Engine rebuild advice
Thread Starter
Race Director
Joined: Jun 2004
Posts: 13,956
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From: WI
Greg, I stopped in at my builders and snapped a few pictures of the pistons. You were interested in what they looked like. He said the more expensive version ($75ish more) has the valve reliefs cut out and radiused better instead of forged in.
Pistons IC9930-30 $322.99
Forged, Flat, 4.030 in. Bore, 5/64 in., 5/64 in., 3/16 in. Ring.
Weight Piston / Pin: 478 / 132
(3.7cc valve relief)
This new line features VMS 75 alloy, true arc-style lock rings, broached pin holes, breakthrough oil returns, and 5/64 in. ring packs--all designed to be easy on your wallet! In addition, most flat-top and dish applications are available in an offset pin design, which will help to quiet those street motors.
We got talking about how far in the hole they would be and I asked how the stock engine looked that way. He said they were all over the place and that's pretty normal. My stock pistons were in the hole, 13, 16, 23, 26, etc. These will all be at 5. My bob weight is 1856 g. Stock was something like 1910 g.
Pistons IC9930-30 $322.99
Forged, Flat, 4.030 in. Bore, 5/64 in., 5/64 in., 3/16 in. Ring.
Weight Piston / Pin: 478 / 132
(3.7cc valve relief)
This new line features VMS 75 alloy, true arc-style lock rings, broached pin holes, breakthrough oil returns, and 5/64 in. ring packs--all designed to be easy on your wallet! In addition, most flat-top and dish applications are available in an offset pin design, which will help to quiet those street motors.
We got talking about how far in the hole they would be and I asked how the stock engine looked that way. He said they were all over the place and that's pretty normal. My stock pistons were in the hole, 13, 16, 23, 26, etc. These will all be at 5. My bob weight is 1856 g. Stock was something like 1910 g.
Last edited by Aardwolf; Sep 24, 2010 at 03:26 PM.
Thread Starter
Race Director
Joined: Jun 2004
Posts: 13,956
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From: WI
Looks like I will be 10.67 static and 8.22 dynamic with the Pat Kelly calc. He worked on my heads and increased them to 61 cc. With a .41 gasket my quench will be .46 though I could use a special gasket for less.
Race Director
Joined: Nov 2003
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
You'll find some who will say to get quench under that .040" mark. More say under .050" is "good". Assuming clearance isn't an issue, I think .005" thinner gasket would be good -- if you can use one. If not, don't worry about it.
I would, however, take the time to radius the edges on those pistons. Won't hurt, might help! They look good too, BTW!
Even though your static is higher than some builders would like, your DCR looks perfect.
Still a 355, right?
I would, however, take the time to radius the edges on those pistons. Won't hurt, might help! They look good too, BTW!
Even though your static is higher than some builders would like, your DCR looks perfect.
Still a 355, right?
Thread Starter
Race Director
Joined: Jun 2004
Posts: 13,956
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From: WI
Yes, it's a 355. The compression changed a little! The advertised cam specs were different than what it actually was on the cam docker. 10.65 static compression, 8.429 dynamic (2° timing chain stretch = 8.29). The hot cam is installed at 109, he thought a timing chain would stretch 1 to 2° when I asked him about it.
This is my bill:
It looks like if you reused more parts you could keep a 355 bill to $1000 and a 383 to $1500.
I made some progress with it:
This is my bill:
It looks like if you reused more parts you could keep a 355 bill to $1000 and a 383 to $1500.
I made some progress with it:
Last edited by Aardwolf; Sep 24, 2010 at 03:26 PM.
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Le Mans Master
Joined: Oct 2007
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From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
2024 C5 of the Year Winner - Modified
2023 C5 of the Year Finalist - Modified
2022 C5 of the Year Finalist - Modified
St. Jude Donor '09-'10-'11
This is looking good Andrew! Are you still going to be in TTB with that engine? What tires will you be using?
Thread Starter
Race Director
Joined: Jun 2004
Posts: 13,956
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From: WI
I'm not sure! NASA chose not to have a Road America event so I'm not attending any. Maybe next year! There was a lot of excuses on their forum about Road America offering them poor event dates. But GT Track days as a brand new club got a summer date just fine. Tires, I have a stack of V710 scrubs to use up this summer.
The MR really did find a home, I'm not switching any more intakes!
The MR really did find a home, I'm not switching any more intakes!
Thread Starter
Race Director
Joined: Jun 2004
Posts: 13,956
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From: WI
It's really nice to work on. I'd like to start it up but have been sidetracked on a bunch of other projects.
I made a heater core box, since I gotta have my comforts!
I made the C-beam super easy with access plates.
I remounted the stock cluster with a custom bracket to the wave shaped piece of metal spanning the cabin.
The ratchet shifter with paddle shift like control is almost done.
Brake ducts have to be painted yet and installed.
I have to finish the power steering mods yet and the fuel line with a new fuel filter location.
I made a heater core box, since I gotta have my comforts!
I made the C-beam super easy with access plates.
I remounted the stock cluster with a custom bracket to the wave shaped piece of metal spanning the cabin.
The ratchet shifter with paddle shift like control is almost done.
Brake ducts have to be painted yet and installed.
I have to finish the power steering mods yet and the fuel line with a new fuel filter location.
Last edited by Aardwolf; Sep 24, 2010 at 03:29 PM.
Le Mans Master
Joined: Oct 2007
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From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
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2023 C5 of the Year Finalist - Modified
2022 C5 of the Year Finalist - Modified
St. Jude Donor '09-'10-'11
Wow! You have been busy! Looks really good. Id like to see how those ducts look bolted up when you get them on. Does the air blow at the center of the rotor or the face?
Thread Starter
Race Director
Joined: Jun 2004
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From: WI
I did some limited running of the rebuild. It turned out nice!
I did take some pictures of the ducts, I suppose I should make a thread for that.
I did take some pictures of the ducts, I suppose I should make a thread for that.
Last edited by Aardwolf; Sep 24, 2010 at 03:30 PM.
Le Mans Master
Joined: Oct 2007
Posts: 9,682
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From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
2024 C5 of the Year Winner - Modified
2023 C5 of the Year Finalist - Modified
2022 C5 of the Year Finalist - Modified
St. Jude Donor '09-'10-'11
Lookin good Andrew! 
Did you paint the valve covers or were they just that dark from the factory? I remember mine being more silver.
Did you paint the valve covers or were they just that dark from the factory? I remember mine being more silver.
Thread Starter
Race Director
Joined: Jun 2004
Posts: 13,956
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From: WI
This combo has been very nice! The MR revs so fast it's ridiculous. I've been impressed with the low end torque. For what this cost I've been very happy. 12.3 et at 112 mph last night. I had the rev limit set to low and to much gas. 1.85 60 foot.
Race Director
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good job. motor looks very clean, and thats one light car.
Thread Starter
Race Director
Joined: Jun 2004
Posts: 13,956
Likes: 706
From: WI
Thanks Rick! I had it out at Road America two weeks ago and did well with all the ZO6's. I got behind a newer one that just barely pulled on me in the straights but my car was much better in braking and the corners. A ZR1 was there and in a whole nother league.
Some vid short shifting:
Wish the stock radiator was a little better at RA. Cruising last night it was at 165° but gets a little hot on the open track.
Some vid short shifting:
Wish the stock radiator was a little better at RA. Cruising last night it was at 165° but gets a little hot on the open track.