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Discussion Starter #61
Seeing that it's your 1st build.Remember measure twice.
Been reading a lot and looking through old builds. Once I have a list of everything I'm going to call a rep from summit or jegs just to make sure I'm in the clear.
 

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Discussion Starter #62
You also need to make sure the springs on the aluminum head are compatible with the hydraulic camshaft. I'd still go with a hyd. roller.
Can you suggest one to me please? To many to choose from. Haha
 

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Discussion Starter #63
Ganoman, I think the aluminum heads you just purchased along with the cam/lifters and the intake manifold you posted would really wake your engine up... while still maintaining decent street manners. Be sure you also use the appropriate components as Ericnova mentioned in post #55. You are also going to need the correct thread sealers, assembly lubricants, and gaskets for this task.

Note: Once your heads are removed from the engine, it might also be beneficial for you to find out how far down the piston sits in the cylinder bore at TDC (piston to deck clearance). You would normally use a Deck Bridge and a Dial Indicator to determine this measurement (see below).
View attachment 407859
The purpose of this is to help with the selection of the appropriate head gasket thickness to achieve a desired "quench" height. If the quench distance is too large, engine detonation is possible (even with optimal ignition timing). If the quench distance is too small, engine damage could accrue (piston could contact the head at higher rpms). Below are a couple of write-ups that explain quench in more detail. As you can see, there is more to building a well performing engine than just bolting on a bunch of aftermarket parts.
What Is The Ideal Quench Height? - Hot Rod Magazine

You could probably get by with your stock torque converter, but a little bit of a higher stall speed than stock would better suit the cam you selected. I have attached a link to Edge Racing Converters... and I think the "Mild Street Edge" would be perfect for your build. I run the "Street Edge" converter in my Nova and love it!
Ok I will get the gaskets and oils and stuff once I order everything. Thats nbd

I will buy that tool to check the measurements of the piston. The fact that it looks like my engine was decked so much that the casting marks on the front passenger side of the block are gone makes me 1. nervous that is needed a lot of work. 2. Excited that maybe it's been bored .30 over. Fingers crossed.
 

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I see Eric beat me to the answer of what I was after. The head change alone will wake the car up on many points. Compression, flow and weight. The intake is a good choice, and then the cam is mild but an improvement. I think that the parts are fine.
 

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Discussion Starter #65
I see Eric beat me to the answer of what I was after. The head change alone will wake the car up on many points. Compression, flow and weight. The intake is a good choice, and then the cam is mild but an improvement. I think that the parts are fine.
Would an Edelbrock air gap intake be even better?
 

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Would an Edelbrock air gap intake be even better?
The heat retained by the Performer RPM with no air gap will make street driving and fuel mileage a little better.....if this is going to be more of a max effort deal that see's a lot a strip time the Air-Gap would be a handful of HP better.
 

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Discussion Starter #68
The heat retained by the Performer RPM with no air gap will make street driving and fuel mileage a little better.....if this is going to be more of a max effort deal that see's a lot a strip time the Air-Gap would be a handful of HP better.
God now I don't know lol.
 

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Can you suggest one to me please? To many to choose from. Haha
Lot's of different companies making good products. I put a Howards in my car and have been happy with it. The main thing is to know what you are looking for. What you are really going to be doing with your car. In my case I wanted to be able to get out and drive my car but also wanted performance when I wanted it. I put manual disc on my car so vacuum really wasn't important so I went with a larger street camshaft. I also put a 2400-2600 converter in my car to make it more drivable in traffic. I would suggest picking a company and calling them and talking to them about what you are going to be doing and they will walk you thru the process of picking the right camshaft for your car.
 

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Mike - 74 Nova Baltimore, MD
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Ganoman, Decide what your goals are first... then purchase your parts.
As previously mentioned by myself and others... the heads, cam, and intake you posted will work out well for a mostly street driven 350 small block Chevy.

While a hydraulic roller cam is recommended, installing one in a non-roller block does involve using specific parts and also comes with higher costs.
If you decided to go with a hydraulic roller cam, you might need to update the springs in the heads you just purchased to a stiffer rate and higher max lift... or return the heads you just purchased and buy the Promaxx 2169HR.
With a hydraulic roller cam, you also need to purchase retro-roller lifers (these can get expensive) and install a cam button with a stronger timing case cover to eliminate cam walk.

P.S.... Be sure to take lots of photos during the disassembly process to use as a reference during the assembly phase. Also, separately bag and label all fasteners and mark all connections so they can be reinstalled correctly.
 

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The main thing is to know what you are looking for. What you are really going to be doing with your car. In my case I wanted to be able to get out and drive my car but also wanted performance when I wanted it. I put manual disc on my car so vacuum really wasn't important so I went with a larger street camshaft. I also put a 2400-2600 converter in my car to make it more drivable in traffic. I would suggest picking a company and calling them and talking to them about what you are going to be doing and they will walk you thru the process of picking the right camshaft for your car.
I second this... I wanted good low end torque since I seldom go over 4500 RPM and also have overdrive and wanted to use it at lower speeds .. and something easy on my valve train... I first found a Howards cam that looked like it would accomplish these objectives and then called their tech dept to see what they thought. They affirmed my choice of a Howards CL112571-12S Street Force 2 .flat tappet hydraulic cam. Below is a picture of a virtual desk dyno results. It's a 350 with 9:1 pistons and 76cc pocket ported heads 2.02/1.60 valves--nothing real special- but is great for cruising and provides me with enough thrills for a street car. Easy to drive on the street.

