Hey folks, browsing craigslist I picked up a complete 454 for a song. Dudes who had a ricer race shop were going to put it in a boat, and then got distracted by something else. Its 4554 4-bolt block and 049/113cc heads. All valves and components are new and all machine work and assy is complete sans mounting the heads. The thing is super clean, has a deep pan and came with polished intake and micro starter among some other goodies.

Now the issues:

They were building it for a boat and installed a Comp XM 262-12 which seems anemic to me. Back to it later.

The real issue I believe is with the chambers. They installed what seem to be generic flat tops with 10cc relief. With the 113cc chambers I dont think were going to hit the needed compression to make some power.

So is replacing the pistons the only option here? I want a decent street motor (450HP is plenty)and since this was an unplanned project want to keep the budget tight. At this point I'm thinking a set of pistons and cam upgrade. But I would love to hear some options which use these pistons.

Here is a shot one in the hole, and a follow up of my current rough DCR calculation. Is my assumption of 10cc a good one?

All advice and idea's are welcome.

 

049 are rated 119cc usually 120 to 122. With .027 head gasket, .016 in the hole 10cc dish you are looking at 7.64:1. With 100cc heads about 8 75. Maybe look for a set of 215 heads.

 

Wow that would have been horrible. If you replace the pistons get the assemble re-balanced.

 

With that low of compression, maybe the owner had planned for some type of boost? Who knows?

Your Dynamic CR should be well over 8 when all is said and done. Thats where the power is.

You might be better off leaving the shortblock alone (except cam) with those brand new slugs and try to source some smaller chamber heads.

 

According to all the specs I've seen 049's are 113 CC Open Chamber??...but they will be measured for sure. I'm thinking the cheapest way out is to buy a set of 20cc dome pistons and and a 282 cam. I really dont want to pay big $$$ for a set of heads and then be sitting on these. So with a 20cc piston here is what I get.

Now my other question is I have read opinions that for BBC DCR should be closer to 7.5:1? Any opinions there?

thanks again guys!

 

Now you're talkin'. Big difference on intake valve closing too.

Static: 10.3
Dyna: 8.2

What about that cam advance? Is that an 8? Too much, no top end power.

 

Definitely need pistons and a cam. That's the cheapest, most effective fix for this. You will have to rebalance it, which isn't that expensive.


10-1 pistons and a good SFT cam and its a 500-550hp motor with stock 049s. 450hp will be cake, even with a HFT cam.

 

The cam advance is actually 4*. The calculator wants crank degree's and says cam x2....so the entry=8.

 

Ok, gotcha. I need stronger glasses for fine print.

 

What calculator are you using?

 

Its not mine but I believe its a similar program to United Engines & Machine. There are two ways to get dynamic CR specs. Long math or let their calculator do it for you using the intake valve closing event.

 

I'm using this one...

https://www.jeepstrokers.com/forum/calculator/

 

Get a piece of plexiglass and drill a hole off center. Go to Walmart and get a flavor shooter for injecting broth into meat. Looks like, cuz it is, a giant hypodermic needle. 25cc graduated. I checked one against a graduated cylinder and accurate enough for cc'ing chambers. 5 bucks to cc your heads. Now, compression ain't the be-all and end-all it is cracked up to be. You get 4% power increase for each point of compression up to 9. 2% a point from 9 on up. If those 049's have a valve job on 2.06 stock valves, I would think about smaller chambered heads.

 

The close chambered heads won’t even get him up to 9-1 compression with flat tops. Dome pistons are a must to get anywhere near 10-1 compression. And the close chambered heads don’t flow nearly as well as his 049s. A bump from his 7.8-1 comp to 10.0-1 is an easy 40-50hp.

 

Thanks for all the feedback to date. I've verified the deck is .035 and the chambers are indeed 113cc. So I'm going to a 24cc dome and here is what I get with them plus the 282 cam. So the flatops and cam are coming out and getting replaced. ... I'll keep the thread updated with progress.

 

if they are stock chevy rods with 3/8ths rod bolts, replace them too...

 

Some 100cc heads are better than others for chamber shape. These are closer to small open chambers.

 

Thanks for the input, and on the heads as well. These heads are recently worked with new valves, guides and studs so they are going back on. If the rods are in good shape they will go back too. This wont be going in a racer by any means. Good street cruiser is all I need.

 

Good solid plan...keep the 049s.

3/8s rods with good rod bolts are fine. You can easily hold 600hp+ on 3/8” rods.

Just make sure to get the pistons sized correctly so your piston to wall clearance is tight....(since your block has already been bored and honed.)

You should have a nice combo....

 

Your basic Walmart 4 buck chamber cc'ing device...