Engine knock on the track

[ntmatter]

During my most recent lapping day, I noticed that I was getting some engine knock when I dropped the hammer going into the front straightaway. I was, of course, running Super Unleaded gas, which is 92 octane in Washington. It seems to me that a Viper shouldn't knock under WOT, even on the track, but could I have been doing something wrong? Does anyone know if it is possible to have problems either with your driving style or engine setup that might cause this problem? Also, should I consider a higher octane gas, or some sort of octane booster to combat this problem? Finally, could this be a warranty issue of some sort?

Thanks for any advice,

Andy

 

[Leonard Knight]

Andy: Are you talking about pinging type knock or a rod type knock. I am not sure on the 98 but my 96GTS had to have the heads removed to clean up the deposits that had built up in only about 5000 miles when I first got the car. Since then I have not had the problem.

If it is a rod type knock it could be oil starvation. I don't remember the year when they made the change to the oil pan but I had to update mine for use on the track. You might ask your dealer about this or perhaps someone else can answer about the year. I know Jon B. at Parts Rack has the pans and can answer any question about the year.

Hope this helps.

 

[JonB]

Andy.......sheesh, I have been IN your car, and did not notice it was a 1998 Silver...I thot Dodge did not make silve til 99 is why I ask. I hope it is pinging (detonation) and not knock---
see if you have oxygenated fuels in Seattle area year round.....yuck.

The 1996.6, 1997, 1998, and 1999 are definitely plagued in high-G force events by oil stratification-starvation. Their low-capacity oilpans (designed to help save weight in GenII) do not have enough oil for the time that G-forces "trap" the oil in the various upper motor regions, and/or in the pan corners.

I have had numerous dealer inquires and customer inquires (mostly from CA) after motors indeed knocked a bit, and later #3, #2, or #1 rod {in that order] 'air-cooled' the block.

Back on the OLD VCA board, in 1999, I began warning of this.
[Note to moderators....could we have a SYMPTOM-DIAGNOSIS archive soon??] The fix is 3 stages for 1996.5-1999 Vipers. All are direct bolt-in mods, done in just a few minutes:

Stage 1: higher capacity(+1.4qt) oil pan; improved-draining and improved scraping windage (scraper) tray. $599 including a billet aluminum 'lifetime' gasket. List well over $900.

Stage 2: Trap-door oil pan upgrade kit;laser-cut drain tray to better align with and utilize the improved windage tray of Stage 1: $399. $349 when bought with any other stage.$299 w/ all 3.

Stage 3: Higher-pressure oil filter adapter. Add up to 5lbs at idle and 12 psi at 5000 RPM. Cooler oil, too. Too long to type, so ask me why! Direct bolt-on, includes bolts/gasket. Cheap protection at $259.

2000+ Vipers can benefit from Stage 2 and 3....you already have Stage 1, you lucky creampuffs! No ACR needs stage 3....

 

[Double Venom]

I too hope it is a simple case of "ping" vs. knock. We learned the hard way! Who would have thought a "kit-car" would be able to pull a +1.2G on Yokohama street tires no less !?

Fortunately we had a pro testing the car at TRC who could feel the engine getting tight. Pulled up to the trailer and it was running just fine. Turned it off, then back on and it wanted to start but sounded like an engine with a drained battery.

Pulled the pan back at the shop and found, unlike most guys that experience this, #1 & #2 bearings fried. Didn't spin and didn't loose a rod or the crank!

I assure you, I now memorize every word JonB says. As we see it, there are two choices, stay off the autocross / roadcourse tracks, or upgrade the oil system!

DV
P.s. JonB, thanks again for your help and wonderfull service!

 

[ntmatter]

Jon,

Although I can't make it to the next PIR track event, I'd like to see if you'd be available for a few laps so that you can have a listen. Being reasonably new to this sort of thing, I don't really know the difference between a ping and a knock. All I know is that I'd get a clackety-tickety sound when I jumped on the gas on the strait. I'll definitely add oil (along with brake) upgrades to my list of things to do over the winter, though.

A.

 

[ntmatter]

A quick question about the Oil upgrades - is this something that a reasonably handy person (such as yours truly) could do as a bold on upgrade (at least stage 1 and stage 2), or should I have a Viper Tech do it?

A

 

[Chuck 98 RT/10]

Assuming that it is detonation, try gas from another station. Gas is like beer, there's good beer and bad beer. Amoco and Guiness are preferred.

Most tracks have high octane fuel available. Very expensive but try some the next time, take a few laps and see if the pinging/knock goes away.