496ci revamped

[Indycars]

That's great then, good to hear! It would mean making the gap too big if you needed to square up the rings
after the gap was set.

 

[Speedlink1973]

Just to note:
I did not check it here it was just for photos purposes
You can see how square it is

 

[Indycars]

Looks good to me!

 

[Speedlink1973]

Got piston dome compression numbers Grumpy
24.4 cc was supposed to be 25cc

At a depth of .569 and a diameter of 4.310
It was 112cc
Calculator said it should be 136.4 cc
- 112cc = 24.4cc

Oh I used 91% alcohol and a few drops of
Red food coloring.
When I was done I tipped block upside down wiped it out and wiped down bore with WD-40
Then put my quick set powder on it again.

 

[Speedlink1973]

Looks good to me!

I gapped the rings at .024 just in case I want Nos later on that gap per total seal
Is good up to 150hp shot

 

[Maniacmechanic1]

I gapped the rings at .024 just in case I want Nos later on that gap per total seal
Is good up to 150hp shot

One area I have found with Power adders working in a Race Shop last year Building engines from bare block to turn key is large piston ring gaps do not matter at all.
I gapped all piston rings for 400 + Hp on Top of base HP N/A.
To cover my Butt.
Every car was Turbo Boosted.
Some had 44 psi Boost.
None blew up.

 

[Speedlink1973]

One area I have found with Power adders working in a Race Shop last year Building engines from bare block to turn key is large piston ring gaps do not matter at all.
I gapped all piston rings for 400 + Hp on Top of base HP N/A.
To cover my Butt.
Every car was Turbo Boosted.
Some had 44 psi Boost.
None blew up.

I wasn't too worried about a bigger gap
Just for the fact it's a gapless ring.
I almost took them bigger, but I doubt I go with Nos,
If anything I will jerk the pistons out put flat tops in drop compression to 8.5 to 9:1
And put a under the hood low profile supercharger on it and run 6 to 8 psi of boost
I'm kinda a mad scientist, it's my tinker toy.

 

[Maniacmechanic1]

I wasn't too worried about a bigger gap
Just for the fact it's a gapless ring.
I almost took them bigger, but I doubt I go with Nos,
If anything I will jerk the pistons out put flat tops in drop compression to 8.5 to 9:1
And put a under the hood low profile supercharger on it and run 6 to 8 psi of boost

It takes a Large or Huge Supercharger to feed a 496 ci BBC.
Gets expensive.
But 1000+ Hp easily done in theory.
Figure $8,000 cash more to Supercharge.

 

[Maniacmechanic1]

Math always looked good on Grumpy 496.
Build it.
Tune it.
Get the car dialed in.
See What it does.

So much torque just impossible to put down all on street tires.

 

[Speedlink1973]

It takes a Large or Huge Supercharger to feed a 496 ci BBC.
Gets expensive.
But 1000+ Hp easily done in theory.
Figure $8,000 cash more to Supercharge.

I actually bought this, but sent it back
Because I didn't want to change pistons,
But ended up changing pistons anyway

 

[Maniacmechanic1]

I actually bought this, but sent it back
Because I didn't want to change pistons,
But ended up changing pistons anyway

Little guy for a Big 496.
Should deliver nice Normal Aspirated.

 

[Speedlink1973]

Little guy for a Big 496.
Should deliver nice Normal Aspirated.

