Car Took A Dump on the Dyno

SYNFULL · May 23, 2008

Sean,
I have ordered many other products and spent plenty of money with your company.
I knew there was a problem and I was trying to get help from wherever I could. I sent you and Tony my log files and the profile I was using. I am new to tuning - I just wish one of you said let's play it safe and take enough timing out if it's detonating until it's straightened out. It would have taken just a few minutes to make the adjustment and email it to me. That being said- I did take this project on and it's my responsibility that I did damage to my car. That's the risk I took. Unfortunately I didn't have many options. There are not any Viper tuners anywhere near this area. I considered having my car trailered to a tuner but that was almost 2k. Luckily it's not anything permanent, and I have found someone that knows what he is doing with tuning and has a dyno- just hasn't worked on a viper before.

Thanks
Gary

Sean Roe said:
That's a great point.
Something has been very different about this since the beginning. Seeing the VEC log and seeing that the box saw no manifold pressure input was the first problem (no fuel enrichment and no timing changes while driving with the SC). If the cc's on the heads are lower, could be part two of the problem. The stock cc's are 74 (yielding 9.6:1). Make sure they're no lower than that if they come off for new gaskets. Also, go 10 ft/lbs over the stock torque on the head bolts.

Gary, sorry if you felt like I was getting shorter with you after all the emails. I was just running out of the time I could give away. Hard to pay the bills when you don't sell the parts to the person, but still provide the service.

Regards,
Sean

plumcrazy · May 23, 2008

where is that shop by the way ? in pa ?

Simms · May 23, 2008

Gary, sorry to hear about your dyno experience. Hopefully not too much damage was done. I know your frustration, but check out the things Tony and Sean are recommending.

There is a guy hear in Pittsburgh that has worked on vipers before. It's not his bread and butter, but if ever in need, I can get you his info.

SYNFULL · May 23, 2008

plumcrazy said:
where is that shop by the way ? in pa ?

JD automotive- The guy will be an experienced viper tuner when I get done him

jds-high-performance.com

Jack B · May 25, 2008

SYNFULL said:
JD automotive- The guy will be an experienced viper tuner when I get done him
JD's Auto Repair and Performance Center

If I could make a couple of humble suggestions. I am running a 350 rear wheel shot on a 525 NA rwhp engine and have the same concerns that you have. Your investment is large, and every safeguard should be considered, here are a couple of recommendations that should be considered.

A. A dual wideband set-up with logging capability. You will see severe detonation in a log with fast widebands. As important is the ability to log the a/f on both sides of the engine, this is especially true on an aftermarket SC set-up.

B. If you have to pull the heads, a head-stud kit from ARP should be looked at. They have a very good write-up on their website, as a matter of fact it is an eye opener.

Getting back to what has been said, knowing the combustion chamber size is imperative.

SYNFULL · May 26, 2008

Thanks Jack. I will be looking to address all of those items. Quick question- does it matter what size the combustion chambers are if the car is tuned for them?
Gary

Jack B said:
If I could make a couple of humble suggestions. I am running a 350 rear wheel shot on a 525 NA rwhp engine and have the same concerns that you have. Your investment is large, and every safeguard should be considered, here are a couple of recommendations that should be considered.

A. A dual wideband set-up with logging capability. You will see severe detonation in a log with fast widebands. As important is the ability to log the a/f on both sides of the engine, this is especially true on an aftermarket SC set-up.

B. If you have to pull the heads, a head-stud kit from ARP should be looked at. They have a very good write-up on their website, as a matter of fact it is an eye opener.

Getting back to what has been said, knowing the combustion chamber size is imperative.

Jack B · May 26, 2008

SYNFULL said:
Thanks Jack. I will be looking to address all of those items. Quick question- does it matter what size the combustion chambers are if the car is tuned for them?
Gary

Depending on the chamber size, you will could already be starting out with too high of a compression ratio, therefore, promoting detonation. I truly hope all is well with your engine.

A heads up in case you go with a head stud kit. You will have to clean out the bolt holes in the block. Do not use a tap, ARP has a thread cleaning tool.

v10kingsnake · May 28, 2008

Sorry to bump a falling thread but I had great experience using JD's in Phila. when it came to tuning my 2003 Cobra. At the time I inquired about them messing with a Viper but they had not at the time a couple years back. They are very well known and greatly respected in the Cobra world on this coast so I would expect that reputation to carry over in helping your situation. Good luck.

