I might have to take my engine to a Pro. [Archive]

View Full Version : I might have to take my engine to a Pro.

GRNOVA

11-09-2009, 03:31 PM

I have a 250 power charger on my 383 sbc, msd 6btm, and a 850 demon running 7.5 psi w/a-1000 intank pump. Timing locked at 34* run through 3" exhaust. I am stumped dont know what to try next.https://static1.pt-content.com/images/noimg.gif
Car is having major engine problems,backfiring through the pop off valve, fouled plugs,and smells like gas in oil.

gearheads78

11-09-2009, 03:53 PM

Has this car been running OK or first time to get it running?

What part number regulator are you running? What size fuel line and return line?

6'9"Witha69

11-09-2009, 03:54 PM

And you are sure the dist isn't 180* off?

1969CamaroRS

11-09-2009, 04:02 PM

And you are sure the dist isn't 180* off?

x2, don't ask how I know :idea:

Simbad68

11-09-2009, 04:50 PM

x2, don't ask how I know :idea:

Been there, done that!!

6'9"Witha69

11-09-2009, 05:28 PM

Me too, lost an eyebrow and some of my hairline until it grew back!

GRNOVA

11-09-2009, 06:19 PM

Thanks guys for the suggestions. I checked the dis. it is fine.

I am running an aromotive 12304 -10 fuel feed, and -8 return line

And this is not the first start up. I have had the car out plenty of times since it was dynoed in Dec 08. I has been running increasingly bad since it was put back into the car.

I kind of feel like I am giving up by taking it somewhere,but I am as far as my knowledge will take me.

I just got back form dropping the car off at HighSpeed Performance. (http://highspeedperf.com)

Mike Lopez the owner is going to run through and find out what is wrong.

I hope it is not to costly:fingersx:

GRNOVA

11-09-2009, 06:23 PM

Here is the dyno sheet from Nov 08
https://static1.pt-content.com/images/noimg.gif

gearheads78

11-09-2009, 07:45 PM

I can't find that part number. Are you sure its not this one? 13204

I found out the hard way that pump and regulator combo needs -10 feed and return in a carbed application. I had a similar problem you are describing and started rooting around on the FI boards and talked to Kevin at CSU. I followed the advice and changed to -10 return and cured it. Basicly with -8 line pressure backs up and the only place to go is the needle and seat in the carb.

https://static1.pt-content.com/images/noimg.gif

GRNOVA

11-10-2009, 06:15 AM

I'm sorry it is #13204 I had the numbers wrong. I will relay this information when he calls me and tells me what he finds. I know that when I dropped it of he was not liking the Demon carb!

John Wright

11-10-2009, 06:39 AM

I know that when I dropped it of he was not liking the Demon carb!
LOL...I have had that same feeling when I owned one of those. Hopefully they have improved in the QC department over the last few years. Ask him to take the bowls off and check for left over mfg'ing debris...(little aluminum shavings that can get wedged between the needle and seat)

GRNOVA

11-14-2009, 07:01 AM

Got the car back last night! The car runs better than it ever has. He said that this was the first Demon that he liked. We went with 2 size hotter plugs adj carb by leaning it out a little changed jet sizes and pulled 397 RWH on the chassis dyno and 12lbs of boost:) I am getting ready to take it out and DRIVE!

94SNGLTURBO

12-08-2009, 09:13 AM

good to hear everything worked out...

monza

12-08-2009, 09:26 AM

GRNOVA

12-08-2009, 12:10 PM

:hmm::confused::dunno:

Glad it worked out but, :enguard: that fricken beastly looking motor is only putting out 397 RWH... MORE BOOST!

steelcity6

12-08-2009, 12:16 PM

WOW .. I had the exact same problem with my demon...thought it was a fluke. sent it back went back to a 4150 holley