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Old Jun 28, 2010 | 09:58 PM
  #21  
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Need to make sure what pistons are in it. They may be domed 11.0 or flat tops....or replacement style flat tops that are even lower compression or even sumps. Need to know that for sure before ordering heads. With a 327, compression is lost quickly as you add cc's in heads.

Is it in good shape now? No smoke when at WOT? Because when you start to add power and cylinder pressure as well as RPM....any issues will be magnified quickly!

Again, the MSD is no big advantage. If dist is good they will spin 7000+ rpm without issue. Adding an MSD box will help starts and low speed stuff...but no real max power really.

If it's got forged pistons and is well built it's a 7000+ rpm motor. If it's cast pistons then you're in the 5500-6000 safe area.

400-425+HP is easily doable with a streetable 327.

I like little circle track flat tappet cams. One that we use regularly is the Crower #350. Great little cam, doesn't hurt stuff, sounds good, drives great....just good all around cam.

The old LT-1 cam isn't bad either.

JIM
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Old Jun 28, 2010 | 10:31 PM
  #22  
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If it was mine, I would keep it all GM and go for a set of FI pistons, 70 LT1 heads, and either a 30/30 or LT1 cam like Jim suggested.....You don't need any of that roller junk to add to the cost and minimal benefit to the combination...93 octane would work with these parts and give you good service with a bunch of available HP...which would be up to you to retrieve it....The rest of the parts could be reused off the engine....
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Old Jun 28, 2010 | 10:38 PM
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okay on the dual 4's Find out what port size they have and buy heads with ports that match. You need to look at the pistons. It is hard to get compression with flat tops or dished in a 327. So you might want to go down to like 58cc heads.

Crane makes a power max 238/248 solid flat cam. It is not as radical as it sounds because it is ground on a 114 lc I actually had it in a tunnel rammed .060 327 in a street rod years ago with 200 cc heads and 2.055/1.60
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Old Jun 29, 2010 | 01:47 AM
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I don't know of a distributor on the planet that will deliver full spark to 7K RPM. What I typically see on the dyno is voltage falloff starting around 3500 for the cheap stuff and around 4500 or so for a decent aftermarket HEI. Especially in high CR engines, a high-energy spark is crucial.
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Old Jun 29, 2010 | 04:32 AM
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Haha, tough but helpful crowd!

Alright...so what everyone is saying at this point....is that I won't be able to pick out anything from Afghanistan, to have ready to be installed by the time I come home from deployment, because I can't get exact measurements of everything...which EVERYONE does when ordering heads/cam?

But if it is still possible for me to pick out stuff...then can you guys throw up actual parts from vendor sites so that I'm still not guessing on things, and have actual parts to look at and compare? That would be a great help!

Again...thanks for all the help everyone.
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Old Jun 29, 2010 | 04:41 AM
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Did some research:

My compression: 11.0:1
4 speed Muncie
Gearing: 3.36:1

My intake/carbs are these, but no info on port size: http://www.summitracing.com/parts/EDL-20254/
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Old Jun 29, 2010 | 05:09 AM
  #27  
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Originally Posted by Birdman
Did some research:

My compression: 11.0:1
4 speed Muncie
Gearing: 3.36:1

My intake/carbs are these, but no info on port size: http://www.summitracing.com/parts/EDL-20254/
That intake uses 1.28 X 2.09 gasket Which is the same as a Felpro 1205. So it is like the mid sized head ports.

As to 11:1 I would have to see it to believe how big the domes are.
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Old Jun 29, 2010 | 10:15 AM
  #28  
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Is there somewhere on the car (VIN/engine block) that I can have my dad go check out to see what it would be?
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Old Jun 29, 2010 | 11:18 AM
  #29  
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I'm doing the same thing you are right now. I have a 1960 with a 327.
I used the suffix code on the block front to ID the engine. This is a good web site for suffix codes: http://www.chevy-camaro.com/chevy-ca...s.asp?group=11.
The next helpful number is the head casting number. With this chart you can find the head volume: [url]http://www.caribbean-joe.net/vette/data/Detailed%20Head%20Casting%20Numbers.htm.
You still may have some decisions to make. I my case I have a 1963 250 hp engine. I know the 250 hp came with flat tops and had 10.5:1 CR. The heads are 60cc. If I go with a 62cc chamber I will now have 10.25:1 CR. TFS have a 62cc head most others have the 64cc heads. If I go with 64cc chambers I'll be down to 10:1CR.
Not sure which way to go yet.
This info will give you something to think about.

Last edited by jmurray8201; Jun 29, 2010 at 12:36 PM. Reason: Better head casting chart.
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Old Jun 29, 2010 | 12:19 PM
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As an aside, it's important to also factor in the head gasket and deck height into the CR caclulations. Deck height on a factory engine is typically .025, but I've seen it all over the map. Stock head gasket thickness is often .041 or thicker...giving an .065+ quench vs. the ideal of around .040...so think about this as well.

You can make a good guess, but it's worth spending the time to actually find out. The heads are coming off anyway, right? So wait until you have a chance to do this and ensure you don't make an expen$ive mistake.
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Old Jun 29, 2010 | 12:54 PM
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So just to clear at least one thing up, the above H/C package will NOT work on my engine, and would be a complete waste of money/parts???

And this sucks that I can't seem to be able to buy anything without having to make a ton of measurements, which I'm not able to do for 6 months. It'd be simpler to just buy a crate engine it seems, though I don't want anything other than a 327 (or 427 I guess).
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Old Jun 29, 2010 | 01:16 PM
  #32  
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I wouldn't say that combo 'won't work' but IMHO it's a poor overall fit for the engine. Do you want the most bang for the buck, or do you just want to bolt on parts?