PAvenomRT/10 · May 28, 2008

Where did you take the car to be dynoed? I am also in Bucks Co. and wondered if it was someplace local.
thanks,
PAvenom RT/10

SYNFULL · May 28, 2008

PAvenomRT/10 said:
Where did you take the car to be dynoed? I am also in Bucks Co. and wondered if it was someplace local.
thanks,
PAvenom RT/10

Yes they are local in Huntingdon Valley on rte 63. They will know Vipers when I get done with them. :omg:

JD's Auto Repair and Performance Center

v10kingsnake said:
Sorry to bump a falling thread but I had great experience using JD's in Phila. when it came to tuning my 2003 Cobra. At the time I inquired about them messing with a Viper but they had not at the time a couple years back. They are very well known and greatly respected in the Cobra world on this coast so I would expect that reputation to carry over in helping your situation. Good luck.

V10 Thanks for the info. They were one of the only places around I could find with a dyno. Joe - the owner took a few minutes to get the hang of the Roe software and worked with Marcellus on the tune and Dyno. I could see he knew what was going on as we were watching the logging on the laptop and I was feeling really good and confident until she blew. He said he has his own software and programming that he could fine tune even better that the vec.

Jack B said:
Depending on the chamber size, you will could already be starting out with too high of a compression ratio, therefore, promoting detonation. I truly hope all is well with your engine.

A heads up in case you go with a head stud kit. You will have to clean out the bolt holes in the block. Do not use a tap, ARP has a thread cleaning tool.

Thanks Jack, I have decided to go with the arp head stud kit.

v10kingsnake · May 29, 2008

Joe @ JD's is a friggin madman when it comes to tuning anything using his SCT software. Since they now have SCT stuff for Vipers I 100% trust he can work miracles with the tune using it.

SYNFULL · Jun 2, 2008

Here is an update on my car-
Engine is apart and head gaskets are fine. Somehow the pressure lifted the heads up. I torqued them according to the manual- 35lbs first, then 90 lbs. Maybe they needed more with the s/c. I am having the valve seals replaced as I am told they are a much older inferior style that aren't used anymore and would not seal well. He showed me where one of the seals has moved and said i would be using a ton of oil if not replaced. I am also having the cc's of the cylinder checked to see if this was a possible contribution to the detonation. This is being done by the same shop that surfaced the heads originally and told me they only took off a few thousands of an inch. The heads will be ready tomorrow.
Thanks

Jack B · Jun 2, 2008

SYNFULL said:
Here is an update on my car-
Engine is apart and head gaskets are fine. Somehow the pressure lifted the heads up. I torqued them according to the manual- 35lbs first, then 90 lbs. Maybe they needed more with the s/c. I am having the valve seals replaced as I am told they are a much older inferior style that aren't used anymore and would not seal well. He showed me where one of the seals has moved and said i would be using a ton of oil if not replaced. I am also having the cc's of the cylinder checked to see if this was a possible contribution to the detonation. This is being done by the same shop that surfaced the heads originally and told me they only took off a few thousands of an inch. The heads will be ready tomorrow.
Thanks

Not that it was part of the issue, but, did they mill the intake side an equal amount

SYNFULL · Jun 3, 2008

Talked to the machine shop (Lorenzo's Fast Flow Cylinder Heads- Langhorn, Pa) today about my heads and there is a problem with them besides the crappy seals. A valve guide on each side of the head in the same spot is broken. One of the valves is very restricted in it's movement. He said I am lucky that I found this now as it would have been a very big problem. He also said this was probably done by whoever ported the heads as they usually tap the guides out when they are porting so they are out of the way and then tap them back in. I wonder if this could have caused the detonation?

Jack B said:
Not that it was part of the issue, but, did they mill the intake side an equal amount

I never thought to ask about that and I will check tomorrow.
Thanks

Jack B · Jun 4, 2008

If the guides caused an infiltration of oil it could have pushed the threshold a bit. Can you tell from the plugs which cylinders were an issue. Look for the pepper on the porcelain or damage to the strap or porcelain.

