Detonation Problems in my GTS

[Brad Manhattan Beach]

Does anyone have any experience or suggestions on how to solve my detonation problems on my '96 GTS?

Dan Cragin put cleaners in numerous times with absolutely no luck. He eventually got approval to pull the heads and machine down some outcroppings from the factory casting (the original authorization was to pull the engine and return it to Arrow). I also paid extra money to do a 3 angle valve job and to polish the bowls (all within factory specs so I wouldn't void the extended warranty). I did see that when Dan pulled the heads, that there was a very significant amount of carbon that had built up on the top of the rear pistons.

Well since then CA gas has gotten worse (gone down to 91 octane) and my detonation is very noticeable. While doing a dyno run at R&D Dyno the detonation really became prevalent(and I had a can of octane booster in the tank at the time). They told me that it was probably robbing some serious HP from my engine.

I have been told by a petroleum/fuel engineer that the problems lie in the fact that the engine temperatures are too high (my car runs consistantly at just over 200 degrees), and the carbon build-up is bumping up my compression. He recommended the long term soltion of going to a lower temperature thermostat, and going to a larger radiator.

I have also been told that a couple of mechanic tricks to try include running water into a vacumn hose that would be basically like steam cleaning the carbon out. The other trick that I heard was running ATF into the same vacumn hose to achieve the same effect. Have any of you heard of these trick or tried them on your cars?

Has anyone had this problem and solved it without sending the engine back to Arrow? If your engine had to be sent back, what exactly did Arrow do to solve the problems? I will probably try to contact Arrow Racing tomorrow to ask their advice.

Thanks in advance for your attention and feedback.

Brad

 

[Ulysses]

I have heard of the water trick and have tried it on a different vehicle. It works pretty good. Haven't heard of using ATF. Mine is usually above the 200 mark on long mountainous drives and running high RPM in third. On hot days, it stays above the 200 mark also. Never had detonation problems. Though it won't hurt to add a bigger radiator, I doubt it will solve your detonation problem. From what I have read here, a lower thermostat won't do anything for your temps, it'll just open the valve sooner. The bigger radiator is the way to go to lower the temps (or Roe Racings cooling mod, but that requires cutting the facia).

 

[genXgts]

hey Brad, for what it's worth try adding some Redline water wetter to the mix, lowers operating temp by up to 20 degrees or so in some cases. The lower thermostat will not do much once the temp gets up to operating, well past the switch temp, so it's a moot point I would think......

 

[Ron Hickey]

I had a detonation problem on my 97 GTS. It was noticeable just below WOT under hard acceleration. I tried all kinds of cleaners like BG-44, etc. Also replaced the plugs, wires, cleaned the throttle bodies, etc. No luck. Finally, I took it in to another Viper tech. He diagnosed the problem as a leaky intake manifold gasket. He replaced it, and the problem was solved. (Yes, I had the IM gaskets replaced two years prior to that as per the TSB.) Don't know if my remedy will work for you, but it might be worth a shot. Otherwise, perhaps going to a colder plug will help. (I think NGK makes one.)

 

[LTHL VPR]

Brad-
Sorry to hear about teh detonation problems.
Sounds like you are on the right track....
For reference, any of our high performance packages include an upgraded radiator and thermo to keep engine temps down. Even with our 650 package on, the temps stay around 180 during normal driving conditions.

The fuel in CA is terrible, and although the drop from 92 to 91 Octane may not sound like much, it is.

Here are some recommendations for you (least expensive to most expensive, and recommended in this order):
1) Try a colder spark plug. We have some in stock if you want us to send a set down to you.

2) Not sure what Octane booster you are using, but all the 'off-the-shelf' ones we have tested have been crap. We only use race fuel concentrates, which are much different than an octane booster. With the recent 91 Octane change in CA, we have trouble keeping it in stock. It comes in a can and you only need to use about 1/2 can per tank fill. Does not foul oxygen sensors or plugs like octane boosters often can. We can send you down some if you are interested.

3) Next I would try some fine tuning of your PCM and make sure your car is getting enough fuel in the first place (dyno runs with Air-Fuel measurements). 96's tend to run more lean than current models and this may be the culprit

4) Try upgrading your radiator, rad. fan (since you have a 96 fan which is smaller than curent ones) and thermo. to improve cooling


Couple questions: What mods do you have on your car? How hard do you drive it? Is it for street or track or both?

