Sputtering buggy --- help

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Stone500
Posts: 7
Joined: Mon Jun 18, 2007 8:00 pm

Sputtering buggy --- help

Post by Stone500 »

Heya...this one's for the engine guru's out there. My little stock 1607 with pict 30 is having a little trouble keeping power when taking corners, it seems to sputter and act like the timing is off when in the low RPM's, mostly coming in the 1,000 - 2500 RPM range, no tach, just guessing by ear. I really have to keep the RPM's up to avoid this -- seems odd. I recently had the valves reset and installed a new 009 Dist paired with a blue coil and the timing was set correctly....also made sure the gas jet was spraying directly into the throttle body and not bouncing off the butterfly. Any suggestions or recommendations? Do I need to install larger jets? I don't have the $$ right now to go to the dual Kadrons but that is my next upgrade, along with a manx sidewinder exhaust system
CairoManx
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Joined: Sat Mar 26, 2011 5:00 am

Post by CairoManx »

[QUOTE="Stone500"] it seems to sputter and act like the timing is off when in the low RPM's, mostly coming in the 1,000 - 2500 RPM range, no tach, just guessing by ear. I really have to keep the RPM's up to avoid this -- seems odd. I recently had the valves reset and installed a new 009 Dist I don't have the $$ right now to go to the dual Kadrons but that is my next upgrade, along with a manx sidewinder exhaust system[/QUOTE] Sounds like the normal 009 flat spot. I have a 1600 DP with a 34PICT. It had a 009 and would bog down as soon as I touched the gas. I got the SVDA a couple years ago. It totally fixed the flat spot. http://www.aircooled.net/gnrlsite/resource/articles/distributor.htm http://www2.cip1.com/ProductDetails.asp?ProductCode=VWC-043-905-205
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rzeller
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Location: Wilmington, NC

Post by rzeller »

[QUOTE="CairoManx"]Sounds like the normal 009 flat spot. [/QUOTE] Nelson, You beat me to the answer :D Stone500, I had the same problem (1600 DP) with my engine right at 1800 rpm. A friend (Mike - Mightymanx) sold me a pict 34 carb with larger jets that helped a lot to reduce the effect. I've since replaced the carb with dual Webers (completely eliminated the problem - expensive solution) and don't need the carb any more. You are welcome to carb if you want it. I'm in Wilmington (2 hours from you). If you want to come down and pick the carb up let me know. Bud
Bud Zeller
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90volts
Posts: 468
Joined: Mon Mar 14, 2005 9:00 pm

Post by 90volts »

what is this flat spot i always hear about? i was thinking of checking for it on snopes.com :D i have a 34pict with the 009 and have never felt anything like a flat spot. i cannot get it to idle below 1000rpm but thats not exactly the same thing and hasn't been an issue cause i just keep the idle up around 1000. been anywhere that it may have gotten some dust or dirt into it? maybe just need a cleaning. poor man's tune up or pull it off and clean it all out.maybe there's a spec of dust iin the idle jet? also, sure the filter isn't getting clogged?
Lee
Posts: 246
Joined: Tue Mar 15, 2005 9:00 pm

Post by Lee »

"what is this flat spot i always hear about?" Do this: Get the engine fully warmed up and find a large, empty parking lot or suitable section of street. Just make sure it's somewhat level. Now put the car in first gear and let the clutch out. Idle along in first gear for a while with your foot completely off the gas pedal, clutch, and brake. Now quickly push the gas to the floor. Do not touch the clutch or feather the gas, just go from being off the pedal completely to on it full in one quick, smooth move. Be careful not to over-rev the engine, we are only interested in the idle to WOT transition. If the engine smoothly increases RPMs without any hiccup, you have one of the very few 009 / 34PICT combinations that seems to work. Most of them will have a hesitation that can sometimes be more heard than felt: Wa---WAAAAAAAAAA. An engine in good tune with an SVDA distributor will pass the above test every time. If it doesn't, adjust the accelerator pump. Which direction (more or less fuel) will take some experimentation.
Lee
Posts: 246
Joined: Tue Mar 15, 2005 9:00 pm

Post by Lee »

"i cannot get it to idle below 1000rpm" That's not a problem. I keep mine just above 1,000 RPM because it helps keep the oil pressure up at idle and it also helps the engine cool itself.
CairoManx
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Joined: Sat Mar 26, 2011 5:00 am

Post by CairoManx »

Stone, The SVDA won't work with your 30 PICT. With the 30 PICT, you need to put the stock centrifugal advance distributor back on. If you change to a 34 PICT as well as an SVDA, you'll get smooth acceleration as well as 10-15mph higher top speed. Used 34 PICT cabs go for $15 and up on Samba.
Lee
Posts: 246
Joined: Tue Mar 15, 2005 9:00 pm

Post by Lee »

"The SVDA won't work with your 30 PICT" That actually depends on which 30PICT it is. The SVDA with the large vacuum can does work with the 30PICT-3 as well as the 30/31 carbs, but it will not work with the 30PICT-1 or the 30PICT-2. More info: http://aircooled.net/new-bin/viewproduc ... 01&cartid=
90volts
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Joined: Mon Mar 14, 2005 9:00 pm

Post by 90volts »

lots of info. thanks, i will try that out.
fubar
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Joined: Mon Apr 11, 2005 8:00 pm

Post by fubar »

Have you checked the float level?
Stone500
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Joined: Mon Jun 18, 2007 8:00 pm

Thanks Buggy Dudes

Post by Stone500 »

Thanks for all the great info.....it did seem to run better with the old carb but I thought it may just be tuning or jetting.....just goes to show hype around certain engine parts is sometimes just hype...glad I have you guys for support. Going to try the dual carb approach or go back to a pict 34 with the SVDA as suggested....like the idea of an extra 10-15 MPH over the 85 I've already topped out at....although she gets really squirly on the highway.... Going to get it lowered a little, add roll bars and get better brakes so I can go quicker and safer.
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