Building a performance engine takes more than just bolting stuff together. It does suck sometimes, and it is easier for sure to get performance "out of the box"....but a smart guy with a little work can make a lot more power than a package deal, albeit for a bit more cash

It's just the way it is - I can't count the number of "rescues" I've done in my shop from good parts well-assembled...but were total mismatches and the combo just didn't work.

Last edited by billla; Jun 29, 2010 at 01:49 PM.
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Old Jun 29, 2010 | 01:48 PM
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And, by the way - thank you for your service. If there's anything I can send you, your buddies or your unit from the home front, please drop me an email. Last shipment we made over there was a toaster oven filled with muffin mixes

http://www.soldiersangels.org/

My stepson returned from a year in Iraq in Feb, and he's deploying to Afganistan in November.
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Old Jun 29, 2010 | 03:14 PM
  #34  
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Originally Posted by billla
and, by the way - thank you for your service. If there's anything i can send you, your buddies or your unit from the home front, please drop me an email. Last shipment we made over there was a toaster oven filled with muffin mixes

http://www.soldiersangels.org/

my stepson returned from a year in iraq in feb, and he's deploying to afganistan in november.
and a great big thank you to both you (billa) and birdman!!!!!!
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Old Jun 29, 2010 | 04:51 PM
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Originally Posted by billla
And, by the way - thank you for your service. If there's anything I can send you, your buddies or your unit from the home front, please drop me an email. Last shipment we made over there was a toaster oven filled with muffin mixes

http://www.soldiersangels.org/

My stepson returned from a year in Iraq in Feb, and he's deploying to Afganistan in November.
Hey I appreciate it billa! I think we'll be fine...we get a few packages from anysoldier.com sometimes. However, our mailing system is so messed up right now, and we are at such a remote place, that if you sent anything it might not get here till we return back to Italy.

This is my second deployment to Afghanistan..so if he has any questions/worries about it, or what to bring and tips...then feel free to email me or message me here.
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Old Jun 29, 2010 | 10:09 PM
  #36  
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The main thing you're looking for is whether it has domed pistons or not. Maybe your dad can pull a plug and roll the motor over until it's at TDC and feel around through the plug hole with a screwdriver to see if the piston is flat or has a dome on it. That will tell you a lot.

I Know you want to order stuff...but you can have just about anything you want within a week when you get home. That will give you enough time to pull it apart and clean stuff. In fact, you might think about pulling motor. It's a lot easier to work on, you can clean and inspect things easier, paint stuff up a little and just do an overall better job.

I'll give you an example of one we have in a buddy's '65 convertible. It's a .060" over 327 with a set of ancient (70's!) TRW 11.0 pistons, a set of World Products iron heads and that little Crower cam I mentioned. It runs high 12's on plain street tires with 3.36 gears. Any of the aluminum heads you're looking at will outflow the ones he has.

All your other parts....cam, intake, carb etc can be had now..just need to figure out what size chamber to get the heads in.

JIM
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Old Jun 30, 2010 | 12:28 AM
  #37  
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So in '68, there was no set piston type? What if I BUY pistons? Which should I choose?

And what do you think about these (dome/flat)? http://www.pawengineparts.com/shoppi...9284&catid=845
http://www.pawengineparts.com/shoppi...9282&catid=845

Also: Since you said I could get a cam now....would you recommend a flat tappet or roller? I've got the money for either.. What about specs? I want something that would have a nice roughish idle (but still streetable) and that will give me the best gain... Or if you could look at the above ones I had mentioned (in the package or separate) and go from there?

Thanks Jim

Last edited by Birdman; Jun 30, 2010 at 12:56 AM.
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Old Jul 1, 2010 | 05:20 AM
  #38  
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Bump...
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Old Jul 1, 2010 | 09:46 AM
  #39  
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I think the struggle, for me at least, in trying to give a good answer is that there are so many variables.

If the shorblock is in good shape and you want to top it, then we need to be 100% sure of the current piston volume. If you're willing to gamble that the engine is indeed untouched, then the year of the 'Vette, casting number of the blocks and heads along with the stamping from the pad in front of the head will give enough information to say "OK, if this hasn't been touched, then this is what we have". This stuff is all easy to find and doesn't require a major teardown - just pulling one valve cover and a little contortionist work with a flashlight to get the block number.

If you want to start from scratch with a new build (new pistons), that's a different story...and well outside of your budget.

I approached this as the most bang within your budget, which to me means a good set of heads and a retrofit roller cam - which should be right in there.

Engine designs start from what I call a "pivot point"; it's one design criteria that's frozen and everything else revolves around it. It might be an existing shortblock, a budget, an HP target....but something as a foundation to the design. Doesn't mean it can't change - and almost always does - but generally I start from the foundation to a pretty specific design. If that design meets the overall goals, then we're good to do a final design. If not, we back up a bit and adjust course. But when the variables become infinite, the design tends to "dither", it gets hard to make any specific recommendations. Hope this helps

Last edited by billla; Jul 1, 2010 at 10:48 AM.
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Old Jul 2, 2010 | 05:48 AM
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I see what you're saying, and thanks for all the input billa.

It almost seems that it would be cheaper to just buy a used built up engine, than try to build this one up...because at this point I want to replace the pistons as well.. Problem is, I want to keep the 327 (or get a 427) really bad...and not many people are selling built up ones..
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