Race car dyno video, and invitiation to our first race this season
#32
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Yow, total bummer. And brand-new looking chain tensioner pads- Wonder whether there would be any interpretable tell-tales in terms of wear on one pad or the other on this side of the motor vs. the other.
Maybe there's an IWIS racing chain that would be more robust (or at least provide theoretical peace of mind)?
Maybe there's an IWIS racing chain that would be more robust (or at least provide theoretical peace of mind)?
#33
Rennlist Member
Yow, total bummer. And brand-new looking chain tensioner pads- Wonder whether there would be any interpretable tell-tales in terms of wear on one pad or the other on this side of the motor vs. the other.
Maybe there's an IWIS racing chain that would be more robust (or at least provide theoretical peace of mind)?
Maybe there's an IWIS racing chain that would be more robust (or at least provide theoretical peace of mind)?
Sorry to hear Carl!!! Darn, right after qualifying!! UGGGGGg
any video footage????
#34
Developer
Thread Starter
Still looking for the causal point - haven't figured that out yet.
Exhaust cam has 1 broken tooth, the chain tensioner is torn out of the head, the chain is broken. That's just what I can see. Tomorrow I will do a cylinder leak-down test to see if I have bent valves or not.
Mid-Ohio is 30 days away...
Exhaust cam has 1 broken tooth, the chain tensioner is torn out of the head, the chain is broken. That's just what I can see. Tomorrow I will do a cylinder leak-down test to see if I have bent valves or not.
Mid-Ohio is 30 days away...
#35
Rennlist Member
that's ugly!
the broken tooth is probably in the pan right now. are you going to change the cam? I used the three cams with one tooth missing each for a while. as soon as there were two teeth missing adjacent, I pulled the cams. I think my problem was due to the chain being worn out and loose. as well as the tensioner being jammed.
the broken tooth is probably in the pan right now. are you going to change the cam? I used the three cams with one tooth missing each for a while. as soon as there were two teeth missing adjacent, I pulled the cams. I think my problem was due to the chain being worn out and loose. as well as the tensioner being jammed.
#36
Developer
Thread Starter
I wondered if you could run a cam with one tooth missing.... but I wont do it. I have cores, so I am sending off to have a replacement made now. I have a pair of the 951 IWIS racing chains on their way to me now - thanks to Adam Birnbaum. Thanks Adam!
Last edited by Carl Fausett; 04-28-2015 at 04:21 PM.
#37
Developer
Thread Starter
Some good news: every cylinder in that bank passed a cylinder-leak-down test at only 7% leakage. That, and the fact we could see no impacts with the bore scope, lead us to think we escaped without any bent valves.
The distributor drive collar is cracked in two places. Wow. That cam stopped abruptly when the chain piled up!
The intake cam is undamaged, and I even found the tooth! Can't believe I found the tooth.
Here are some pics:
The distributor drive collar is cracked in two places. Wow. That cam stopped abruptly when the chain piled up!
The intake cam is undamaged, and I even found the tooth! Can't believe I found the tooth.
Here are some pics:
#38
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A little JB Weld, she'll be good as new
#39
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I've seen sprockets repaired with the right TIG technique and some local heat-treating. The load on an individual tooth isn't that great, and if the rollers in the chain actually roll and the chain isn't stretched, a good repair will last as long as the rest of the sprocket. Just don't warp the cam...
Good that you have spares available. Hate to lose a chain at 220 on the salt. It would ruin your day.
Good that you have spares available. Hate to lose a chain at 220 on the salt. It would ruin your day.
#40
Rennlist Member
I've seen sprockets repaired with the right TIG technique and some local heat-treating. The load on an individual tooth isn't that great, and if the rollers in the chain actually roll and the chain isn't stretched, a good repair will last as long as the rest of the sprocket. Just don't warp the cam...
Good that you have spares available. Hate to lose a chain at 220 on the salt. It would ruin your day.
Good that you have spares available. Hate to lose a chain at 220 on the salt. It would ruin your day.
#41
Rennlist Member
how were the lap times and do you have some video of qualifying??
I found your times on the nasa site. looks like the track is very close to the times that are run at LAGUNA. (top GTS3 cars are in the 1:36-7s)
http://www.nasamidwest.com/results/?...ventID=1129553
I found your times on the nasa site. looks like the track is very close to the times that are run at LAGUNA. (top GTS3 cars are in the 1:36-7s)
http://www.nasamidwest.com/results/?...ventID=1129553
#42
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This looks great! What NASA sanction are you running in?
-Luccia
-Luccia
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#43
Developer
Thread Starter
I am in NASA Midwest, the GTS series, Unlimited group. So: GTS-U
Mark: I was paying no attention to my lap times whatsoever. Like I said, I had a new differential that I needed to learn with aftermarket ramps and clutches, a new transmission, a new motor that I was still breaking in, and 3-year-old slicks (hard) on a track that had puddles and rivulets across it.
Nope, just trying to get some seat time and sort out the car.
Mark: I was paying no attention to my lap times whatsoever. Like I said, I had a new differential that I needed to learn with aftermarket ramps and clutches, a new transmission, a new motor that I was still breaking in, and 3-year-old slicks (hard) on a track that had puddles and rivulets across it.
Nope, just trying to get some seat time and sort out the car.
#44
Rennlist Member
I am in NASA Midwest, the GTS series, Unlimited group. So: GTS-U
Mark: I was paying no attention to my lap times whatsoever. Like I said, I had a new differential that I needed to learn with aftermarket ramps and clutches, a new transmission, a new motor that I was still breaking in, and 3-year-old slicks (hard) on a track that had puddles and rivulets across it.
Nope, just trying to get some seat time and sort out the car.
Mark: I was paying no attention to my lap times whatsoever. Like I said, I had a new differential that I needed to learn with aftermarket ramps and clutches, a new transmission, a new motor that I was still breaking in, and 3-year-old slicks (hard) on a track that had puddles and rivulets across it.
Nope, just trying to get some seat time and sort out the car.
we want to know how fast down the main straight.
#45
Developer
Thread Starter
I have found a supplier of the IWIS racing camshaft chains, a direct replacement that is heavier and stronger just for performance/racing motors. These were invented because Porsche was experiencing cam chain failures on the 951 (944 Turbo) after they installed stronger valve springs to control the boost. Sound familiar?
If you have high-lift cams or high-strength valve springs, please consider these cheap insurance against a potentially very expensive repair.
I've just put a pair in, and I offer them to you now as well:
http://www.928motorsports.com/parts/...aft_chains.php
If you have high-lift cams or high-strength valve springs, please consider these cheap insurance against a potentially very expensive repair.
I've just put a pair in, and I offer them to you now as well:
http://www.928motorsports.com/parts/...aft_chains.php