"I did post this on bp already"
I am thinking of rebuilding a spare 345 and tossing it into my truck. All I want is a close to stock engine built for durability and some extra performance but any easy mods that let it breather a hair easier or turn easier would be great.
But I can't find the FAQ's anymore explaining the difference between the emissions and non emissions engines. I have both available. So I'd like to know which one to rebuild for performance. I know there is a piston difference is that the only thing? I can't find any FAQ anywhere relating to it. I've tried searching.
Plans for it. I do plan on towing, off-roading and daily driving. I might do a dyno run or two and maybe a sprint down the drags on run what you bring night but not special. More just for the knowledge of what it has at that point then winning anything.
Current plans for actual rebuilt.
Basics first cleaning, checking for damage etc..
1. Any machining that is needed. (bore, hone deck block etc..)
2. Balancing the assembly
3. Rv style cam new lifters of course and push rods, rocker arms too.
4. Fuel injection
5. Glyptal coat the interior engine for better oil return. (I got to read more on the oiling thread to find out the areas to clean up too)
6. Gasket match heads and exhaust possibly intake too. I don't know if I'm comfortable enough to try to port my own heads.
7. Pistons unsure what to do here
8. Rods (just recondition them ?)
questions.
1 can I use a non emissions piston in an emissions engine to bump up compression? If I can how do I figure out the new compression and what is a safe ratio to stay at for regular pump gas which is 87 around here.
2. Are the heads different between a 345 non emissions or a 345 emissions. I need to be able to keep the emissions equipment on. But I do know I can put the air from the pump into the exhaust instead of into the exhaust ports at the heads. The emissions tech said as long as it gets into the exhaust before the cats. So if I can still mount the pump to an non emissions engine should I rebuild that one.
3. Should I use silvolite's cast pistons or deck for some forged pistons? The silvolites tech rep said the cast are good for 50-75 shot of nos or 8 lbs of boost if I keep the stock compression ratio of about 8.2 to 1. Not that I think I'd do either but it be nice to know I could if I want to.
4. Should I lighten the connecting rods?
5. Would porting the heads be really worth it. I'm not looking to make this thing scream just be better if I'm going to be in it anyways.
6. I've heard to go with bb Chevy springs but I have also heard not to.
7. What year did harden seats go into all 345s?
The reason I'm doing this is because I would like to know everything has been gone through incase I get transfer somewhere far away and need to drive it there. I'm hoping to stay in new england area though. It's easier to rebuild a spare then pull the current one. The current engine is running fine but it did have some nicked cam bearings a while back when we just slide a new cam in do to some flat lobes. I also had bent a push rod back then after replacing some lifters. The only thing it seems to be doing is pinging at a particular load but I think that is either a starving for fuel problem or a tuning problem which I'm hoping to fix this weekend. I might just have the distributor too far advance which I think is about 10 to 15 deg btdc right now.
Thanks and any advice is welcome except repowering with a non IH it's not my goal here. If I was going that route I'd be picking up a beater car or waiting for the current engine to die out then repower at that point.
Rich
current specs are 1979 Scout II 345 auto 3.07 gears with 31's
345's available are 1973 or newer.
I am thinking of rebuilding a spare 345 and tossing it into my truck. All I want is a close to stock engine built for durability and some extra performance but any easy mods that let it breather a hair easier or turn easier would be great.
But I can't find the FAQ's anymore explaining the difference between the emissions and non emissions engines. I have both available. So I'd like to know which one to rebuild for performance. I know there is a piston difference is that the only thing? I can't find any FAQ anywhere relating to it. I've tried searching.
Plans for it. I do plan on towing, off-roading and daily driving. I might do a dyno run or two and maybe a sprint down the drags on run what you bring night but not special. More just for the knowledge of what it has at that point then winning anything.
Current plans for actual rebuilt.
Basics first cleaning, checking for damage etc..
1. Any machining that is needed. (bore, hone deck block etc..)
2. Balancing the assembly
3. Rv style cam new lifters of course and push rods, rocker arms too.
4. Fuel injection
5. Glyptal coat the interior engine for better oil return. (I got to read more on the oiling thread to find out the areas to clean up too)
6. Gasket match heads and exhaust possibly intake too. I don't know if I'm comfortable enough to try to port my own heads.
7. Pistons unsure what to do here
8. Rods (just recondition them ?)
questions.
1 can I use a non emissions piston in an emissions engine to bump up compression? If I can how do I figure out the new compression and what is a safe ratio to stay at for regular pump gas which is 87 around here.
2. Are the heads different between a 345 non emissions or a 345 emissions. I need to be able to keep the emissions equipment on. But I do know I can put the air from the pump into the exhaust instead of into the exhaust ports at the heads. The emissions tech said as long as it gets into the exhaust before the cats. So if I can still mount the pump to an non emissions engine should I rebuild that one.
3. Should I use silvolite's cast pistons or deck for some forged pistons? The silvolites tech rep said the cast are good for 50-75 shot of nos or 8 lbs of boost if I keep the stock compression ratio of about 8.2 to 1. Not that I think I'd do either but it be nice to know I could if I want to.
4. Should I lighten the connecting rods?
5. Would porting the heads be really worth it. I'm not looking to make this thing scream just be better if I'm going to be in it anyways.
6. I've heard to go with bb Chevy springs but I have also heard not to.
7. What year did harden seats go into all 345s?
The reason I'm doing this is because I would like to know everything has been gone through incase I get transfer somewhere far away and need to drive it there. I'm hoping to stay in new england area though. It's easier to rebuild a spare then pull the current one. The current engine is running fine but it did have some nicked cam bearings a while back when we just slide a new cam in do to some flat lobes. I also had bent a push rod back then after replacing some lifters. The only thing it seems to be doing is pinging at a particular load but I think that is either a starving for fuel problem or a tuning problem which I'm hoping to fix this weekend. I might just have the distributor too far advance which I think is about 10 to 15 deg btdc right now.
Thanks and any advice is welcome except repowering with a non IH it's not my goal here. If I was going that route I'd be picking up a beater car or waiting for the current engine to die out then repower at that point.
Rich
current specs are 1979 Scout II 345 auto 3.07 gears with 31's
345's available are 1973 or newer.