P.S. Since you indicate it is a 96, whatever the outcome is, it may be a good idea to upgrade your fan to the larger style found in 98+ Vipers to keep engine temps down.

Let me know if we can help.
We're in Nor Cal and could either send you down some of these options or, if you have a couple days, bring it up, and we can take care of it at our shop.

Good Luck!
-Wayne (LTHL VPR)

 

[Bad_Byte]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by LTHL VPR:

2) Not sure what Octane booster you are using, but all the 'off-the-shelf' ones we have tested have been crap. We only use race fuel concentrates, which are much different than an octane booster. With the recent 91 Octane change in CA, we have trouble keeping it in stock.
<HR></BLOCKQUOTE>

Wayne being in Calif. myself I'd be interested in the octane booster. I only have two question

1. Does it have any adverse affects on the smog-ability of the car in other words does it affect the cat converter? and

2. What's the cost?

Thanks in advance.

Art

 

[Doug Supercharged Vipers]

Brad -

Did you cc your heads when you removed them? Too much compression will detonate under higher temps, lower octane fuels and too much timing. Have you checked the fuel pressure under WOT and blue printed the injectors? Water injection may help as it provides as an anti-detonant to cool down higher cylinder temps.

Your always welcome to call me, it's been a while since we last spoke.

Doug

 

[Leonard Knight]

Hi Brad. Sorry to hear about the detonation problem. I had the same thing with my 96GTS. Ended up having the heads removed and the carbon cleaned out. That has worked for the last 10,000 miles although up until last year it was on the track for viper days. Helps to clean things out. I would be careful with the ATF. I do know that the water injection helps. Sounds like the larger radiator is the way to go but do try the water wetter first. Really helps.

Leonard

 

[Paul Hawker]

Brad...If Arrow is offering to service your motor for free, I would go for it in a big way. I know it is a hassle to have your car out of service for 6 weeks, but it is a great long term investment. They will check each and every part, and upgrade anything suspect. Larger radiator, etc, are just bandaids for what could be a more serious issue.
Cars usually run stronger, and smoother after Arrow works their magic on them.

 

[Leonard Knight]

Brad:

I had the original work done by Dave Jenkins. I know it is difficult to get down there. I have been using Dan Cragin at The Viper Shop recently as the car is out of warranty. I don't know if Dan can do warranty work yet but I know he is looking into it. I would take Paul's advice and if they are offering to do the work at Arrow, go for it. I don't think they are taking quite as long these days to return the motors.

Leonard

 

[Brad Manhattan Beach]

Thanks Paul and Leonard:

I will try to get the case reopened with my extended warranty using Dan's documentation.

I will let you know how it progresses. Any additional input would be appreciated. You can also email me at [email protected] .

Take care,

Brad

 

[Greg W]

Brad,
I'm in So. Calif., San Diego. I have definitely had a detonation problem with my '94 RT/10. The start of the problem seems to be suspiciously close to when Calif decreased the octane some months back.

Regarding the pre-ignition problems, there was a very interesting article in Dec. 2001 Hot Rod Magazine in which they compared performance versus different octane level gas, with and without the use of octane boosters. They were thorough enough to reset the timing for each octane level, searching for the best combinations. Basically the octane boosters don't do much. (BTW, there appears to be a misleading claim used by virtually all of the manufacturers of octane boosters: when
they say that their product will increase the octane level by "3 points",it really means an increase of 0.3, i.e. from 91 octane to 91.3 not 94).

I spoke with the makers of Trick racing fuels regarding their octane booster, and it became pretty obvious that they were reluctant to recommend any boosters, including their own product. They basically said that you'd need to add a huge amount of booster to get anything approaching the octane levels of any of the good racing fuels.

I will soon try higher octane racing fuel mixed with the 91 type, I will post the results.

Good luck,

Greg W.

 

[Brad Manhattan Beach]

Hi Everyone:

Thanks for all of your feedback.

First off, my car is almost completely stock (except for the K&N, smooth tubes and the 3 angle valve job). I use it as a daily driver and visit the track a few times a year.

