434ci, MMS 265 heads, Super Victor intake, MMS solid roller cam - dyno results
06-25-2019, 08:18 PM
#81
Of course there is a price to be paid in terms of consumables, etc. And apparently engine parts.I haven't done anything else yet. I should have a borescope by the weekend, so I plan to dive into it then. Unfortunately I have to do a good bit of disassembly to get into the area of the #8 cylinder (oil tank has to come out to get to that plug, and since I need to do it for other reasons, the header will also come out). So it will be a full day job assuming I don't melt in the Texas heat.
For those of you following along, let's say that I don't find any problems with the lifter, no scraps of aluminum in the valley, and I have a solid leakdown result. At that point I probably decide I'm going to put it back together and run it. But the question is:
Replace the one broken rocker with another YT, or replace the whole set with another brand/material/design?
I know which way I'm leaning, but input is always a good thing...
06-25-2019, 08:26 PM
#82
Me too... On both statements. And turns out it's the first that Tony knows of as well.
The car was running great! TOW is a handful on the track compared to the Porsches, BMWs, McLarens, Ferraris, etc that typically run the COTA HPDE events. I bested my previous best lap by over 5 seconds, and I still had a good bit more in me/her. I have some in-car video that I haven't had time to process yet, including at least one camera running when the rocker broke. I'll try to post it when I get it ready.
The car was running great! TOW is a handful on the track compared to the Porsches, BMWs, McLarens, Ferraris, etc that typically run the COTA HPDE events. I bested my previous best lap by over 5 seconds, and I still had a good bit more in me/her. I have some in-car video that I haven't had time to process yet, including at least one camera running when the rocker broke. I'll try to post it when I get it ready.
Man this wasnt the update I was wanting to see. Even the best parts break though, our twin turbo camaro is prime example of that. Hopefully its just a quick fix and your back at it again.
Congrats on the new best 5 seconds is huge!
06-25-2019, 08:59 PM
#83
ModSquad
iTrader: (6)
For anyone who's interested, I caught my fastest lap on video. Gives you an idea of how I use the car...
http://www.youtube.com/watch?v=IXrj2...ature=youtu.be
http://www.youtube.com/watch?v=IXrj2...ature=youtu.be
06-25-2019, 09:01 PM
#84
But the car performed great while it lasted. I had other gremlins that kept me from getting the most from the weekend, but they were simple fixes. I'll get her all fixed up and back out to COTA in the fall.And I'll probably come visit you again after I do whatever I end up doing here soon to make sure that she's still running the way she should. Thanx again for getting me in for a tuning session before my track weekend!
06-26-2019, 08:15 AM
#85
10 Second Club
I autocross as well as do the track days, but there is no comparison on the fun level. The 30 minute track sessions blow away the 45-60 second auto cross runs. Of course there is a price to be paid in terms of consumables, etc. And apparently engine parts.
I haven't done anything else yet. I should have a borescope by the weekend, so I plan to dive into it then. Unfortunately I have to do a good bit of disassembly to get into the area of the #8 cylinder (oil tank has to come out to get to that plug, and since I need to do it for other reasons, the header will also come out). So it will be a full day job assuming I don't melt in the Texas heat.
For those of you following along, let's say that I don't find any problems with the lifter, no scraps of aluminum in the valley, and I have a solid leakdown result. At that point I probably decide I'm going to put it back together and run it. But the question is:
Replace the one broken rocker with another YT, or replace the whole set with another brand/material/design?
I know which way I'm leaning, but input is always a good thing...
Of course there is a price to be paid in terms of consumables, etc. And apparently engine parts.I haven't done anything else yet. I should have a borescope by the weekend, so I plan to dive into it then. Unfortunately I have to do a good bit of disassembly to get into the area of the #8 cylinder (oil tank has to come out to get to that plug, and since I need to do it for other reasons, the header will also come out). So it will be a full day job assuming I don't melt in the Texas heat.
For those of you following along, let's say that I don't find any problems with the lifter, no scraps of aluminum in the valley, and I have a solid leakdown result. At that point I probably decide I'm going to put it back together and run it. But the question is:
Replace the one broken rocker with another YT, or replace the whole set with another brand/material/design?
I know which way I'm leaning, but input is always a good thing...
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Darth_V8r (06-28-2019)
06-26-2019, 09:08 AM
#86
I think lazerlemonta gave some solid advice. Look for early signs that this is a failure pattern based on design/parts/use incompatibility and not just a single faulty part (bad casting?) As said, sometimes even the best parts break (ask me how I know). It would be a shame to replace 14 perfectly good rockers if it weren't necessary but I can also understand not wanting a repeat occurance with potentially worse results.
I am no engineer and didn't even stay at a Holiday Inn Express last night, but I would be curious about the break pattern in your picture. The one side of the break looks as I would expect of a cast piece that snaps. It's kinda "granular" for a lack of a better term. But the other side looks smoother and had those linear tiers. Again, I dont know what any of this means in terms of why or how it broke. Really just an observation but I'd be interested if anyone had a professional opinion.
I am no engineer and didn't even stay at a Holiday Inn Express last night, but I would be curious about the break pattern in your picture. The one side of the break looks as I would expect of a cast piece that snaps. It's kinda "granular" for a lack of a better term. But the other side looks smoother and had those linear tiers. Again, I dont know what any of this means in terms of why or how it broke. Really just an observation but I'd be interested if anyone had a professional opinion.
06-26-2019, 11:05 AM
#87
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You can't always see stress cracks, but a simple die penetrant kit will reveal them. Like the suggestion to have a few spar pairs in the car also. Great advice!
06-27-2019, 05:00 PM
#88
Well, it wasn't the end of the weekend I had hoped for either. But the car performed great while it lasted. I had other gremlins that kept me from getting the most from the weekend, but they were simple fixes. I'll get her all fixed up and back out to COTA in the fall.
And I'll probably come visit you again after I do whatever I end up doing here soon to make sure that she's still running the way she should. Thanx again for getting me in for a tuning session before my track weekend!
But the car performed great while it lasted. I had other gremlins that kept me from getting the most from the weekend, but they were simple fixes. I'll get her all fixed up and back out to COTA in the fall.And I'll probably come visit you again after I do whatever I end up doing here soon to make sure that she's still running the way she should. Thanx again for getting me in for a tuning session before my track weekend!
Not a problem, its always a pleasure tuning a car like yours. Did you drive it enough to notice if they changes we made helped the fuel mileage any?
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Che70velle (06-28-2019)