Will OverBoring Cause Overheating?
Will OverBoring Cause Overheating?
I have a 65 monza 110 and am wanting to just rebuild a good driver engine. I don't want a 60 over piston but was wandering if there is any 5 or 10 over pistons out there? I know Clarks has the 20 over. Also, If the bigger the over bore will there also be more heat problems in an overbored engine.
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Re: Will OverBoring Cause Overheating?
Making more power makes more heat. Overheating...not from an overbore alone for sure. I have had 30 over engines and 60 over engines no overheating issues with any of them
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/
Located in Snellville, Georgia
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/
Located in Snellville, Georgia
Re: Will OverBoring Cause Overheating?
What is the most common and best option of overbore size for a daily driver engine
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Re: Will OverBoring Cause Overheating?
Best option is the minimum it takes to get a round bore out of used jugs. It's a waste to bore straight to .060 if the jugs can be bored to .020 over. That way the next time it is rebuilt they can be bored to .040 and so on. If you plan on not reusing yours I don't think it really matters a whole lot. .060 overbore is not going to make a big difference.
Nate Wolfe
65 Corsa 180
61 Lakewood 140
65 Corsa 180
61 Lakewood 140
Re: Will OverBoring Cause Overheating?
What are your opinions on head rebuilding. What's the best things to do that will yield the greatest results?
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Re: Will OverBoring Cause Overheating?
That depends on the engine and how you plan on driving it. When I had a set of heads built for my car I had a lot of work done to them. They started out as 95hp heads which have similar compression ratio as the turbo heads but with a better chamber design. They had the quench area welded up to the gasket surface then machined flat. This gives more squish for better turbulence and less prone to detonation. They got 140 exhaust valves, cut down 140 intake valves, deep seats, intakes and exhausts ported, 140 exhaust tubes with the exhaust ports blended to match, bronze guides, heavier springs, titanium retainers, ceramic coated chambers, exhaust ports, and valves. Cc'd 8:1 compression. The ceramic coating is good for a turbo car to keep the heat in the exhaust. Heavier springs and titanium retainers will help out with a bigger cam and high rpm although I'm using a stock turbo cam. If you have a 110 or 140 I would say deep seats for peace of mind and porting would do you some good, especially the exhaust ports. If you intend on high rpm then you should upgrade the valve springs. The big valve conversions on small valve heads make a noticeable difference but if cost is a factor you may not want to go that route.
Nate Wolfe
65 Corsa 180
61 Lakewood 140
65 Corsa 180
61 Lakewood 140
Re: Will OverBoring Cause Overheating?
Ok I don't intend on doing high rpms but just want a solid driver. I see that Clarks has an Isky 270 cam is that the best all around cam as Clarks says for a daily driver? I also have found Isky 300 cams which look like way too much rpms? The Isky 260 is also interesting since they say it's a "low torque cam"? I would certainly like more torque in the low end.
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Re: Will OverBoring Cause Overheating?
I don't have a recommendation for you since I only have experience with the turbo engine. I'm sure others here do though. I have heard the 270 is a good cam for a driver though. 300 is likely too big unless you plan on racing your car. It all boils down to your intended use. Do you want more low end power or more high end power?
Nate Wolfe
65 Corsa 180
61 Lakewood 140
65 Corsa 180
61 Lakewood 140
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Re: Will OverBoring Cause Overheating?
With a 2 carb 110 engine don't go crazy with the cam. Close to stock or stock. Work your heads for tight quench and 9/9.5 compression. Rework your distributor advance curve and Lots of vacuum advance.
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Re: Will OverBoring Cause Overheating?
With a 2 carb 110 engine don't go crazy with the cam. Close to stock or stock. Work your heads for tight quench and 9/9.5 compression. Rework your distributor advance curve and Lots of vacuum advance. Also, I did not catch your transmission. It makes a difference.
Re: Will OverBoring Cause Overheating?
Also, if a 2 carb setup were not to work, what would be the difference between a 150 setup turbo and a 180 turbo setup? The engine is 164 cubic inch but is from 1964. I think that they didn't come out with 180 hp until 1965? Would a 180 work fine with this engine I have?
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