Engine pinging? what to do??

-
BARRACUDA340S

BARRACUDA340S

Well-Known Member
Joined
May 13, 2004
Messages
1,010
Reaction score
1
Location
MT PLEASANT IOWA
I have a 416 stroker which is supposed to have 11.6 comp. I can not keep the thing from pinging. It never did it with the auto and 4000 stall. Now that I have the 4 speed it wants to ping right when I lay into it. I recurved the MSD dist way back and even have a retard knob in the car so I can dial it WAYYY back and nothing helps. I run 5 to 7 gallons of 110 with 5 to 7 gallons of 92 mix. That should do it with my compression.

Other than trying straight race gas what can my problem be?

To much compression for my mildly ported E heads?

Cam is 262@50 and 613 lift, I'm running a Air gap dual plane?

Will better flowing heads make any difference?

I have plenty of fuel feeding the motor.

I run the same plug Scotty runs NGK R5671-8

I need some idea's, if I have to run straight race fuel in this thing then I might as well get some Indy D1's and make the power straight race fuel requires.

What do you guy's think?
 
If the world was the way i think,you should just send me the motor and ill fix it some how and run if for a few years :D just to break it in properly :thumrigh:
as for as the ping sound where does it sound like its coming from?How loud?And i think that some better flowing heads will help u get some more power out of her :scratch: BUT WHAT DO I KNOW I HAV A LITTLE 318 :cheers:
 
Hey Brett,

You shouldn't be pinging running E heads with that comp and gas mixture. How is your crank to cam timing?

Jack
 
Brett how many miles are on your motor now? Do you do alot of low rpm cruising ? May be carbon building up on the pistons and combustion chambers raising compression. You work at a GM dealer, pick up a can of top engine clean. :thumrigh:
 
The cam is advanced 4 degree's and the cranking compression is in line.

No, I don't do any low rpm cruising. There is alway's one of my feet on the floor board! :lol: This motor may have 500 miles on it or so. My plugs look good so I doubt it is carbon.

If I get to the point of running straight race fuel then I'm gonna make her a race motor. I think I might just buy Indy D1's and push about 600 Hp, then I wouldn't feel so bad running $3.50 race fuel. I kept the motor sort of de tuned so I could run pump gas. Seems as if that ain't gonna work. A 600+ HP small block would be cool though :thumrigh:
 
I agree Brett, Let it do what it was ment to do. Run the indy's and be done with it. I will just have to stay away from that small block :shock:
 
If by stating E heads, you mean Eddy's, then you don't have a head problem you have a compression issue. If your at sea level about 10 to 1 or 10.5 to one is all your going to be able to get away with on pump gas and aluminum heads, 9 to one on iron heads. If you go to indys, your going to get the same results unless you go way up on your chamber size. You need to pull the pistons our and take some metal off if you want to run pump gas on the street. If you don't, and want to run race gas, then let the good times roll. We are at 4500 feet, and I have done a lot of playing around with compression and aluminum heads, the most we can get away with is 11.5 to one with a big cam. That is real border line, 11 to one is the best bet. But our air is very seldom below 6000ft in the summer.

Earl
 
I talked to the engine builder and basically I have to much cylinder pressure and that's why the 4 speed is causing me fits. I don't mind running some race fuel with 92 octane but if I gotta run straight race fuel I want the horsepower to go with it. We are going to go with the Indy heads and comp cams will take care of me on the cam. If we do everything right I should be able to mix the fuel and make horsepower. Doug thinks 650 to 700 HP is attainable with straight race fuel and 600 to 650 with a mix. They just didn't get the combo set up for a 4 speed car cause I had an auto and stall when they did the motor.
 
11.6:1 is really stiff even for that 262@50 cam and aluminum heads to bleed off. Go to aviation fuel or cut back the compression. Or a cam with wayyyy more overlap :p
 
NewABodyFan said:
If by stating E heads, you mean Eddy's, then you don't have a head problem you have a compression issue. If your at sea level about 10 to 1 or 10.5 to one is all your going to be able to get away with on pump gas and aluminum heads, 9 to one on iron heads. If you go to indys, your going to get the same results unless you go way up on your chamber size. You need to pull the pistons our and take some metal off if you want to run pump gas on the street. If you don't, and want to run race gas, then let the good times roll. We are at 4500 feet, and I have done a lot of playing around with compression and aluminum heads, the most we can get away with is 11.5 to one with a big cam. That is real border line, 11 to one is the best bet. But our air is very seldom below 6000ft in the summer.

Earl
Click to expand...

Where do you get this kind of information? I'm not going to be too hard on you, but come on!

Sounds like you have been listening to too many chevy guys.

9 to one with iron heads?......then why do I run 10.65 to one with my iron heads? I'm not at sea level, but I run a solid cam on 93 octane gas with no problems.

Also, to the post before mine.......OVERLAP has NOTHING and I mean NOTHING to do with it.

Please people, don't regurgitate(sp) what others say, unless you understand it.

