10.5:1 Pistons for '66 273 Block w/ '67 920 Heads

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gorgerider

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I'm having trouble tracking down a set of 10.5:1 pistons for the 273. I've searched for the last hour and can't find a source. Questions:

1). How do I search the usual suspects (parts houses/fleaBay). What engines will work for what years?
2). Where can I find a set?
3). What will the compression really end up at w/ the close-chamber 920 and a thinner gasket? I understand the volume to be 57cc.

Thanks.
 
Go to the small block engine forum on this site and use the search function. Type in your query and it will return several pages of information of the type you are asking about. Quite a few of us are doing that build in some version or another.
DR:coffee2:
 
egge.com
Piston # L2222-8, Cast, 10.5:1, a bit heavy, but an option.
I am sure others will chime in with alternatives ...
 
I'm sorry for not being able to separate the stuff I read in these threads. I haven't run across my exact build and I don't know enough to determinewhich other applications are relevant. 318 v.273 v. 302 heads v. 320 heads v. etc. This is my first MOPAR and the learning curve is a little steep for this old brain, hence the remedial questions.

I've checked Egge and couldn't quite put their products list together. I know the more I read, and there's a boatload of it, the better questions I'll be able to ask.
Thanks for your patience.
 
If Egge is where you land, it is best to call them. I used their 10.5:1 pistons after talking to their tech support. There are other options out there though. Get your checkbook out:)
DR
 
I too used Egge high compression pistons in my 273 build. With the stock small chamber 273 heads and a thin head gasket, I ended with 9.6/1 compression. Call Egge for more info. The pistons were very good quality and very consistent size and weight. The link to my build is just below here. tmm
 
When I built mine back in the 90s you could get TRW hypereutetic pistons. You could contact them and see if they will still make them to order.

To answer part of your question, the 273 is the only engine with that particular bore size -- no other pistons will fit. Don't bother looking at 318, 340, etc.
 
Thanks for the feedback, folks. I read Toolman's thread and found it full of stuff I can use. Thanks for pointing me in the right direction. And nice thread, Mike.

One of the things I don't see much of is use of 920 heads. The other stumbling block I run into is the terminology:

"Heads #920 runners opened up to 340heads size, bowl blended, valve bosses grinded down, exhaust runners and combustion chamber polished......."

This stuff leaves me scratching my head and the result is my asking poor questions. My experience is with stock English stuff like E-Type Jags, the '57 MGA stocker I built in 1978 (my first car), and other MG's and Triumphs. I've never done the muscle-car thang. For example, I keep looking for an intake that'll take S.U. carbs for a /6 application!

As to the original purpose of this thread (pistons), the Egge website left me stumbling, too. I did call and find a set available from Falcon Performance, but their supplies are waning. From reading your threads and others, I know real 10.5:1 is a pipe dream, but that's just fine with me as I still want streetability. Mid 9's are just fine with me. The 10.5:1's and a mild cam is all I really need. I've even foregone the idea of headers, and their cost and hassle, and will go for manifolds. I just have to track down a set. I currently have a complete hydraulic valve train and will stick with it. And no matter what I'll need a V-8 center link.

I'm early in this process and still trying to figure out and/or find the stuff I'll need to complete the V-8 swap and other stuff for the build. That includes front end stuff, 10.5" flywheel and clutch setup, front discs, and power steering (if a '64 Valiant setup I have access to will work, I'll get it).

I've gleaned a lot, but more information seems to generate more questions. I appreciate your patience and guidance.


Coffee is gone. Cigar is done, Seahawks are on the field. Gotta go.
 
The 920 heads (66 and 67 273) are the same as the 178 (early 66) and 234 (late 66) heads. I never have found out why the number change between the heads. They all have the same valve size and rocker design. A slight difference in ports could be the difference. My 273 had a (if I remember correctly) 178 head and a 920 head. There also was a newer rod bearing on one cylinder. I imagine something broke and a rod bearing and head had to be replaced.
 
For example, I keep looking for an intake that'll take S.U. carbs for a /6 application!

Can't really help you with the other stuff. Your best best in finding a slant manifold to suit a slant is most likely eBay.com.au (Aussie eBay). Here's one listed for sale:

http://www.ebay.com.au/itm/CHRYSLER...769917?hash=item4189dbfcbd:g:itkAAOSw~1FUVs5P

I sold a really nice complete triple SU manifold and rebuilt HIF6s not long ago to a guy over at .org They are out there!
 
Hah! Leave it to the Ozzers to stick w/ their Brit roots. Too bad I chose the 273 route. Oh, well. Maybe I'll put the /6 on the shelf if I want to ignite my uniqueness. Until then, it's designated as a boat anchor or really big doorstop.
 
I may go Italian on my wagon's slant - the manifold came from OZ and the 45's are genuine Italian Webers
 

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I just get all wet and steamy over multi-carb setups. I've always walked away from Weber conversions because I've always understood them to be finnicky as hell when it comes to balancing and tuning. Not that S.U.'s are much better, they're just the devil I know.

I read the thread. Veryu interesting information about compression balancing. The differences in piston manufacturers was a bit startling. I've used Kanter for stuff associated w/ a '57 Buick Century 2DHT I played with for a while and found them to be pretty proud of their stuff. I don't know if I have the chops for all of it, but it'll be in the mental hopper as I stumble along. I'm going w/ hydraulic valve train so the details of rocker arm, tappet, pushrod stuff won't likely be in the cards. Not a race car, just a solid, fun driver is the goal.
 
/6 for webers or SU? Just make your own. Get some flanges off Ebay and some 1.5" pipe and start welding. The runner length will be whatever fits, the shorter the better for I.R. style intakes. You can buy intakes from Oz or specialty retailers but the cost is unreasonable plus the cost of the side draft webers, might as well EFI it from parts off a M series BMW with its I.R throttle bores. There is a guy somehwere here or .org that has 6 Mikunis off a slant, says the pedal is pretty heavy with 6 return springs. I think Argentina had an intake that used 6 Briggs and Stratton lawnmower carbs (no kidding!) something about using in country parts for a racing class.
 
I just get all wet and steamy over multi-carb setups. I've always walked away from Weber conversions because I've always understood them to be finnicky as hell when it comes to balancing and tuning. Not that S.U.'s are much better, they're just the devil I know.
The biggest thing IMO with Weber DCOE's if that there are SOO many parts you can change....it can bet really confusing. Especially the emulsion tubes which really can change the transition into mid range RPM's. About 2 to 3 times the parts to change as in a Holley.
 
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