GenX, I have tried Redline Water Wetter in my car before and have not seen much in terms of results (using distilled water).

Doug, I did not mill the heads (if that is what you are referring to).

It sounds like my immediate options are to have the dealer clean out the carbon again and start with upgrading the cooling system fan and radiator.

Wayne, will the octane booster resolve future build-up of carbon in my engine? I am very inetrested in what your results have been with CA street cars. Will it cook my cats?

Ulysses, my GTS seems to run just over 200 degreees all of the time. When I drive the car hard through the mountains or on the track it goes up around 220.

Ron, I will have the intake manifold checked out. Did this have any adverse effect other than the detonation (like carbon build up)?

Leonard, are you taking your car to Dave Jenkins to work on your car? Living in Manhattan Beach, it is very difficult to coordinate the logistics to use him or someone in the SF Valley. Do you have any Viper techs in the South Bay area? The folks at Glen Thomas Dodge don't seem to have much experience in these matters (even though they are Viper certified (or at least claim to be). I heard that Don Kott (in Carson) is servicing Vipers now.

Is there anything that the folks at Arrow can do to permanently fix this this problem, or is this something that I have got to deal with every 10,000 miles? Does anyone have a contact at Arrow that I can talk to on this? If I am going to have this thing sent out to Arrow, I certainly don't want this thing to occur again.

I guess that the cold plugs are my immediate fix. What do you guys recommend? Is NGK the best option (or the only option)?

The larger radiator and fan changes will have to wait until I find some employment.

Thanks all for your attention and feedback.

Brad

 

[Brad Manhattan Beach]

Greg:

Thanks for your feedback.

The latest speculation on my detonation problems from Arrow racing include:
- blow-by occurring via cylinder jackets (which was common in '96 GTS's)
- Leaking oil in the intake manifold (which lowers fuel octane)
- Internal coolant leak (also possibly the intake manifold gasket)

I put in two bottles of Water Wetter into the car, and it still runs past the third hash mark above the 190 degree label.

The car goes in on Monday to be checked out. I'll keep you posted.

Thanks again for you feedback.

Brad

 

[Hisser]

I had the same problem but changed the spark plugs to a colder plug and that seemed to work. BUT, it only started when I modified the airbox so go figure.

 

[Greg W]

Brad,

I may have gotten lucky. From the info posted here on the intake manifold gasket problem, I decided to torque mine down a little bit. I found 3-4 bolts quite loose.

Maybe it's wishful thinking, but I didn't hear/feel any detonation on numerous full throttle runs since the bolt tightening. I'm crossing my fingers, it could be that simple for me.

I bought some 100 octane Trick unleaded, but haven't mixed it in yet. Hopefully won't have too!

Greg W

 

[Brad Manhattan Beach]

Well the factory gave us final approval to pull the engine and send it back to Arrow. They injected dye into the coolant and crank case and found blue spark plugs.

The car is definitely losing oil to blow-by or a significant leak into the combustion chambers. They also found the engine to have internal coolant leaks.

The funny thing is that the people at Arrow will not install roller rockers on the new engine even when I want to pay for it. Does anyone know why? Are there any extra things that Arrow can perform on the engine (if I pay for it) that are worth doing? What kinds of documentation can I expect back from Arrow on the new engine? Can I (or should I) request that a specific person do the rebuild on my engine?

I also am considering swapping out the flywheel and clutch before the engine is re-installed into my car. What is the best flywheel and clutch combination for my Snake if I use it as a daily driver (with regular visits to the road race track)? What is the upside and downside to this solution?

I drove a friend's GTS with a new flywheel and I noticed that the engine spooled up much quicker and smoother than the stock one. It also seemed to remove the dead spots in the powerband. Is this the case with all flywheel upgrades?

Thanks everyone for your feedback.

Brad

 

[David Jenkins]

Brad,I got a '96 GTS here with the same deal. Best to get it done now. Throw in at least a flywheel,stock clutch and baffle the pan. I'm doing a motor on a '96 RT with 90k on it. Sent it back for the head gaskets and they sent this guy a whole new bullet. He's got a $50 deduct contract!dj

 

[Brad Manhattan Beach]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by David Jenkins:
Brad,I got a '96 GTS here with the same deal. Best to get it done now. Throw in at least a flywheel,stock clutch and baffle the pan. I'm doing a motor on a '96 RT with 90k on it. Sent it back for the head gaskets and they sent this guy a whole new bullet. He's got a $50 deduct contract!dj

<HR></BLOCKQUOTE>

Dave:

Thanks for the feedback. Is Dodge having the engine rebuild or replaced?