PowerKraus · Jun 4, 2008

You've receive a bit of good advice. The School of Hard Knocks has taught many a boosted students. At this point, you'll be best served posting up picks of the cylinders, head chambers, plugs, and valves. Dentonation, to the extent that 'lifts' a head, will leave great trace evidence. Also take some close ups of both head gaskets, and both sides. UNLESS you've already cleaned everything up...and thereby killed your own thread

plumcrazy · Jun 4, 2008

this is a great thread for future reference...thanx synful

SYNFULL · Jun 5, 2008

Picked up the heads today and he showed me where the 2 guides were broken. They were both on the same spot on each head. He said the guides were supposed to have C- clips in them and none of them did. He also showed me the teflon seals which he say's haven't been used in 10 years. They have been using Viton seals which perform much better. These heads were bought last summer from Roe.

V10TT · Jun 11, 2008

Roe Heads are done by Champion heads.. 260 cfm intake flow...

plumcrazy · Jun 11, 2008

i never heard anything good about the roe heads. guess this proves it

1TONY1 · Jun 11, 2008

SYNFULL said:
Picked up the heads today and he showed me where the 2 guides were broken. They were both on the same spot on each head. He said the guides were supposed to have C- clips in them and none of them did. He also showed me the teflon seals which he say's haven't been used in 10 years. They have been using Viton seals which perform much better. These heads were bought last summer from Roe.

Were the guides broken on the top side ? Have they checked for bent valves ?

Reference to your guy saying they have c-clips....maybe you need a new guy

Maybe someone changed all the guides ???

The expert says:

Vipers have a flanged guide, meaning the top of the guide is larger than the body of it so the guide cannot fall down into the port. They never came with retaining clips.
Teflon seals are not a good choice for a street engine. They oil.

SYNFULL · Jun 11, 2008

Tony,
He gave me the 2 broken guides but I don't know the top from the bottom

. It was broken off where the seal sits. I will post a picture when I get the car back because the parts are at the shop. I did look at the broken pieces for a spot where a clip could go and I didn't see any. I think he may have been mistaken on that one. He said all the valves and other parts checked out. He cc'd the heads and they were 75.4.

BTW Roe's site does state that they use the teflon seals and I did buy the heads second hand.
Thanks
Gary

1TONY1 said:
Were the guides broken on the top side ? Have they checked for bent valves ?

Reference to your guy saying they have c-clips....maybe you need a new guy
Maybe someone changed all the guides ???

The expert says:

Vipers have a flanged guide, meaning the top of the guide is larger than the body of it so the guide cannot fall down into the port. They never came with retaining clips.
Teflon seals are not a good choice for a street engine. They oil.

Canyon707 · Jun 11, 2008

mike & juli said:
I think that would actually be too depressing........Here's to getting yours SOON! ~juli

Juli twice???? I stop while I was ahead. :nono:

SYNFULL · Jun 14, 2008

Here is a shot of the broken valve guides. The mystery of why this all happened (coolant being pressurized and flying out while on the dyno) has come to light. It had nothing to do with detonation. It was an oversight on my amateur mechanical skills. When I installed the heads I didn't clean out the bolt holes. There was some coolant in them which prevented me from torquing them properly even though I cranked them up to 95 lbs. When we put the car on the dyno and ran the rpm's up the heads came up just enough to pressurize the coolant. I have the car back from the shop but they couldn't dyno tune it until next week so for the time being I am just taking it easy. If the heads didn't come off because of this mistake I would probably have chewed up the motor with a dropped valve.

BOTTLEFED · Jun 14, 2008

wow, sorry to hear about the reason for the failure,
but I guess it was better that it happened on the dyno than on the street, and fortunately there wasn't more damage

on the other hand(as has already been said), maybe this will help others in the future to not make the same mistake - too bad helping people in the future doesn't pay much

BTW, how can they tell there was coolant under the head bolts when you torqued them down?

SYNFULL · Jun 14, 2008

The mechanic drained all the coolant out from the block before he removed the heads. He noticed when the took the head bolts out there was coolant in the bolt holes and he knew it wasn't form his removal since all the coolant was already drained.

Good luck with your rebuild!

Car Took A Dump on the Dyno

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Viper Owner

Enthusiast

Enthusiast

Viper Owner

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Enthusiast

Similar threads

Forum statistics

Share this page