150 Miles per Quart???
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Melting Slicks
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From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
Mine has Dart SHP. How long ago did you have the Dart height problem. Modern Darts have an excellent rep in my circle. As far as being an intake leak on the right side, remember they said all 8 plugs were black and oily!
The car is basically done unless the shop owners test runs reveal and issue. The plan is then for me to take it and rack up some miles to check for smoking and oil consumption! The only change so far has been to original baffled vc, tighten alt belt and replace clutch anti rattle springs.
When I get the car back it will only take a second to verify if the vc are unbaffled, I don't understand why you think they wouldnt divulge an intake leak
They have a very long and excellent rep, and an intake leak will not break them. There are a dozen guys in my club that use them though and they do know a slip up would be known to 20 vette owners overnite., if that is your point !
The car is basically done unless the shop owners test runs reveal and issue. The plan is then for me to take it and rack up some miles to check for smoking and oil consumption! The only change so far has been to original baffled vc, tighten alt belt and replace clutch anti rattle springs.
When I get the car back it will only take a second to verify if the vc are unbaffled, I don't understand why you think they wouldnt divulge an intake leak
They have a very long and excellent rep, and an intake leak will not break them. There are a dozen guys in my club that use them though and they do know a slip up would be known to 20 vette owners overnite., if that is your point !
Last edited by BPHORSEGUY; Jun 2, 2020 at 08:10 PM.
Le Mans Master
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From: Hermosa
About 8 years ago on the Dart SHPs for me. Dart generally does produce a good product, on my SHPs though I cannot say that I was impressed with them.
In your case the fact that a 180 cc SHP cc’s out to 192cc is going to help for that 383.
In your case the fact that a 180 cc SHP cc’s out to 192cc is going to help for that 383.
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Melting Slicks
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From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
Race Director
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From: South Western Ontario
It doesn't sound like there is any reason to be concerned yet. They likely want to give it a once over and make sure it's not something simple first before diving into it deeper.
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Melting Slicks
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From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
On the spec. sheet supplied by Dart it says 200cc!
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Melting Slicks
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From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
Le Mans Master
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From: Hermosa
Interesting. On the ATK site specs for that engine say it's a 180 cc head. So now ya gotta wonder which it is.
Spring surge on my heads was severe enough that the springs ate holes right through the steel shims underneath.
It's not too hard for them to pull a couple springs and take a look at least to see if the seals are dislodged.
https://www.high-performance-engines...5hp-p/hp94.htm
Spring surge on my heads was severe enough that the springs ate holes right through the steel shims underneath.
It's not too hard for them to pull a couple springs and take a look at least to see if the seals are dislodged.
https://www.high-performance-engines...5hp-p/hp94.htm
Last edited by REELAV8R; Jun 3, 2020 at 03:35 PM.
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Thread Starter
Melting Slicks
Joined: Jul 2010
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From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
Interesting. On the ATK site specs for that engine say it's a 180 cc head. So now ya gotta wonder which it is.
Spring surge on my heads was severe enough that the springs ate holes right through the steel shims underneath.
It's not too hard for them to pull a couple springs and take a look at least to see if the seals are dislodged.
https://www.high-performance-engines...5hp-p/hp94.htm
Spring surge on my heads was severe enough that the springs ate holes right through the steel shims underneath.
It's not too hard for them to pull a couple springs and take a look at least to see if the seals are dislodged.
https://www.high-performance-engines...5hp-p/hp94.htm
Edit: The engine has plenty of vacuum to run my Brakes, Headlights, and wiper so the cam can't be too hot !
Edit:
Ok I checked this morning it matches at 180
cc !
Last edited by BPHORSEGUY; Jun 4, 2020 at 08:22 AM.
Thread Starter
Melting Slicks
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From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
Ok.... so I talked to the shop at length this morning. Last week they ran the car up to redline in second gear and chopped the throttle and could make it smoke.... a lot. They then repeated with the ATK supplied valve covers and it smoked a lot less but still some. They then unplugged the PCVand no smoke at all
So that and the fact that the PCV was filled with oil I hope means it's not intake, valve seals or most importantly rings !
The plan next was to run some stock GM vc. I said you will need tall ones and he said that is the problem. All the vc have baffles but since they are taller for the roller rockers there is another 1 1/2" for oil to go under the baffles
I suggested 2 breathers but he did not want to eliminate the PCV
What about Chevy Performance vc $$$ ?
So that and the fact that the PCV was filled with oil I hope means it's not intake, valve seals or most importantly rings !
The plan next was to run some stock GM vc. I said you will need tall ones and he said that is the problem. All the vc have baffles but since they are taller for the roller rockers there is another 1 1/2" for oil to go under the baffles
I suggested 2 breathers but he did not want to eliminate the PCV
What about Chevy Performance vc $$$ ?
Le Mans Master
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From: Hermosa
Specs also say the rockers are stamped steel. Is a tall VC really necessary? There should be adequate room vs using aluminum roller rockers.
I’m using standard valve covers with full rollers. Steel not aluminum so they have a smaller profile.
I’m using standard valve covers with full rollers. Steel not aluminum so they have a smaller profile.
