Eaton SG 1989 w/low fuel pressure
11-13-2006, 10:12 AM
#16
Tony, i have a question for you, im running 6psi, i have a v2 vortech supercharger stock exauste with the ex of rbm my idel fuel presure is 30lb and im running 30lb injectors in an 87s4 auto. my question is that my boost does not build like what your showing, if i floor it, it build gradaully and slowly.I have the lc-1 but its not working and i have to send it back so in the mean time i have a narrow band hooked up and it shows that im rich in wot but does not max out it the richment reading (maybe 3 more leds to go). is this the norm? and go i need to increase fuel presure Im also running a 12:1 fmu. thks
11-13-2006, 11:36 AM
#17
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Originally Posted by S4-on-your-back-door
Tony, i have a question for you, im running 6psi, i have a v2 vortech supercharger stock exauste with the ex of rbm my idel fuel presure is 30lb and im running 30lb injectors in an 87s4 auto. my question is that my boost does not build like what your showing, if i floor it, it build gradaully and slowly.I have the lc-1 but its not working and i have to send it back so in the mean time i have a narrow band hooked up and it shows that im rich in wot but does not max out it the richment reading (maybe 3 more leds to go). is this the norm? and go i need to increase fuel presure Im also running a 12:1 fmu. thks
This difference in boost curve is why positive displacement superchargers are so much better than turbo's.
11-13-2006, 11:43 AM
#18
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Bill, the car would be jerking at low speed like a bull. Also at complete stops the RMP would drop from 750 rpm to 450 and back to 750 rpm. The car cranks on the first turn but would crank slow like its barely making it. Also low low low fuel pressure levels :-).
11-13-2006, 11:48 AM
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Originally Posted by Giovanni
Bill, the car would be jerking at low speed like a bull. Also at complete stops the RMP would drop from 750 rpm to 450 and back to 750 rpm. The car cranks on the first turn but would crank slow like its barely making it. Also low low low fuel pressure levels :-).
11-13-2006, 12:52 PM
#21
Three Wheelin'
The car should idle and run at normal speeds w/o boost perfectly normally. 30# of fuel pressure is more than enough to cruise. Slow cranking is another problem entirely.
11-13-2006, 01:56 PM
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Originally Posted by Bill Ball
Is the cranking slow only once the car warms up? You may know where I'm going with this.
11-13-2006, 01:59 PM
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Originally Posted by BrianG
Your boost build is normal for the type of pump. Tony's using a positive displacement type and yours is a centrifugal type (much like that used on turbo-chargers).
This difference in boost curve is why positive displacement superchargers are so much better than turbo's.
This difference in boost curve is why positive displacement superchargers are so much better than turbo's.
11-13-2006, 02:31 PM
#28
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Originally Posted by bd0nalds0n
I thought TBF was exclusive to autos...?
11-13-2006, 03:51 PM
#29
Three Wheelin'
If it's bucking and humping and won't crank, and it's due to the crank walking, FUBAR is past, not future tense.
Personally, and this is just opinion with no stats to back it up, I think TBF is exclusive to the autos, but I would be interested in hearing if there are any examples of TBF in a 5-sp. I am under the impression that it has something to do with the later model automatic torque tubes, because the earlier model autos don't have the same problem.
Personally, and this is just opinion with no stats to back it up, I think TBF is exclusive to the autos, but I would be interested in hearing if there are any examples of TBF in a 5-sp. I am under the impression that it has something to do with the later model automatic torque tubes, because the earlier model autos don't have the same problem.
11-13-2006, 04:27 PM
#30
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Actually I misred Gio's sig in my haste. His car being a 5-speed makes TBF far less likely, but it is possible, having to do with clutch pressure on the flywheel and crank rather than a maladjusted TT clamp.
We need a precise description of the symptoms and under what conditions they occur. The slow engine cranking when hot can be other things than TBF (e.g., could be the starter). It would be worthwhile to see if the force required to turn the crank is higher than when cold.
When does the bucking occur? Just hot? All RPMs? Any other symptroms that may provide more clues?
We need a precise description of the symptoms and under what conditions they occur. The slow engine cranking when hot can be other things than TBF (e.g., could be the starter). It would be worthwhile to see if the force required to turn the crank is higher than when cold.
When does the bucking occur? Just hot? All RPMs? Any other symptroms that may provide more clues?