Stupid_fast Posted March 30, 2013 Report Share Posted March 30, 2013 I cant get rid of it... Its an L20b with a 490 lift/ 281 duration cam advanced about 3 deg. Other than cam and valve springs its a stock motor. Under 3500rpm, it will ping at anything but light throttle. Top end runs fine 3500 to 6000 pulls strong. It did it with the weber DGV(less severe) and now on my R1 carb setup. I can make the carb so rich its losing power and barely accelerating, and it still pinging. I can retard the timing back 4-6 degrees and it will not change how it pings. Running a matchbox dizzy and coil. NGK BP5EY. Compression is about 150psi across all four cylinders. I'm running 91 octane. Any ideas? Quote Link to comment
datzenmike Posted March 30, 2013 Report Share Posted March 30, 2013 Maybe not pinging you hear. Quote Link to comment
Stupid_fast Posted March 30, 2013 Author Report Share Posted March 30, 2013 Maybe not pinging you hear. Then what is it? Sounds like pinging. goes away @ 3500 rpm. BRB video. Quote Link to comment
metalmonkey47 Posted March 30, 2013 Report Share Posted March 30, 2013 Sure it's not valve noise? Some aftermarket cams are very noisy. Quote Link to comment
Stupid_fast Posted March 31, 2013 Author Report Share Posted March 31, 2013 It is NOT valve noise. I do have valve tick at idle from the big cam, and I know what it sounds like when its worse. Timing 8 deg @ 1000rpm no vac advance. Went for a quick drive around the block. Ah and an excuse to try out my new fish eye lens for my phone ! VIDEO/sound clip; http://youtu.be/Sx8uzggHSCo Double clutching like I should @ 1:23. If this sound is not pinging, what is it? Quote Link to comment
wayno Posted March 31, 2013 Report Share Posted March 31, 2013 Sometimes an exhaust leak can sound like knocking/pinging, I can't hear anything in that video because I am old and seem to be half deaf, it sounds like you have no suspension, that is all I hear, well that and the carbs, they sort of sound like SUs. Quote Link to comment
Stupid_fast Posted March 31, 2013 Author Report Share Posted March 31, 2013 @ Wayno, There is a ticking/pinking noise when I'm going up those hills or throttling in 3rd along that road ... Then when I open it up higher RPM it goes away. No suspension? Hahah, well I've got 200lb front springs illumina shocks, ect .. its quite stiff but there is definitely a good amount of travel. Also those roads are very bumpy... Even my cressida clunks along. They are quad motorbike / SU-style carbs. Quote Link to comment
datzenmike Posted March 31, 2013 Report Share Posted March 31, 2013 Put air filters on... bet it goes away. I couldn't hear what you hear either... doesn't mean it isn't there, just I'm not hearing it. Quote Link to comment
Stupid_fast Posted March 31, 2013 Author Report Share Posted March 31, 2013 I have an air filter. Its not tappet noise. I can hear it in the vid... Maybe I just have a good headset. Fine, I'll put a camera in the engine bay >: ( Quote Link to comment
racerx Posted March 31, 2013 Report Share Posted March 31, 2013 listened to the video several times did not hear any pinging, did hear a lot of thuds... Quote Link to comment
JAKE719 Posted March 31, 2013 Report Share Posted March 31, 2013 Im not really hearing anything either, but definitely liking the vid! Just curious, what is your gap set at? Chances are it could be pretgnition and not detonation you're hearing. Might try a tighter gap on the plugs, and if nothing with that a step colder plug might get you in the right direction. Quote Link to comment
ssnapz Posted March 31, 2013 Report Share Posted March 31, 2013 I either heard the phone bouncing or something worse then pinging. To me sounds like the ame noise in my motor and discribed the same way. I think mine is a bearind know or piston skirt. Quote Link to comment
Sealik Posted March 31, 2013 Report Share Posted March 31, 2013 Fancy pants.......driving gloves and all.... :D I'd probably buy a wide band and confirm what A/F ratio you are running below 3500 The Innovate I bought helped quite a bit on tuning carbs and or...etc....etc Excellent product for noobs with limited tech 'equipment'..... :D What do the plugs look like after running...?.....check them after just cruising....and then WOTish Cam is in No3 hole? Lash clearance is set at....?..... Timing seems a little low..... Other than my co-pilots.....notice the wide band in vid.....? Quote Link to comment
wayno Posted March 31, 2013 Report Share Posted March 31, 2013 What is your CR? Quote Link to comment
Sealik Posted March 31, 2013 Report Share Posted March 31, 2013 What is your CR? I'm guessing at .............................9.8-10.3 Quote Link to comment
wayno Posted March 31, 2013 Report Share Posted March 31, 2013 I'm guessing at .............................9.8-10.3 Well the crap pump gas in CA will likely not work, even 91, I would try some race fuel(over 100) and see if that makes a difference. Quote Link to comment
Laecaon Posted March 31, 2013 Report Share Posted March 31, 2013 ts an L20b with a 490 lift/ 281 duration cam advanced about 3 deg. Other than cam and valve springs its a stock motor. I'm guessing at .............................9.8-10.3 What is your CR? Quote Link to comment
wayno Posted March 31, 2013 Report Share Posted March 31, 2013 So the CR isn't that high, he is running 91, so what would be your guess. I made a hanggliding trip down to east LA several years ago, I had a stock L20b block with a CC W53 head with big valves that was port matched to the dual SU manifold, basically a 219 head, I put california 89 octane fuel in that tank because the passenger was complaining about having to buy premium, I almost had to empty the tank, it was knocking so bad, I pulled the vacuum advance hose, and retarded the distributor a lot, I got threw that tank and got back home with the engine still intact, and that was when I realized that I could run regular if the timing was set properly. California fuel is crap, they are lucky that an old engine will run on that crap, I suppose that is a good reason to do modern engine swaps down there, because they are made to run on that crap. Quote Link to comment