Thread Starter
Melting Slicks
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From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
So I called ATK
FIRST thing he asks is do you have a breather on the left valve cover, I answer yes. He says you need to run a line to the air cleaner like the stock setup
I explain I have the drop down, he says there should be a spot for a nipple
FIRST thing he asks is do you have a breather on the left valve cover, I answer yes. He says you need to run a line to the air cleaner like the stock setup
I explain I have the drop down, he says there should be a spot for a nipple
Le Mans Master
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From: Hermosa
going to the air cleaner just allows for the crank vapors to be drawn into the engine and burned during WOT conditions when it becomes a pressure vent. Due to the fact that at WOT conditions are intake vacuum is very low so the Pcv is not sucking much and crank case pressures are high form blow by. It overwhelms the Pcv so at that point the intake source on the left vc becomes a crankcase pressure vent.
Last edited by REELAV8R; Jun 4, 2020 at 03:54 PM.
Le Mans Master
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From: Unreconstructed, South Carolina
Maybe your 77 was an L82 with OE alum VC ... IF so, and IF BP installed stamped rockers ... re-install OE L82 VC
? question: if your choice ... what do You want to believe is the root cause ?
֎ still, intake
? question: if your choice ... what do You want to believe is the root cause ?
֎ still, intake
Thread Starter
Melting Slicks
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From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
Stock vc are short won't work. I just drove 40 highway miles with PCV disconnected and it still smoked so starting to it's not PCV or vc bafflilng
Maybe going back and asking them to pull intake
I cant explain all 8 plugs fouled if it's an intake leak on right side
Maybe going back and asking them to pull intake
I cant explain all 8 plugs fouled if it's an intake leak on right side
Last edited by BPHORSEGUY; Jun 4, 2020 at 10:14 PM.
Safety Car
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From: Fairfax Virginia
I remember when I first re-built my 427 and the mechanic buddy who built it with me told me not to go out on the highways and decelerate in gear as it puts undue stress on the piston rings and can screw up their sealing ability.
It was suggested to put it in neutral (or clutch in) while decelerating and only decelerate at low speeds while breaking it in for the first 500 miles. It might be because of the High compression I am using but he made a big deal about letting the rings get seated properly before going nuts on the engine.
It was suggested to put it in neutral (or clutch in) while decelerating and only decelerate at low speeds while breaking it in for the first 500 miles. It might be because of the High compression I am using but he made a big deal about letting the rings get seated properly before going nuts on the engine.
Le Mans Master
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From: Unreconstructed, South Carolina
OP BP
Don't have sos troubleshoot intake ... Take it to someone else that's Not a vette specialist. You need a new motor pro.
Ya know what folks are that keep on doing same thing but expect a different outcome, right ?...
... Dead or demented. No offense intended but perhaps curb some (if any) pilot 'tude-blindness
Seems you're less than 25 miles from Stafford speedway ... get ahold of someone there & find who are top 3 sbc race motor shops in area ... there 's probably dozens near you who're experts at this stuff.
There's was an honorable man name Bill Childs at nearby Somers CT ... not a racer but knows his sh7t ...also into planes... try & reach him for local refs.
Don't have sos troubleshoot intake ... Take it to someone else that's Not a vette specialist. You need a new motor pro.
Ya know what folks are that keep on doing same thing but expect a different outcome, right ?...
... Dead or demented. No offense intended but perhaps curb some (if any) pilot 'tude-blindness
Seems you're less than 25 miles from Stafford speedway ... get ahold of someone there & find who are top 3 sbc race motor shops in area ... there 's probably dozens near you who're experts at this stuff.
There's was an honorable man name Bill Childs at nearby Somers CT ... not a racer but knows his sh7t ...also into planes... try & reach him for local refs.
Thread Starter
Melting Slicks
Joined: Jul 2010
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From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
So I have now put about 70 miles mostly highway on the car, still smoking with PCV disconnected. The vc on.the right they have on there now doesn't even have a hole for the PVC ! So I think I can rule out the whole PVC baffling issue. Now onto the intake or valve seals, which is easier to check ? Do you need special equipment to do the valve seals in the car.
Also my oil pressure is about 40 psi at idle and 55 at 3500 rpm. That is about double what it was, with 10- 30 oil, same gage. Chevy says 10 psi per 1000 RPM min. I'm double that !
Also my oil pressure is about 40 psi at idle and 55 at 3500 rpm. That is about double what it was, with 10- 30 oil, same gage. Chevy says 10 psi per 1000 RPM min. I'm double that !
Last edited by BPHORSEGUY; Jun 7, 2020 at 07:52 PM.
Race Director
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From: Plano TX
The oil pressure is normal for a fresh engine, no worries there.
Intake gaskets are indeed the next thing to check. Have you had someone follow you and check when it smokes the worst? If it smokes the most under heavy load it points to rings. If it's the most under decel it's something in the heads/intake like intake gaskets, valve guides/seals etc.
Intake gaskets are indeed the next thing to check. Have you had someone follow you and check when it smokes the worst? If it smokes the most under heavy load it points to rings. If it's the most under decel it's something in the heads/intake like intake gaskets, valve guides/seals etc.