407907
 

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I'll be honest with you, I would check out BluePrint or GM crate engines, they are both reasonably priced and assembled in controlled environments where the results are usually good. I usually build my own stuff because I enjoy it and am a lifetime auto tech but even I admit I could probably save a lot of time and definitely a lot of money just going crate or BluePrint. My last build was a 408 sb that I had way too much money in and during break-in a brand new Morel roller lifter went to crap and the results were bad, real bad. In the end I could have got a built and dyno-tuned 434 from a guy in my area that specializes in them and warranties them for 2 years. Which is just what I'm doing now!!
 

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Eeewww, not good. Cast dished reduced height rebuilders piston....if the block isn't decked a bunch 12-13cc dish plus 1.540" compression height being another .020" farther down the bore @ TDC(for a whopping .045" total) from stock is another 5cc lost volume means 8.65:1 compression with a 64cc head and composition gasket (Fel-Pro 1003) and awful .086" quench clearance which is effectively zero quench effect and increased detonation sensitivity.
At best 9.15:1 compression with a .015" thick coated steel shim gasket(Fel-Pro 1094, not really recommended for use with aluminum heads) but still lousy quench clearance at .060".

Sucks you've gotten stuck with such a crummy piston choice by the previous owner of the motor

Maybe you'll be lucky, it was done a short enough time ago that the cylinder walls are in good shape and no wear ridge at the top, so it could be ball honed and a new set of hyper pistons and rings swapped in at a moderate expense. This really needs a flat top with at minimum 1.560" compression height.
The Summit Racing hypereutectic #SUM-17350C-040 with correct 1.56" height and coated skirt would be a good budget choice for a under 500HP deal.
They would get you to 9.75:1 on an undecked block with a .041" thick head gasket. quench would still be on the wide side at .066" but this isn't as big an issue with aluminum heads
If the block happens to have been decked a good amount.020-.025" compression ratio would come up to 10,25:1 with the same gasket.
 

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All I see is more $$$, you're at .040 with a block that has been decked by how much?? I've been down this road in the course of 35 years in the trade, you are now looking at having a machine shop with actual reliable measurement equipment figure out if it can be saved and at what cost? You're most likely looking at boring to .060 because the machine shop is going to find the cylinders need more than a simple hone. At this point you would spend less buying a new built shortblock from say BluePrint or Skip White. Then you need to decide on a cam and head package, I wouldn't use a flat tappet cam today if someone gave it to me for free. I'd call Chris Straub and have him set you up with a roller set-up and a set of his aluminum heads (off brand aluminum set up by Scott) and you'll still save money over dicking around with what ya got there. I know many people may disagree but since this is what I actually do I know what I'm talking about.
 

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Discussion Starter #77
I was hoping it might be a good thing. Sigh.... Now what should I do. Already bought the heads.
 

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Mike - 74 Nova Baltimore, MD
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So put it as simple as possible for me men. This ain't gonna work?
It depends on whether your block was decked... and if so, how much was is decked?

To other engine builders,
It's been a little while since I played with all of this math... but wanted to get your thoughts on this.
Ganoman mentioned that the block ID stamping on the passenger side block surface was no longer visible. This makes me believe this block was decked during the previous rebuild.
407934

What if the person who rebuilt this engine had the block "zero decked" (crank centerline to top of block bore = 9.00"). If that is the case, the existing pistons would still be .020" in the hole... but Ganoman could use a Cometic MLS head gasket at .023 thick (compressed height). That would give a quench height of .043 (plus the volume of the piston dish)... and with the Promaxx 64cc heads provide about 9.4 to 1 compression.
Even though the Cometic head gaskets aren't cheap, they would still be more economical than changing the current pistons.
  • If my calculations are incorrect, please feel free to call them out... as I am a little rusty at this.
If it were me, The first thing I would check would be the piston to deck clearance and decide my next move from there. This rebuild could turn into a real money pit... where the funds would be much better spent on a crate engine.
 

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I would say your best course of action is to have a good machine shop evaluate it, I know that's easier said than done as good automotive machine shops seem to be a dying breed. Up here in NE we had several in the city (most were excellent) about 15 or so years ago, now I have 2 guys I trust, 1 is 35 mins away, the guy who does my 434"s is well over an hour so I know how it is. But even if it turns out it's really not saveable since you already have the heads you could get a nice shortblock and bolt them on, CNC motorsports as well as Wolverine has them with piston options that will work with your heads and then select the right cam and you'll be good. A friend of mine recently bought a Wolverine 350 shortblock for under 3K and it looked to be nice stuff.
 
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