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  #11  
Old 09-29-2011, 06:34 PM
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Ms Grumpy Ms Grumpy is offline
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Originally Posted by PSYCHO6 View Post
Thank you for the explanation, now I know I need to watch and I hope you will soon present to guide me if I have other problems because you look good to know my engine I'm a little frenchie who does not know too the operation of the big block .... (at home more often you drive with 1.4 liter or 1.8litres engine of 90 to 150 horsepower ... lol
Doesn't matter where you are "frenchie". These guys know there stuff and it sounds like you are on your way to the motor and hp that you are looking for.
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  #12  
Old 10-06-2011, 03:13 PM
GDwrench GDwrench is offline
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Don't rule out the possibility of getting a "crate "engine. There is many choices of different power applications and price ranges also that can save time and headache of building an engine, especially if one is somewhat novice in mechanical ability ....I get a personal satisfaction from building my own, but there are times you wish it was as easy as hitting the "enter " key to purchase one! !
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  #13  
Old 10-06-2011, 03:58 PM
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Originally Posted by earthquake68 View Post
Another thing to keep in mind is horse power ratings. In 1972 they rated gross horse power. That is, they measured the horsepower at the flywheel. Since you lose horsepower through the drive train, the numbers were misleading. In 1973, they switched to a net rating. They actually measured horsepower off the back wheels. This gave a much more realistic rating, albeit a depressing one. A 350 horse power car in 1972 was only rated at at say 290 in 1973 with no changes to the combination.

Primarily what changed was compression ratio dropped and cam profiles changed. GM opened up the combustion chambers and dropped lift and duration on the cam. Since a 454 bore and stroke remain constant, a new set of pistons, heads and cam will start pumping horse power like a big dog. None of this is easy, but it's definitely doable.
I think the change was to measure HP with standard accessories attached, still at the flywheel. Standard accessories being alternator, exhaust manifolds, etc. Prior to that HP was measured off a basically bare engine. I may be wrong though, that's just what I recall.
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  #14  
Old 10-07-2011, 02:49 PM
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Originally Posted by GDwrench View Post
Don't rule out the possibility of getting a "crate "engine. There is many choices of different power applications and price ranges also that can save time and headache of building an engine, especially if one is somewhat novice in mechanical ability ....I get a personal satisfaction from building my own, but there are times you wish it was as easy as hitting the "enter " key to purchase one! !
GDwrench does have a good point. You could drop in a 454 HO or the ZZ454 and it is basically a modern version of what they would have come with. The best part is with HEI ignition and a hydraulic roller camshaft you won't have to do much in the line of maintenance also. It may be worth it.
http://paceperformance.com/i-6255291...te-engine.html
http://paceperformance.com/i-6255351...te-engine.html
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  #15  
Old 10-07-2011, 03:38 PM
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Originally Posted by Berg View Post
GDwrench does have a good point. You could drop in a 454 HO or the ZZ454 and it is basically a modern version of what they would have come with. The best part is with HEI ignition and a hydraulic roller camshaft you won't have to do much in the line of maintenance also. It may be worth it.
http://paceperformance.com/i-6255291...te-engine.html
http://paceperformance.com/i-6255351...te-engine.html
Right or wrong that's the direction I went when I replaced the 396 in our Chevelle. I opted for the 454 HO, there is a Chevy dealer, Rinke Chevrolet, that is one of the biggest sellers of Chevy crate engines anywhere. They have them stacked up in rows. Anyway they offered the best price so I picked one up. A 502 would have been nice but I wanted to stay with a mechanical fuel pump. I also needed the threaded boss for the 4 spd clutch Z-bar. Is it the best engine for the price? I don't know but it's a roller cam so no worries about wiping a cam because of low ZDDP levels. Had some oil burning issues, replaced the intake manifold gasket twice and pretty much cleaned that up.

Comes with essentially an Edlebrock RPM intake. Has the Chevy bowtie cast in it but looks identical to the RPM performer I had on the 396. Comes with flexplate, I had to replace that with a flywheel. Does not come with ignition, carb or other accessories but valve covers and all the other accessories from the 396 bolted right on. It does come with valve covers but I wanted to use the old chrome ones off the 396. I can't say it's the best engine available for the money but it runs on pump gas, has torque (500 ft lbs) that won't quit and runs good and strong. What's really nice is the torque starts right out of the gate and just continues through the RPM range.

There are other engines available for the same or less so you need to weigh all the factors. Just saying that it is an option and not necessarily a bad one.
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  #16  
Old 10-19-2011, 04:01 PM
PSYCHO6 PSYCHO6 is offline
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Hello everyone and thanks for your response, i have a question, what did you think of my engine soud? I think it isn't normal (air noise at the valve cover breather cap) pchiiiitt
http://www.youtube.com/watch?v=jUV1D...eature=related
http://www.youtube.com/watch?v=rhB-U...eature=related
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  #17  
Old 11-19-2011, 10:04 AM
PSYCHO6 PSYCHO6 is offline
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Hey guys, I have good news I think ... I just disassemble my rocker cover and I find probe industries 1.7 rockers and the number on my cylinder head is 353045. Do you think this is a good thing?
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  #18  
Old 11-19-2011, 04:21 PM
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Could that be 353049? That would be the original heads for that engine. If there are machine shops around you that work on those engines you could have larger valves installed, 2.19" intake, 1.88" exhaust versus the original 2.06" intake and 1.72" exhaust and have the combustion champers cleaned up. Those oval port heads will work well if the rest of the combination matches. You don't need rectangular port heads. Install a performance cam, moderate, nothing to radical. You can have the heads milled down or the block decked to increase compression but that isn't necessarily required. You can get over 400hp out of 8.5 to 9.0 compression if the rest of the parts match up. You also need to think about what octane rating gas is available there in France. I don't know but I suspect it's pretty low so you might not want a high compression engine. Put on an set of headers if you don't already have them. That's the best improvement for the price that you can make for that engine.

Have the ignition timing checked and see if you can get it up to around 16 to 18 degrees initial advance, that's after the other things are done. Big block Chevy engines like a lot of advance in the timing. You may also want to consider a little smaller carb. A 750 or 770 CFM carb with vacuum secondaries would work well on that engine. The 850 will work but it's more than your engine needs. Unless you have a ready supply of cheap gas, I doubt it, a smaller carb will work fine. Bigger isn't always better.

Not sure how easy it is to get all those things done in France. Here it's no problem at all. If you can't find an engine shop that knows something about Chevy big block engines, the crate engine as mentioned may be a better option since all the work will already be done. I know shipping and import taxes may be a lot. You have to weigh the 2 options, build your engine or buy a crate engine, and decide which is the best based on where you're located.
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  #19  
Old 11-20-2011, 02:43 PM
PSYCHO6 PSYCHO6 is offline
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thank you for your answers fast and accurate, but my heads are numbered 353045 cons I'm afraid my bridge bolt 10 does not take the shock ... What can I put as a bridge (adaptable)


in terms of gas here is 1.55 euros per liter approximately 2.10 dollars ...
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  #20  
Old 11-20-2011, 04:53 PM
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thank you for your answers fast and accurate, but my heads are numbered 353045 cons I'm afraid my bridge bolt 10 does not take the shock ... What can I put as a bridge (adaptable)


in terms of gas here is 1.55 euros per liter approximately 2.10 dollars ...
Sorry, can't find the 353045 casting number. 353049 are common and a decent head to work with. Can you ask the question again, I don't understand.

$2.10 per liter, around $8 a U.S. gallon, that's pretty expensive. Do they have different grades of gasoline there, different octane ratings. Do you know what the octane rating is?
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