Popping In Exhaust Around 5,500 RPM

[DeadLifter]

I'm gettin popping in my exhaust and power loss in upper rpms's. I think if it was excess gas in the exhaust like I'm seeing most people say on here I wouldn't be gettin power loss. I bumped the fuel pressure up to around 42# with vac line off, new plugs, and newer MSD Super Conductor wires. Gonna try cap and rotor. Could it be Casper electronics throttle enhancer, or should I check timing (I'm only runnin 87 octane) maybe back it off a hair not sure what it's set at between 12 or 14 I think.
Any other suggestions?

 

[95GTV8]

popping or pinging?

 

[DeadLifter]

99% sure it's popping. If it was pinging wouldn't it do it when it's under load at a low rpm when accelerating hard? It only does it around 5,500 rpm.
I know what pinging is, but I've never heard it so I'm not completely sure.

 

[divit250r]

Are you running stock valve springs? Might be floating the valves...

Scott

 

[DeadLifter]

I was kinda wondering that myself about floating valves.

 

[DeadLifter]

It's not the throttle enhancer. Sounds kinda like you're stompin on a ball of bubble wrap when it happens kinda hard to explain. Not a backfire or anything like that.

 

[DeadLifter]

Backing timing off did nothin either. How do I know if it's that valves floating?

 

[NastE50]

I have the same problem. I can't figure it out either. Its been like this for a while. My RPM is a little lower, like 4,000.

 

[94 Cobra 5.0]

Subscribing. Same problem here, happens to me right around 4,000 to 4,300 Does it happen all the time or just once and a while. Mine only does it once and a while.

 

[maximos]

i have the same sound, but it only happens every once in awhile when i down shift -- happened before i put the exhaust on then went away for awhile, now it's back

 

[Swarzkopf]

Sounds like it might be detonation based on your description of the sound...

How do your plugs look? That can tell you alot about the tune and condition of your motor.

Monitoring the air/fuel ratio with a wideband would probably be a smart move as well.

Good luck.

 

[DeadLifter]

It doesn't go away on my car 5,500 rpm everytime. A better description of the sound would be like a handfull of gravel flying through the exhaust. I'm startin to think my cam is too much for the stock valve springs.
Plugs look fine, just changed them and old ones looked good too.

 

[95snoozer]

valve float

what cam? what springs?

 

[DeadLifter]

I was told the cam was a stage 2 TrickFlow, but that might not be right. I do know it's not stock. I believe the springs are stock.

 

[Black95GTS]

I was told the cam was a stage 2 TrickFlow, but that might not be right. I do know it's not stock. I believe the springs are stock.

That is definately valve float. The only cam that stock springs should be used on is the stock cam. You definately need stiffer springs for a TFS Stage 2 cam.

Adam

 

[DeadLifter]

I see that TFS has a set of springs for stock heads in Summit for about $100.
Not really gonna worry about it for a little while I don't really run my car that high often, but knowin the problem was there and not knowin what it was was buggin me. Hate to have to change those things kinda of a pain, but I'll get it done sooner or later.
Thanks

 

[95snoozer]

get the stage 2 springs if you even THINK it might have a stage 2 cam

that is most likely your problem and its dangerous

 

[DeadLifter]

These are what I was looking from TFS.

at.http://store.summitracing.com/partdetail.asp?autofilter=1&part=TFS-2500100&N=303787+115&autoview=sku

Or will one of these work better. And with these do you know if i could reuse stock parts to install them.

http://www.latemodelrestoration.com...a.pvx?;item?item_no=M6513A351 1&comp=LRS

http://www.latemodelrestoration.com...a.pvx?;item?item_no=M6513A50 1&comp=LRS

 

[95snoozer]

high performance... lol

get the stage 2 springs, not stage 1

 

[DeadLifter]

Where do I get the stage II springs?