rochester carb info

[Larry E.]

Re: rockchester carb info

Steve------


I can absolutely guarantee you that no 1970 Corvette except LT-1 was equipped with AIR ("smog pump"). So, you can be absolutely assured that the judges got it wrong on this point.

Some folks might "extrapolate" that since all 1969 Corvettes were originally equipped with AIR (and they were), that 1970 must be the same. It's not, though. For 1970 all engines except LT-1 used CCS (controlled combustion system) for exhaust emissions control. The same system was used for most 1968-69 Chevrolets with automatic transmission EXCEPT Corvette.

Joe: Just curious; would not the 1970 TCS system also play into fact of no AIR ("smog pump")?? Larry

[Michael W.]

Re: rockchester carb info

Joe: Just curious; would not the 1970 TCS system also play into fact of no AIR ("smog pump")?? Larry

The two systems are completely independent in function. Depending on the year or model it's possible to have one, the other or both.

[Joe L.]

Re: rockchester carb info

The two systems are completely independent in function. Depending on the year or model it's possible to have one, the other or both.

Mike and Larry------


Yes, for example 1970 LT-1 had both AIR and TCS. However, I'm not so sure that TCS and CCS are completely independent of each other. Part of the required exhaust emissions control might have been accomplished by the TCS system. Certainly, not all of it, though.

[David P.]

Re: rockchester carb info

Joe, thanks for the info. I will start a thread on this at some point...

David------


Yes, it has been reported that some earlier 1970 with LS-5 did have AIR-type exhaust manifolds with plugged fittings. However, I believe that these were plugged with an internal, square drive pipe plug. These are uncommon in the thread size required. If yours have internal, hex drive or external square drive, that would make me suspicious that they're not original to the car.

[Joe L.]

Re: rockchester carb info

Joe, thanks for the info. I will start a thread on this at some point...

Dave------


What is the configuration of the AIR fitting plugs on your driver side manifold?

[David P.]

Re: rockchester carb info

20140105_180736.jpgJerry iphone 112713 114.jpg
Steve,
It's very rare to find another unmolested Cortez Silver 1970 454. 58K original miles and unrestored. I have original paint on the door jambs, but the exterior is wearing a circa 1995 repaint. I have heard that the original silver paint aged very quickly and did not wear well. I'd love to see some pics of your original silver.

thanks all, that means I can spend the money saved from not requiring the smog components on other items. The cars birth date is may 17th 1970 and has only just done 34.000 original miles and is a no hit unmolested vehicle that after 44 years only requires some cleaning of the chassis and engine bay and a body paint where the silver has fadded in the sun. I have looked at the exhaust manifolds and the casting dates are correct and they have no plugged holes for the A.I.R hoses. the car is numbers matching.

[David P.]

Re: rockchester carb info

Joe, let me shoot a pic when I get home. I believe they are square drive pipe plug-type.

[David P.]

Re: rockchester carb info

20140123_175905.jpg
Steve and Joe, here is what my March 9 #5864 car passenger side manifold looks like. Casting # is 3880828. TIM says 1970 LS5s between 6000 and 8000 may have this config. Here's at least one example for serial # less than 6000 with AIR holes/plugs on the passenger side. Time to start this as a new thread...
Joe, did you mention what is your serial?

I was in error previously stating the AIR holes were on the driver side. Driver side has no such holes, which appears correct per the TIM.

Off topic, but is there an active effort underway to compose the next 5th edition 70-72 TIM???

[Terry M.]

Re: rockchester carb info

[ATTACH=CONFIG]50403[/ATTACH]
Steve and Joe, here is what my March 9 #5864 car passenger side manifold looks like. Casting # is 3880828. TIM says 1970 LS5s between 6000 and 8000 may have this config. Here's at least one example for serial # less than 6000 with AIR holes/plugs on the passenger side. Time to start this as a new thread...
Joe, did you mention what is your serial?

I was in error previously stating the AIR holes were on the driver side. Driver side has no such holes, which appears correct per the TIM.

Off topic, but is there an active effort underway to compose the next 5th edition 70-72 TIM???

Define what you mean by "active effort."

[David P.]

Re: rockchester carb info

Define what you mean by "active effort."

Fair enough I guess I mean active enough to result in publication within the next 6-9 months.

[Joe L.]

Re: rockchester carb info

[ATTACH=CONFIG]50403[/ATTACH]
Steve and Joe, here is what my March 9 #5864 car passenger side manifold looks like. Casting # is 3880828. TIM says 1970 LS5s between 6000 and 8000 may have this config. Here's at least one example for serial # less than 6000 with AIR holes/plugs on the passenger side. Time to start this as a new thread...
Joe, did you mention what is your serial?

I was in error previously stating the AIR holes were on the driver side. Driver side has no such holes, which appears correct per the TIM.

Off topic, but is there an active effort underway to compose the next 5th edition 70-72 TIM???

Dave------


These appear to be the plugs I would expect for an original configuration.

[Terry M.]

Re: rockchester carb info

Fair enough I guess I mean active enough to result in publication within the next 6-9 months.

Given that definition the answer is no. Most, maybe all, JM revision teams are always on the lookout for needed update and changes and additions. From the time the National Judging Chairman says "GO' it is likely to take one to one and one half years to get a manual to print.

[David P.]

Re: rockchester carb info

Thank you for the feedback Joe.

Dave------


These appear to be the plugs I would expect for an original configuration.

[David P.]

Re: rockchester carb info

OK, thanks Terry. Appologies to the OP for hijacking his thread, but Steve may likely run across anomolies in the TIM that need to be fed back to the revision team as well, given the original-sounding nature of his '70. I have a couple discrepancies with the 4th edition TIM (like my AIR-plugged manifold outside the 6000-8000 serial range) that I'll keep in my pocket in anticipation of the formation of a TIM revision team and any information requests they may make.

Dave

Given that definition the answer is no. Most, maybe all, JM revision teams are always on the lookout for needed update and changes and additions. From the time the National Judging Chairman says "GO' it is likely to take one to one and one half years to get a manual to print.

[Terry M.]

Re: rockchester carb info

OK, thanks Terry. Appologies to the OP for hijacking his thread, but Steve may likely run across anomolies in the TIM that need to be fed back to the revision team as well, given the original-sounding nature of his '70. I have a couple discrepancies with the 4th edition TIM (like my AIR-plugged manifold outside the 6000-8000 serial range) that I'll keep in my pocket in anticipation of the formation of a TIM revision team and any information requests they may make.

Dave

That JM Revision team has been in place for several years.

We are happy to monitor and receive what additional information you generate, however, when we cite a serial number range for changes in the TIM&JG all of those numbers are based on examples we have seen to the point of the JM printing. They are all always approximate, and it would be a mistake to assUme that all BB engines up to a given point had no AIR ports and again at another point changed back. The exhaust manifolds were installed at the engine plant. The engines were installed in Corvettes in no particular order, so there may and probably are gaps in this feature. Good luck with you search. We ill be watching.