I will definitely go with the flywheel and clutch. Which ones do you recommend? Who's baffled pan do you recommend? How much do these things cost? Cash is tight since I have been unemployed for some time.

I would have brought my car to you originally, but logistics made it very difficult.

Do you have any recommendations about how to stay in touch with Arrow? I have been talking to Todd. Is there anything extra that Arrow can do to the engine while it is being rebuild? What kind of documentation will I get back from arrow? Will they give me all of the specs of the new engine (as well as their dyno #'s)? I hope that they will be building the engine to '96 specs, and not 2002 (i.e. cam and forged pistons).

I have a $0 deductible... thank God. Thanks for your feedback Dave.

Brad

 

[Y2K5SRT]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Brad Manhattan Beach:
Do you have any recommendations about how to stay in touch with Arrow? I have been talking to Todd. Is there anything extra that Arrow can do to the engine while it is being rebuild? What kind of documentation will I get back from arrow? Will they give me all of the specs of the new engine (as well as their dyno #'s)? I hope that they will be building the engine to '96 specs, and not 2002 (i.e. cam and forged pistons).
<HR></BLOCKQUOTE>

Having gone the Arrow route myself, I think I can add a little here. Staying in touch with Arrow? I was told that the dealer is THE contact with Arrow and that the customer's are generally not given access to them at all. I tried, to no avail. The one thing I did do (kinda fun) was include a note with the latest dyno sheets. I begged them to keep me in Ferrari-killing trim. The letter was sent with the motor to Arrow. Extra stuff? I was told absolutely not. Because it is warranty they cannot add or do anything outside of the warranty work, even if you offer to pay (and I did). Documentation: You are totally dependent on the servicing dealership. Most (95%+) of the engines do not come back with ANY documentation. I begged, pleaded, and tried to bribe my dealership for the new specs - all to no avail (Bill Pemberton, I still forgive you). Others have been luckier and got a detailed list of the exact repairs/replacements made. They also noted all of the problems when it came in. The one person I know who successfully got this paperwork was Ron (SoCal Rebel) and you can read more about it on this thread. As to "new" parts, I believe that you will get the "right" parts for your car - cam, pistons, etc. You will not have a '96 creampuff.

Hope this helps!

Chris

PS. Sorry to hear about the job situation. Recently been there, done that. It will work out for the best, of course.

 

[Tom F&L GoR]

Brad, hope you're on the road soon.

All, please don't use ATF to clean combustion chambers, ATF is simply a good quality, fairly light mineral oil with a small amount of additive for oxidation protection, cleanliness, and antiwear... There's nothing in it that would clean heads or pistons, probably only make them worse.

And in hindsight, if the engine knocks at WOT, it probably isn't the intake manifold gasket, since a) manifold vacuum is low and would pull less through a leak, and b) engine doesn't care anymore since TPS and MAP sensor would correctly signal max air consumption (whether through the throttle or a leak) and request tha matching max fuel rate. If it knocked at part throttle and not at WOT, then maybe the gaskets...

 

[v8huntr]

maybe colder plugs will help.

 

[Brad Manhattan Beach]

Well folks, I just got off of the phone with Todd at Arrow Racing to find out the status of my engine rebuild.

He basically told me that my engine had some of the worst corrosion that they had ever seen. The water pump was badly corroded, engine block had corrosion damage, as well as other coolant leaks. When I told him that all I ran in my engine was distilled water and water wetter he was not surprised. He said that he had a few other engines with corrosion damage that were using it too. He said that the damage was almost bad enough to write off the entire engine. Of course my worry was more related to writing off the engine and not having the serial numbers match up.

To verify the subject of this discussion, the engine was getting oil leakage due to blow-by in several cylinders. There was also a significant build up of carbon in the combustion chambers. Detonation was definitely due to oil getting into the chambers and dropping the octane significantly.