At that time I didn't know much,
I'm a bit more educated than I was then thanks to mostly you guys.
Think my N/A motor will do just fine

 

[Grumpy]

a 177 on a 496 bbc is good for visual effect but its going to be not only nearly useless once you exceed about 5000 rpm,for providing significant boost levels, regardless of pullie ratio selected,
\its probably going to offer minimal or no gain at all over a properly built N/A high compression 496 bbc simply because it can,t keep up with the the engines air flow demand,
and still produce any worth while boost volume.
roots superchargers can be driven to over engine rpm,
with changes in the drive vs driven belt pullies, rather easily but as the rpms increase so does heat and a loss of efficiency.
Im certainly not saying a 177 supercharger won,t boost average power,
but the gains will be nothing close to what you could expect from a properly sized super charger like an 871 or better yet a centrifugal supercharger with a properly sized inter-cooler.

much better match to a 496 BBC
https://www.carid.com/weiand/8-71-s...MIhuaYkZ2m3AIVC7XACh0IKA_UEAQYBSABEgK_kPD_BwE

https://www.procharger.com/automoti...eted/gm-carbureted-aftermarket-efi/sbbb-chevy

https://www.procharger.com/automoti...t-efi/sbbb-chevy#/p-1x-and-d-1x-superchargers

The numbers related to these blower sizes, such as 142, 177, and 256, relate to the amount of air in cubic inches that is pumped by the blower in one blower revolution. The 6-71 and 8-71 designations refer to the original GMC diesel engines. Table 2 shows the amount of air per blower revolution the Weiand blowers pump.

TABLE 2: Supercharger Volumes
Supercharger Type Approximate CID or
Air Per Revolution
Pro-Street 142 142
Pro-Street 177 177
Pro-Street 256 256
Weiand 6-71 411
Weiand 8-71 436
Weiand 10-71 469
Weiand 12-71 497
Weiand 14-71 522
In selecting the proper supercharger for your application, you also need to take into consideration how you plan to drive your vehicle and the approximate boost level desired. How you plan to drive your vehicle is important because you can set up your blower to be more efficient at high engine speeds or more efficient at low engine speeds, or you can arrange for the best compromise for the full engine rpm range.
To run boost levels from 6 to 10 pounds we recommend the following:
Forged blower pistons with a static compression ratio of 7.5:1

• Steel crankshaft
• Four bolt main caps
• Steel harmonic dampener
• Stainless steel valves
• Three angle valve job
• More aggressive camshaft
• Roller rockers
• Ported and polished heads
• Steel rods with good rod bolts
• Chromoly push rods
• High output ignition
• Weiand high flow water pump (cast iron or aluminum available - see our complete water pump section for applications)
• Minimum of a 2-1/2" diameter dual exhaust with headers. Recommended primary tube diameters and collector sizes are:
• Small Blocks: 1-5/8" to 1-3/4" with 3" collectors
• Big Blocks: 1-7/8" to 2' with 3-1/2" collectors

For maximum boost and horsepower applications (12 pounds or more), we recommend the following engine specifications:

• High quality forged or billet crankshaft
• Four bolt main caps with quality bolts or studs
• Steel harmonic balancer or crank hub
• High quality steel rods (H or I beam)
• Forged blower pistons
• O-ringing the block (mandatory)
• Severe duty stainless steel valves or iconel
• Fully ported and polished heads
• Solid or roller cam designed for high boost
• Roller rockers
• Chromoly push rods
• High output ignition management system or magneto
• Blueprinted carburetors or fuel injection
• High octane race fuel (112+ rating)
• Minimum of a 3" diameter dual exhaust with free flowing street/race mufflers and large tube headers.
• Recommended primary tube diameters and collector sizes are:
• Small Blocks: 1-7/8" to 2" with 3-1/2" collectors Big Blocks: 2-1/8" to 2-1/4", with 4" collectors
• Maximum effective compression ratio on gas not to exceed 24:1
• It's important to realize that there are no hard and fast rules and the suggestions made here are general in nature.

an even better option in my opinion , requiring less hood clearance, would be a centrifugal supercharger with inter-cooler ( inter-cooler not shown in this picture) and a throttle body and direct port injection is also an option.