The closing point of the intake valve is one of the most critical points in building compression in a motor. Tell me what OVERLAP on the EXHAUST stroke has to do with building compression!

Sorry for the rant.....I couldn't take it anymore
 
Hey Larry! how are things going for you? I'm in a mess again with the car. Typical :lol: I decided to create a monster to putt around the streets with. I ordered a cam From Scott Brown today. Between him and Ryan J I should have things straighten'd out.
 
That part was actually a joke. Too bad you missed it and decided to rant on instead. Generally a smilie face is intended to suggest humor.

What I wanted to imply is a cam that held both the intake and exhaust valves off their seats for 360 degrees of crank rotation. This would eliminate too much compression by virtue that it would be impossible for the engine to make compression. A joke nothing more.
 
Well Mr. Bench Racer, I guess you name says it all. First, in my area the last time we saw 93 octane gas was 5 years a go. So we deal with 91 octane gas. I would be willing to bet that you might think you have 10.65, but if it was measured correctely that you would find less compression. If you do have 10.65, which you might, and your at altitude, then you could get away with it on 93 octane.

I would not start accusing people of not understand engine theory until you know who your talking with. Cam overlap has everything in the world to do with static compression VS dynamic compression. It is very obvious from your responce, that you don't understand the differance.

I would be willing to bet I was building Mopar motors before you were even born.

Here are a couple of links that might futher your edcuation on real world engine building.

Cam timing VS Compression ratio
http://victorylibrary.com/mopar/cam-tech-c.htm

So in closing, no sweat with the rant, I find it quite amusing, much like the comedian that first coined the term.

Don't go off on people about things you "think" you know about. It is better to keep your mouth shut and let people think your a fool, than open your mouth and remove all doubt.

Happy Moparing.

Earl
 
A longer duration on the intake side with a later closeing intake valve might bleed off enough compression to run without pinging. The overlap happens at the end of exhaust/begining of intake cycle and actually raises the compression at some point in the RPM range.
I run 10.5-10.65 to 1 on 93 at sea level +600 with iron heads but have .037 quench area and its drag race only. It may be detonating,who can hear it with open headers? Its holding together so far.
Has anyone tried running E85 fuel mixed with premium? Ethanol burns cooler,has a 110 octane rateing,and should be cheaper than race fuel and leagal to run. You would need to increase fuel flow by 20% or so because ethanol contains O2 so mileage would be poorer.
And Brett you can buy E85 in WBurlington. I havent tried this myself but am trying to research it. Claims of 5 to 10% more HP are the rumor. A methanol carb might work if jetted down. Just rambling.
 
I'm not a confrontational person. I just wanted to express my opinion very strongly. Sorry to get everybody's feathers in a ruffle.

I guess I did miss the joke.....sorry about that, I'm pretty slow sometimes.

I do have 93 octane gas and the altitude around here is about 900ft.

You probably were working on cars before I was born.....I'm still young.

I do know what I'm talking about.

I DO have 10.65 compression....I've build and measured a bunch of engines in my short time on this earth.

Like I stated, OVERLAP has very very little to do with building combustion pressure......INTAKE CLOSING POINT has WAY more to do with it!!!!!!!
Change the overlap by 2 degrees and you'll see almost no difference, Change the Intake closing point by 2 degrees, and you'll get a measureable difference.

I don't know what you mean by the "bench racer" comment. Those are just assigned based on the number of post/replies youve done. I didn't label myself with it! Or maybe I just don't know what I'm talking about again....right?


Once again, Sorry!
 
Brett,

I just came over here yesterday to see what's been going on. I got caught up with what you've been up to.

Looks like you are going right after those 10's with a stick!

Good luck. YOur car WILL do it!

Later,

Larry
 
LAR_414 - Apologe accepted - and I will be the first to give you mine if I took your post incorrectely. That is one thing I hate about a email type post - tone is impossiable to interject into the message.

When I made the statement that duration will effect dynamic compression, it was directed more toward cam choice to start with when building a motor. A long duration cam with marginal compression is normaly not a good choice, since it will contribute to the marginal compression issue.

I consider 900' sealevel. Our altitude is 4500', so compression choice and cam duration become very critical for performance. A good day is 6000' adjusted, most of the time we are racing at 8200' adjusted and above. It is very hard to build a motor that will run at this altitude and still let us travel to a sealevel track without changing the motor. Which can be a chore in a door slamer

I am glad that young guys like you are involved with old Mopars. It seems that the Mopar thing is getting to be a old man thing. Again I will say that I am sorry if we got off on a wrong foot here. If there is anything I can do to help you and your efforts, please let me know.

Earl Helm
Crew Cheif
Mott Motor Sports BA/FMD
 
Glad you two found some common ground. Earl you sound like you know what your talking about and I can tell you that Larry (Lar414) know's his stuff too. I have known him quite a while. As for me whatever you guy's said?? ain't got a clue :lol: I do a little wrenching and am real good at extending my right foot! :thumrigh:
 
You must log in or register to reply here.
-

Back
Top