Rebeldryver's '70 Caprice Granny's Luxo-Muscle-Barge

[Scott Liggett]

I guess you have better luck than I do...

Better luck at what?

[squirrel]

with flat tappet cams surviving in big block chevies

[Scott Liggett]

We sell ton a lot of BBC's in performance, marine, and reman that have flat tappet cams. Since I have been there, none have come back for flat cams. People still think about the two-fold mistake that caused a lot of flat tappet cams a few years ago. First, was the EPA ordering ZDDP zincs removed from car oils. Second, the cam companies going off shore for cam blanks. The cam companies remedied this problem very fast. Third, are dumbass end users who can't follow simple break in instructions.

[cstmwgn]

We sell ton a lot of BBC's in performance, marine, and reman that have flat tappet cams. Since I have been there, none have come back for flat cams. People still think about the two-fold mistake that caused a lot of flat tappet cams a few years ago. First, was the EPA ordering ZDDP zincs removed from car oils. Second, the cam companies going off shore for cam blanks. The cam companies remedied this problem very fast. Third, are dumbass end users who can't follow simple break in instructions.

Comp has an EDM lifter that might also help with longevity. I use them on my flat tappet which has .653 valve lift (.378 lobe lift). I am on my second set of springs (Comp 930) with over 30k on the cam and lifters.

[Scott Liggett]

I don't like how the honing came out. Going to get the block bored and honed and line honed for new pistons. Will try to find a piston we stock at work that will give me decent compression. We have everything from industrial, marine, stock reman, and performance big blocks in our line up, should find something I need. Will have the rotating assembly balanced for the new pistons.

[squirrel]

I though you were planning on selling it?

[Scott Liggett]

I am. But I wont get jack for the car if the engine is smoking like a steam engine.

[yellomalibu]

I am. But I wont get jack for the car if the engine is smoking like a steam engine.

If your intention is to sell the car, go with cast rings and cast pistons if available in the dome size you need. There is no need to buy the more expensive pistons. Cast pistons worked fine from the factory. A "fresh rebuild" and a good running engine is sufficient for most buyers. High dollar, high performance racing components probably do little to add value to the car for most buyers. To me, it would mean the previous owner abused or at least used the car hard.

my .02

[Scott Liggett]

If your intention is to sell the car, go with cast rings and cast pistons if available in the dome size you need. There is no need to buy the more expensive pistons. Cast pistons worked fine from the factory. A "fresh rebuild" and a good running engine is sufficient for most buyers. High dollar, high performance racing components probably do little to add value to the car for most buyers. To me, it would mean the previous owner abused or at least used the car hard.

my .02

You are right. If I were going to keep the car, I would get forged pistons. I found a set of Probes that fit the bill on Summit for $450. The biggest challenge is to find the dome size I want for decent compression. I am figuring somewhere between 15-18 cc domes. That should give me in the neighborhood of 9.25:1. But, 9:1 to 9.5:1 will work.

[Scott Liggett]

I have been totally ignoring this car since I bought the truck. Time to get moving. I am taking in the block for machine in the next few days. Looking at some pistons. I can get Speed Pro's 9.76:1 hypereutectic pistons for $180.00, KB hypers that would fall 9:1 for $295.00 or, KB's Icon forged with 9.50:1 for $380; or some flat tops which would be barely 8:1 that we use at work for less money.


Remember I am running iron oval port open chamber heads on this engine. I drove this car for years with 10.25:1 compression with the oval port, closed chamber heads, but the engine had the original cam that mostly flat. I am looking into having the Speed Pro's dome milled down a bit here at work to drop the compression down. But, they may want to do that.

On the fence.

[Casey the Impala guy]

I'd get the forged pistons, 9.5:1 would be perfect for a driver. I'm sure it's in here somewhere but what size rear wheels and tires are you running? I Just got my Impala back on the road here in the last week too.

[Scott Liggett]

I'd get the forged pistons, 9.5:1 would be perfect for a driver. I'm sure it's in here somewhere but what size rear wheels and tires are you running? I Just got my Impala back on the road here in the last week too.

Those are 275/60/15's on 15x10 rallys. You will need to do some massaging to get them to work without rubbing, but not a lot.


What sucks is that i can get those 8:1 pistons for barely $100. Just once I would like to find the perfect thing for me and it not being the most expensive.

[Casey the Impala guy]

That's just how hotrodding is sometimes, you know?

What back spacing did you use and by massaging I take it you mean the bulge inside the wheel well? A solid bushing adjustable panhard bar would help with rubbing too I reckon. I have been talking to my uncle about cutting out the coil spring hump the frame and running a coil over spring in the stock location to try and fit some 315/60's.
Here in the next couple weeks I'm going to spurge on a rear sway bar for the car too, It's hard fixing an old car on a 20 year old's pay haha but I'm in this car WAYYYYY under what most think so I guess I'm doing pretty good!!!

[Scott Liggett]

They are 5 1/2" backspacing. I did heat up and bash the coil hump on the frame a bit. A little bit of wheel well lip trimming. I had to redrill the lower shock mount hole because the shocks were just close enough to the wheel to knock the balance weights off. I moved the hole up 1" and inboard 1/2".

I have been thinking of taking out the coil spring bulge on the frame as well on my '65 Impala. Looking at it, if you make it flush with the rest of the frame rail as it passes through the wheel house, I don't think it will cause issues with using the factory type coil spring.

Both this car and my '65 have aftermarket adjustable pan hard bars in their stock locations.

My '65 has 18x9.5 wheels with 5.25" back spacing on 295/45/18's and did not require any trimming or hammering at all.

[Casey the Impala guy]

Thanks for the info!!! I know you can get away with bigger tires on larger wheels, I talked to a guy with a 4 door that had 18x11's with 315/30's that fit front and back.
It's really cool to see another car like mine being done right instead on all that low rider and donk crap you see all the time.