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Old 03-07-2014, 12:40 PM   #1
Hugh Mongus
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Engine rebuild info

I am getting my engine rebuilt by a local shop. The rebuild is going to cost me $900. The mechanic said I could buy, and bring him, the cam I want to use with the engine and he will install it at no extra charge. I just ordered the Lunati 10602 kit that includes lifters, springs, retainers, and timing set. What compression ratio should I be shooting for to get the maximum performance out of this setup? What do I need to do to get that CR?

What I know about my engine:
4 bolt main
492 heads, 64cc, 2.02/1.60
Performer RPM intake
Performer 600cfm carb
Accel HEI ignition
Flowtech 1.5" tube full length headers

TH350
3:73 gears

I'm looking for low - mid range torque. I don't see much need for 600+ rpms since I will be driving this on the street and not at the strip.

What should I be asking the mechanic prior to the rebuild to make sure it will be a quality job? I haven't ever rebuilt an engine. I have always bought crate engines in the past.

Thanks in advance.
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Last edited by Hugh Mongus; 03-07-2014 at 12:53 PM.
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Old 03-07-2014, 01:04 PM   #2
steelhorse
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Re: Engine rebuild info

I would go for around 9.5 to 1
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Old 03-07-2014, 02:20 PM   #3
TrkEnvy
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Re: Engine rebuild info

You need to know more about your motor to figure CR ratio. Lots of factors, chamber size.. You need to list your piston size 4.000 unless its been bored out. And you need the head gasket thickness and how far down the hole the piston is at TDC.. oh and if the pistons are dome,flat top or dished. I would say stay below 9 to 1 with iron heads. 10 to 1 with aluminium. Detonation sneaks up fast above that and you dont wanna have to run race gas or even premium if you dont have to. If you google compression calculator there is a bunch of them out there. You just need all the info I listed.
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Last edited by TrkEnvy; 03-07-2014 at 02:26 PM.
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Old 03-07-2014, 02:47 PM   #4
Hugh Mongus
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Re: Engine rebuild info

Chamber size on the 492's is 64cc per the inter-webs. This is the question I am asking. What type of machine work, pistons, etc do I need to tell this guy I want to reach the compression ratio I need to make everything work well together.

Example: I am assuming a rebuild includes new piston, but what type should I tell him I want?

I figure anything above a "normal rebuild" is going to cost me extra, so I want to make sure i get it right. I don't mind burning premium fuel as this is not my daily driver.
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Old 03-07-2014, 03:02 PM   #5
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Re: Engine rebuild info

If you just want a nice street driver stay around 9.5 to 1 compression. You can get that with almost any stock over the counter aftermarket piston. I really see no need to go higher than that in compression if you are just looking for a nice driver with some "pep". and the lowest I would even consider would be 9.0 to 1. Is your cam a 60102? I have never heard of a 10602.
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Old 03-07-2014, 03:05 PM   #6
Hugh Mongus
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Re: Engine rebuild info

Yes, 60102. Sometimes my fingers are faster than my brain. lol

I read many good reviews on these. I was going to get the Comp 268H that Jim recommended, but I read alot of complaints about valve chatter.
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Old 03-07-2014, 03:11 PM   #7
djgebert
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Re: Engine rebuild info

I think you will like that cam. I ran a 60103 in a street engine I had and it was a great cam. I have a 60105 in my 383 and it flat out screams. In my opinion the voodoo line of cams are the best all around hydraulic flat top cams available for a small block. Like I said I would just go for around 9.5 to 1. You can get a nice set of hypereutectic or plain cast pistons real cheap that will serve you well and are basically considered "stock" replacement.
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Old 03-07-2014, 03:21 PM   #8
Hugh Mongus
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Re: Engine rebuild info

Thanks. I was wanting the 60103 but I didn't want to mess with a higher stall. I had one before and it was a little annoying driving around after a while.
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