metalmonkey47 Posted March 31, 2013 Report Share Posted March 31, 2013 I can hear it in the video, but I can honestly say it doesn't sound like pinging from what I hear. My 210 made a similar noise from the mechanical fuel pump before it started to fail. It would get worse at higher RPM's. Just a thought. Can you hear it at idle? Maybe get a cheap stethoscope from the autoparts store and listen to the cylinders?? Quote Link to comment
Stupid_fast Posted March 31, 2013 Author Report Share Posted March 31, 2013 Im not really hearing anything either, but definitely liking the vid! Just curious, what is your gap set at? Chances are it could be pretgnition and not detonation you're hearing. Might try a tighter gap on the plugs, and if nothing with that a step colder plug might get you in the right direction. Gap set at 0.035 I either heard the phone bouncing or something worse then pinging. To me sounds like the ame noise in my motor and discribed the same way. I think mine is a bearind know or piston skirt. Phone is mounted in the seat head rest, so there is no rattle there. ame noise ? Fancy pants.......driving gloves and all.... :D I'd probably buy a wide band and confirm what A/F ratio you are running below 3500 The Innovate I bought helped quite a bit on tuning carbs and or...etc....etc Excellent product for noobs with limited tech 'equipment'..... :D What do the plugs look like after running...?.....check them after just cruising....and then WOTish Cam is in No3 hole? Lash clearance is set at....?..... Timing seems a little low..... Other than my co-pilots.....notice the wide band in vid.....? Yeah I got the driving gloves for christmas ... feels great with the leather wheel. Cam @ no3 hole ? I think so. Its just a tad advanced. last set to 0.08 and 0.010 hot. What is your CR? Not sure honestly... ~160psi cranking comp So the CR isn't that high, he is running 91, so what would be your guess. I made a hanggliding trip down to east LA several years ago, I had a stock L20b block with a CC W53 head with big valves that was port matched to the dual SU manifold, basically a 219 head, I put california 89 octane fuel in that tank because the passenger was complaining about having to buy premium, I almost had to empty the tank, it was knocking so bad, I pulled the vacuum advance hose, and retarded the distributor a lot, I got threw that tank and got back home with the engine still intact, and that was when I realized that I could run regular if the timing was set properly. California fuel is crap, they are lucky that an old engine will run on that crap, I suppose that is a good reason to do modern engine swaps down there, because they are made to run on that crap. Meh cali fuel works.... I can hear it in the video, but I can honestly say it doesn't sound like pinging from what I hear. My 210 made a similar noise from the mechanical fuel pump before it started to fail. It would get worse at higher RPM's. Just a thought. Can you hear it at idle? Maybe get a cheap stethoscope from the autoparts store and listen to the cylinders?? Then what is it? I'm not sure how to describe it. It sounds like a rattle or something but it comes from the engine/ engine bay.. I just went to a meet and had iforgethisscreenname CA18 turbo guy ride in, he said it didnt sound like pinging ... at idle? no. I will get a stethoscope. Its an elec fuel pump now with the r1 setup. I realise doing this on a bridge with speed strips was probably a bad idea now that I think back... lol But you can hear it better in this video. http://www.youtube.com/watch?v=0M8mdAA65FA&feature=youtu.be Dad rode in it... He says it does not sound like pinging ... Quote Link to comment
wayno Posted April 1, 2013 Report Share Posted April 1, 2013 Then I would be back to checking for exhaust leaks around the exhaust manifold and work your way back, another member on here towed their car home because of an exhaust leak. Quote Link to comment
Stupid_fast Posted April 1, 2013 Author Report Share Posted April 1, 2013 Alright ... If it were in fact pinging, advancing the timing would make it much louder, correct? I may try to adv the timing to like 15 or 18 deg and see what it sounds like. My mechanic friend maybe be able to take a ride in it sometime this week ... thanks for the info everyone. Quote Link to comment
racerx Posted April 2, 2013 Report Share Posted April 2, 2013 yes pinging should inrease increase if timing is advance, cheap gas also causes engines to ping or using too low of an octane when what is needed is like 91 or so..seems like your trying to isolate the issue. Quote Link to comment
ssnapz Posted April 2, 2013 Report Share Posted April 2, 2013 If you can tell its not pinging you can also tell if its backfiring in the exhaust. That sounds internal to me. Quote Link to comment
Stupid_fast Posted April 8, 2013 Author Report Share Posted April 8, 2013 yes pinging should inrease increase if timing is advance, cheap gas also causes engines to ping or using too low of an octane when what is needed is like 91 or so..seems like your trying to isolate the issue. Put it at 12deg, no change. I'm running 91, never ran anything lower. If you can tell its not pinging you can also tell if its backfiring in the exhaust. That sounds internal to me. Maybe its un burned gas under load in the low end ? I know its strange, but when I increased the jets with my old carb it made the noise slightly worse. With this carb, when I put rich jets in it just ran bad, no change in noise. It only happens in torque, under load. its a consistent noise. I really just don't know what to try next. Probably going to end up taking it to a shop Quote Link to comment
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