Has anyone else experienced these kinds of problems? I was pretty shocked to hear that water wetter had something to do with corroding the water pump housing, the thermostat housing and engine block (and just about anything else that was aluminum).

I just thought that I should give all of you water wetter fans a heads up.

Brad

 

[shifter]

Brad
I think the problem is more related to using just water, than the water wetter itself (though I'm sure it didn't help). You should use Glycol with silicates (traditional coolant)in your cooling system. Traditional coolant has glycol, which increases the freezing point of the water and increases the boiling point of the water, and contains silicates. The silicates distribute through the aluminum and copper/brass cooling circuit and form a very thin layer over the aluminum to protect it from corrosion. Al corrodes very easily, and is sacrificial to iron, carbon, and brass (with copper being the next easiest to corrode after Al).

The new coolants (oat, GO5) use a few chemicals to create a reaction when corrosion attacks aluminum. The reaction then breaks down the corrosion and protects the aluminum. It's more environmentally friendly than the silicate version, but doesn't provide as good of corrosion protection. You can tell the new coolants by their color (brown/gold). I also would not recommend using the new coolants in any system that doesn't come from the factory with the new coolant (and i don't think any Vipers to date have). Since the corrosion protection isn't as good as the silicate version, some of the components in the cooling system might need to be re-designed to protect for the reduced corrosion protection.

Racecars primarily use 100% water to keep tracks free of slick glycol, not because water alone is superior.

 

[HSSSTOY]

..Why are you using distilled water in the radiator??? my guess is the distilled water is causing all the damage.. let me explain. Distilled water has the affinity to rob ions out of metals it is in contact with over time i.e corrosion. I think the culbret in this situation is the distilled water,not redline wetter my opinnion as a chemist..


-----------
99 SLV./CON. GTS

 

[Hoosier Daddy]

I'll throw this out for the experts, maybe they can chime in. I use this stuff called Carbon Guard on my 250Hp outboard motor by mixing some with the gasoline. Prevents carbon buildup and can loosen up harmful deposits if present. Would this work on a car engine?

 

[Brad Manhattan Beach]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by HSSSTOY:
..Why are you using distilled water in the radiator??? my guess is the distilled water is causing all the damage.. let me explain. Distilled water has the affinity to rob ions out of metals it is in contact with over time i.e corrosion. I think the culbret in this situation is the distilled water,not redline wetter my opinnion as a chemist..
-----------
99 SLV./CON. GTS

<HR></BLOCKQUOTE>

Interesting because I used distilled water to avoid hard water deposits in the system. It never caused any problems with any other cars, but then again they weren't aluminum engines (except maybe the heads). The distilled water was used for about a year, until a hose blew. Upon replacement, the shop used regular water. I didn't realize that there were those kinds of downsides. Also used Neo coolant additives with lubricants.

Thanks for the feedback. I will remember it when I get the motor back. What is the best coolant for warm weather cars? I live in Southern Cal and there is no need for anti-freeze.

Brad

 

[shifter]

Brad,
Divorce the term anti-freeze from coolant. Coolant does much more than provide sub-zero freeze protection. It also provides overboil protection, and corrosion protection. Use the traditional sweet smelling green coolant available at any auto parts store. I know you don't need it for it's antifreeze properties, you need it for corrosion protection and it's overboil protection.

 

[Brad Manhattan Beach]

Thanks everyone for the feedback. I'll stick to the standard anti-freeze solutions that the dealership puts into the Snake. I don't think that based on the feedback from Arrow that I will be using Water Wetter in the future.

Just a final note, that I tried the distilled water and Water Wetter experiment after I blew two radiator hoses. The experiment lasted all of 4 months, in an effort to bring my engine temperatures down. I later found out from Arrow that one of the reasons for my temperature problems was an internal coolant leak. The one constant is that I have run Water Wetter since day one of owning my GTS Coupe.

Per the damage report from Arrow, the detonation was caused by oil blow-by past the second ring into the combustion chambers on multiple cylinders. Further leakage might have been caused by the heads being torqued down with the incorrect specs. The block was sent back to the manufactuer for redecking, liner replacement and weld repair. Corrosion damage to the engine was severe, and the use of water wetter was noted.

If anyone would like more details, please email me.

Brad