I had one question in general about these imports. Is there anything I need to make sure to do to the bottom end of my 200 since i am going to make the top end so strong? You know the machining, FSPP 268 cam, Holley or Webber carb(maybe a four barrel if at all possible),FSPP head building packages(dual timing chain, roller tip rockers,Hyd liftersClevite 77's, molly pushrods,port flow valves teflon valve seals, dual pacemaker headers etc.) A couple of mechanics question me about that whenever I explain what I want to do with my six cylinder. I don't know if it's me missing some info or just them being eight cylinder-minded. They both brought up bottom end strength and balancing as issues. Are they just trying to make up things to charge me more money with? I was under the impression that a short block should be balanced anyway, but what else should be done to my bottom end before adding the high performance stuff with an Aussie or Argie Head? What would you go with if you had the money to buy either?
Bottom end of an Aussie or Argie head build up??
- Thread starter bdj66
- Start date
I'd go with a new cam and lifters, pushrods and roller rockers. on the bottom end use arp rod bolts will help with adding strength. how much do you want to spend?
If your mechanics are laughing at you (like i am sure mine were) go somewhere else. I found a good mechanic who was happy to help me fix the problems the first guy screwed up. now i am plannig a forced air (trubo or supercharger) and Phil( the second mechanic) will be the one to do it. so make sure you find a good mechanic first!!!
Good luck
John
If your mechanics are laughing at you (like i am sure mine were) go somewhere else. I found a good mechanic who was happy to help me fix the problems the first guy screwed up. now i am plannig a forced air (trubo or supercharger) and Phil( the second mechanic) will be the one to do it. so make sure you find a good mechanic first!!!
Good luck
John
No, the bottom end is over designed as it is. If good forged conrods, HSC pistons and a good cam and oil pump and bearings, there is little to go wrong. Harmonic balancers are a weak point, and don't overbore unless you have a spare block.
Timing gears are hard on chains. Until we figure out how to get better chains, you'll find the chain life is short, and a strong engine will slowly loose power over the first few years as the chain stretches.
Timing gears are hard on chains. Until we figure out how to get better chains, you'll find the chain life is short, and a strong engine will slowly loose power over the first few years as the chain stretches.
xtaxi -
What do you mean by harmonic balancers being a weak point? Should I get a high performance one like the one from FSPP. Will the dual chain do me any good? What would you consider over bore because I don't have a spare block? Thanks, still waiting to see those pictures of those cars with a 7 1/4 rear end you were talking about on my other thread.
ruckus68-
Everything you mentioned I was planning on using, get out of my head. I am still trying to decide on a mechanic and your right if they aint feeling it i don't want them. Thanks
Any one else have any opinions on this?
What do you mean by harmonic balancers being a weak point? Should I get a high performance one like the one from FSPP. Will the dual chain do me any good? What would you consider over bore because I don't have a spare block? Thanks, still waiting to see those pictures of those cars with a 7 1/4 rear end you were talking about on my other thread.
ruckus68-
Everything you mentioned I was planning on using, get out of my head. I am still trying to decide on a mechanic and your right if they aint feeling it i don't want them. Thanks
Any one else have any opinions on this?
The front pulley takes a lot of vibration out of the cast iron crank. The elastomeric material tends to break, so you need to get a good stock one, and check its condition.
It's a problem only if you are giving it some wicked tratment, and it breaks at 5 grand.
The blocks don't like the really big overbores.
Use the bare minimum to true up the bore to take an avaliable piston. If you can get away with 20 thou, do so. If it needs 30 0r 40 thou, well go do it, but anything over 30 is more risky. Run into a weak point, and the engine can develope a classic case of block porosity. There are sonar ray checks, full pressure checks using fast flowing crack finding kerosene/parafin to trace weak areas, but there is no guarantee that the block will remain crack free in the 40, 56, 60 thou overbore zone.
I've done a 56 thou clean up (to a stock Chev 305 piston size) on my Aussie block, but it has little core shift, and lots of metal. On the short deck 200's, they aren't quite as thick and have been made with metal saved in the water jacket. A thin wall engine is just that...a thin wall engine. Stock, you won't see much more than 180 thou of cast iron around each side of the 3.68" bore. Take it out to 60 thou, and you have less 150 thou of thickness of metal, less the rusted out section from ~ 30 years of water circulating. As the Schendahls and others have said here, the color of the cast iron changes, and the machinist can feel differences in the quality of the bore as you go deaper into the overbore.
As for the diff, heres the info!
It's a problem only if you are giving it some wicked tratment, and it breaks at 5 grand.
The blocks don't like the really big overbores.
Use the bare minimum to true up the bore to take an avaliable piston. If you can get away with 20 thou, do so. If it needs 30 0r 40 thou, well go do it, but anything over 30 is more risky. Run into a weak point, and the engine can develope a classic case of block porosity. There are sonar ray checks, full pressure checks using fast flowing crack finding kerosene/parafin to trace weak areas, but there is no guarantee that the block will remain crack free in the 40, 56, 60 thou overbore zone.
I've done a 56 thou clean up (to a stock Chev 305 piston size) on my Aussie block, but it has little core shift, and lots of metal. On the short deck 200's, they aren't quite as thick and have been made with metal saved in the water jacket. A thin wall engine is just that...a thin wall engine. Stock, you won't see much more than 180 thou of cast iron around each side of the 3.68" bore. Take it out to 60 thou, and you have less 150 thou of thickness of metal, less the rusted out section from ~ 30 years of water circulating. As the Schendahls and others have said here, the color of the cast iron changes, and the machinist can feel differences in the quality of the bore as you go deaper into the overbore.
As for the diff, heres the info!
A
Anonymous
Guest
For a super strong bottom end only a few things are required,
1.) balance entire assy (crank, rods, pistons, etc)
2.) Install ARP rod bolts.
3.) FSPP double roller timing chain & gears
Then if you want to make it indestructable,
4.) FSPP "Hi-Po" balancer
5.) ARP main studs.
6.) FSPP forged pistons
Thats all you need to do!
Later,
Doug
1.) balance entire assy (crank, rods, pistons, etc)
2.) Install ARP rod bolts.
3.) FSPP double roller timing chain & gears
Then if you want to make it indestructable,
4.) FSPP "Hi-Po" balancer
5.) ARP main studs.
6.) FSPP forged pistons
Thats all you need to do!
Later,
Doug
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