, 66% at 5,200, 100% at 5,800 to 7,000, then decrease VBoost to 67% at 7,300, 50% at 7,500 the rest of the way.

This chart can be dialed in to whatever you want. It requires a computer connection via a usb/com cable to reset, it can not be done like Dyna with dip switches.

Gary





 
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Would the TBoost mod help open them at a lower RPM on an early model with COP's? I am building an 85 and just installed a set of COPS without resistors.... Should I add resistors to keep the vboost opening normally
 
Would the TBoost mod help open them at a lower RPM on an early model with COP's? I am building an 85 and just installed a set of COPS without resistors.... Should I add resistors to keep the vboost opening normally

The least of your concerns is the Vboost. If you are running the stock ignition unit you are prone to have it burn due increase in current to COPS.
 
Seems like alot of guys are running the COPs on here with no problems...
 
There seems to be some pretty good evidence that running COP's without resistors on the earlier model VMax's can result in a change in the boost opening rpm from 6K ± to around 7500.

I and a couple others have noticed this....anyone else?

Not sure about the range, but I don't feel the vboost of my 89 at 6k the same way than before. I just never thought it was related to the COPs but something else. I have been look for the reason for quite sometimes. :bang head:
 
Not sure about the range, but I don't feel the vboost of my 89 at 6k the same way than before. I just never thought it was related to the COPs but something else. I have been look for the reason for quite sometimes. :bang head:

Do you have resistors inline with your COP's? Just wondering how to set mine up
 
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