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Looking at building a spare for my K5 where's what i have so far....

Stock 454 block
Stock crank & Rods
Wolverine Cam Lift is .595/.621, duration is 320/330
990's heads 2.25/1.88 ported
Hurricane intake
Looking @ either the H581CP60 or H581CP100 pistons which are a 30cc dome

So i was thinking w/
.060 pistons i'd do .010 deck clearance w/ a .039 gasket which would get 10.5:1
.100 pistons id do .010 deck and a .039 gasket and get 10.6:1

Or should I look @ more compression...
Setup is a TH350/NP205 w/ 3800 stall & 5.13 gears

Any input to how good this combo might?

Just to clarify, do I remember right that your primary use of the K5 is mud bogging?

Originally Posted by rspears

Just to clarify, do I remember right that your primary use of the K5 is mud bogging?

Yes I forgot to say that! Thanks for catching it...

The reason why I was thinking .060 or .100 over is because there the same price.

That cam will want minimum 11.5:1 static compression ratio, making power from 4000 to 7200. Big block Chevies are tough on flat tappet cams with stiff springs, so I would very highly recommend a solid roller cam.
Here's how to prep a flat tappet cam if you want it to live.....and even then, it's a maybe.
http://www.crankshaftcoalition.com/w...ips_and_tricks

I doubt you'd know the difference between 0.060" and 0.100" in the seat of your pants, so I'd go with the smaller overbore to save the block for another overbore later. I suspect you're going to need some pricey valvetrain parts if you're gonna spin a BB to 7200+. Grab your ankles.

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Originally Posted by techinspector1

That cam will want minimum 11.5:1 static compression ratio, making power from 4000 to 7200. Big block Chevies are tough on flat tappet cams with stiff springs, so I would very highly recommend a solid roller cam.
Here's how to prep a flat tappet cam if you want it to live.....and even then, it's a maybe.
http://www.crankshaftcoalition.com/w...ips_and_tricks

I doubt you'd know the difference between 0.060" and 0.100" in the seat of your pants, so I'd go with the smaller overbore to save the block for another overbore later. I suspect you're going to need some pricey valvetrain parts if you're gonna spin a BB to 7200+. Grab your ankles.

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Yep this is a Solid lifter cam. I picked it up for $125 w/ lifters, couldn't beat the price. Thats what i was kinda thinking about the bore, i run a 468 right now but not that much compression.

That's a flat tappet cam. Good luck.

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Yep, good luck . . . and find a source for racing gas.

Originally Posted by techinspector1

That's a flat tappet cam. Good luck.

Yes its a mechanical flat tappet......i decided against the roller due to not running it more than 5 times a year. The extra $500+ just for roller lifters...

Originally Posted by Henry Rifle

Yep, good luck . . . and find a source for racing gas.

I'm gonna run 93 then run the RaceGas additive or the Torco additive. So i can mix it while i go...

Originally Posted by Hoss Blazer

Yes its a mechanical flat tappet......i decided against the roller due to not running it more than 5 times a year. The extra $500+ just for roller lifters...

A pro engine builder that has become a friend writes an occasional column, and according to him "....with a flat tappet cam it's not a question of IF it will fail, it's only a question of when", and when a lobe or two decide to erode the micro-fine, highly abrasive particles of the cam flow with the oil and get in every nook & cranny of the engine, after abrading your cylinders & bearings. The only way to be confident you get it cleaned out is total teardown and hot tanking the block. You may only be running it five times a year, but every time it starts it's going balls out, full torque, pulling hard. I'd say that $500 would be good insurance, and

Originally Posted by techinspector1

Good luck.

So they should only sell roller cams & ban the rest? All I ever here on here is that....not to many budget builds anymore like this then!

built both the 100 over the block will be junk next time around sonic check is what i do for the 100 over bore you will see more gain with a 4.250 crank then the small gain in bore size .as a sold flat lifter cam use the face oiling lifter used some wd 40 and some 600 wet dry sand paper . go over the face of the lifter on flat steel or counter top and smooth the face some use moly on cam lobes only check all block bores that lifter truns free use good break in oil

Originally Posted by Hoss Blazer

Yes its a mechanical flat tappet......i decided against the roller due to not running it more than 5 times a year. The extra $500+ just for roller lifters...


I'm gonna run 93 then run the RaceGas additive or the Torco additive. So i can mix it while i go...

no its not 500 for only rollers new there is many ways to go and can cost much more but only 5 times a year there sets that are less that will work fine . i did tell you how to do this on a budget and told you i had a cam and psi springs that have low time on parts and to call and i would help you out and you never did so? i have many engines in off road use that use solid roller s cam .it would be very hard not to use a soild roller . the truth at times can be a bitch .rollers in bbc is very much the only way i build them as i seen more cams over time fail .but have built them with the edm holes threw the lifter body and used oil with zinc in it and that would be the same oil for a roller cam as well

Originally Posted by Hoss Blazer

So they should only sell roller cams & ban the rest? All I ever here on here is that....not to many budget builds anymore like this then!

Hoss, take time to read the history and understand the reasons for the advice. OEM's were already shifted over to roller lifters for improved efficiency when they started seeing catalytic converter warranty problems, and replacing an OEM converter was a high cost problem, guaranteed for 80K miles or more. The problem was due totally to high temp contamination by heavy metals in the exhaust, specifically zinc & phosphorus. The answer was to reformulate the motor oil, removing those constituents which had been added in the early days of internal combustion engines to deal with high pressure point loads on machined surfaces - cam lobes, rocker tips, etc, etc - the zinc & phosphorus are "slick" metals that crush, leaving residue behind that enhances lubricity. People immediately started seeing increased failure rates of flat tappet cams, even in mid-mileage engines that had previously been fine and shown no wear. New rebuilds often had failed cams within a few thousand miles. Hogwash? Then buy the flat tappet cam, pay no attention to your oil, and be unhappy when your newly rebuilt engine falls on it's face with a rounded off cam lobe or two.

Best of luck to you with your toy. Perhaps you'll be the exception to the statistics and enjoy a long run with flat tappets.