jason's education thread

[good2win22]

Here ya' go Jason...and I'm likely putting one in my car.

http://www.bmotorsports.com/shop/product_info.php/cPath/103_107/products_id/357

Thanks for the link Brad

I worked on my A/C yesterday evening. 

That's just because some moocher borrowed and kept your gauges for way too long. I'm glad you got them back.

P.S. I really appreciate the loan. Thanks for your generosity.

No worries Rich.  Your welcome to whatever I have that you need.

Jason, what kinda heads did your old car have?

Those heads were untouched stockers with comp 981 springs installed.  Also had the TA performance race headers with the band clamps.

I guess I need to start reading to see how many time steve has said " I wish William would just sell his car"

You won't get much love on this board William. LOL!  I bet we have all felt the wrath of Steve at one time or another but he always seems to calm a bit and still help us nitwits. Maybe he's a gluten for punishment or maybe, just maybe he really does like us

[Steve Wood]

I guess I need to start reading to see how many time steve has said " I wish William would just sell his car"

I have only thought it....lol

What I have said is I wish you would read the instructions!!

[TexasT]

I guess I need to start reading to see how many time steve has said " I wish William would just sell his car"

If you sold it where would we get fodder for this and other boards?

I think you were doing fine. One change at a time and then run it to see what it does. Lots of runs makes for a well tuned ride.

[good2win22]

New question fellas....  Who has run 1.65 ratio rockers on a completely stock head and cam? Problems? Gains? Losses?  Valve cover issues?

[Scoobum]

New question fellas....  Who has run 1.65 ratio rockers on a completely stock head and cam? Problems? Gains? Losses?  Valve cover issues?

If you're gonna change the ratio...then you could run into coil bind. I had Joe set my heads up for the stock 1.55 rockers.

[Charlief1]

New question fellas....  Who has run 1.65 ratio rockers on a completely stock head and cam? Problems? Gains? Losses?  Valve cover issues?

The rockers have to be clearanced for the rockers and besides the coil bind issue you may need to cut the guides down since they only have enough room for about a .460 lift.

[good2win22]

New question fellas....  Who has run 1.65 ratio rockers on a completely stock head and cam? Problems? Gains? Losses?  Valve cover issues?

The rockers have to be clearanced for the rockers and besides the coil bind issue you may need to cut the guides down since they only have enough room for about a .460 lift.

I gotta take some measurements and do some math.  I planned on the valve covers having clearance issues but it's been a while since i put these rockers on my barn heads to see if there were any issues with clearance with the pedestals. 

[good2win22]

Next question....


Is there logic in the ECM to turn off the radiator cooling fan when temps are above the preset turn on limit but the car is driving say in 4th with the TC locked? Would having A/C on and pressure above 150 on the high side over ride this feature if it does exist?

[Steve Wood]

not to my knowlege.

The AC pressure and high temp turn ons don't go thru the ecm so they counteract anything else.

[good2win22]

Thanks Steve.  I was watching the powerlogger screen and didn't see the fan on box checked but could tell by the load on the voltmeter that the fan was on.  Was curious if the fan being on would create a differential pressure and "back up" the air flow.  I would assume that the incoming airflow  would just push the fan to a higher speed than what the motor was turning it at.  Probably a stupid thought but sometimes I think about shit like that

[Steve Wood]

Jason, I am too lazy to go look at the code, but, I think the factory chip was programmed to turn the fan on around 200 degs.  In many cases, this meant that the fan did not run when the car was going down the road at speed because the system was adequate to keep the car below the turn on temperature when moving rapidly.

Now, when we reprogram the fan to come on at 168 degs, or whatever number the programmer chooses, the system, in the summer, cannot cool the car down to this number so it runs all the time.  The fan then becomes a resistance to air flow as you suspect.  It may speed up some, but I would bet that it still blocks air flow somewhat.

And, whatever the case may be, the AC trumps all because it is a mechanical switch programmed to make the circuit when the pressure reaches a certain level.   

[good2win22]

Next question...
 
Does someone have a link or source that explains fuel pressure vs fuel volume vs injector duty cycle?

[Steve Wood]

volume changes by the square root of the new pressure divided by the old fuel pressure.  You have to be careful about not mixing cc/min and lbs/hour...Lotsa formulas out there\

http://www.witchhunter.com/injectorcalc1.php


I use 0.65 normally for bfsc

[good2win22]

Thanks for the link Steve.  Been reading their explanation links as well.  Trying to learn so I can calculate what the demand would be to require an internal  dual pump or perhaps an external pump that can move the volume or if it's even needed at all...

[Steve Wood]

The answer if probably when you hit the nines when spraying alky.

Dual pumps are Rube Goldberg.  There are a number of higher output single pumps available altho some may require a larger return line to adequately control pressure at idle.  A larger supply line will always help get the volume capability of the pump to the front of the car.

External pumps are rarely required on a car that can be street driven.

In the end, as long as fuel pressure at the rail reads what it should for the boost being run, the pump is large enough