https://www.holley.com/products/int...MIgbncx6Cm3AIVFrbACh13kQbIEAQYBCABEgJwy_D_BwE

https://www.powerperformancenews.com/tech/grade-on-a-curve-choosing-the-right-supercharger/

http://www.superchargersonline.com/index.php?main_page=page&id=53

https://www.jegs.com/s/tech-article...chargers+-+Blowers+-+Roots+Type+-+Centrifugal

http://www.superchevy.com/how-to/engines-drivetrain/0610ch-superchargers/

https://www.carthrottle.com/post/what-do-supercharger-capacity-ratings-actually-mean/

 

[Speedlink1973]

Yep that's why I sent that 177 back
Because I didn't know what I was doing
Or getting into with it, and stuck to N/A
I've been eyeing that Holley EFI
One reason why is you can polish the hell out of it just above the injectors.

 

[Speedlink1973]

Math always looked good on Grumpy 496.
Build it.
Tune it.
Get the car dialed in.
See What it does.

So much torque just impossible to put down all on street tires.

I know this guy was mentioned
On here as a engine builder Mark Jones
I think my N/A motor will be in this area
Wish I had a good calculator to to see a curve.

 

[Indycars]

Wish I had a good calculator to to see a curve.

If you are willing to supply the input data, then I can run several simulations with DynoSim5.
Not the cheapest or most expensive software.

DynoSim5 Input Variables

Bore & Stroke:
Rod Length:
Heads with flow numbers:
Combustion Chamber Size in CC’s:
Dome Volume: For a domed piston use a (-) negative number. For a piston with valve reliefs use a + positive number.
Valve Reliefs Volume:
Deck Clearance:
Head Gasket Bore:
Head Gasket Thichness:
Valve Sizes I/E:
Intake Manifold Model Type [Single or Dual Plane]
Model #:
Carburetor Size (CFM):
SCR & DCR:Header Tube Diameter: Small, Medium, Large (1-5/8", or , or)
Cam Card:
Cam Installed per Cam Card, or Retarded or Advanced:
Rocker Ratio:
.

 

[Speedlink1973]

Oh I have another question for you guy's
I seen some of the blocks screens in lifter valley, I noticed some are screwed down and some that appear to have epoxy

If you are willing to supply the input data, then I can run several simulations with DynoSim5.
Not the cheapest or most expensive software.

DynoSim5 Input Variables

Bore & Stroke:
Rod Length:
Heads with flow numbers:
Combustion Chamber Size in CC’s:
Dome Volume: For a domed piston use a (-) negative number. For a piston with valve reliefs use a + positive number.
Valve Reliefs Volume:
Deck Clearance:
Head Gasket Bore:
Head Gasket Thichness:
Valve Sizes I/E:
Intake Manifold Model Type [Single or Dual Plane]
Model #:
Carburetor Size (CFM):
SCR & DCR:Header Tube Diameter: Small, Medium, Large (1-5/8", or , or)
Cam Card:
Cam Installed per Cam Card, or Retarded or Advanced:
Rocker Ratio:
.

This is what my virtual dyno pro app came up with
2" diameter tubes 37" long

The pistons are 25cc dome piston
But cc them in cylinder came to 24.4cc
But to take in account of big bore gasket diameter I lose 3cc so it's 21.4 cc as picture shows
Cam in at 108 center line retarded-4 degrees
Oh head gasket diameter is 4.540
Thanks
Injectors are 62lbs an hour 8 injectors total.

The throttle body injection works differently then a carburetor as far as cfm
Goes it's 850cfm but this will support up to 800 hp when I talked to Fitech about injectors at 62lbs an hour should support 950 hp or better, they told me the software is the limiting factor 850hp max
On pump gas , throttle body cfm is exactly the same as the 1200hp unit they sell
Not sure if your calculator can decipher
It or not if not I would use the recommended 1250cfm.

It would be interesting to see a couple of different curves being I'm using a adjustable belt drive and can adjust on the fly this app has me retarding it 4 degrees

I'm running a MSD digital 6AL MSD Pro-Billet Distributor
Not sure if you need that information or not.

 

[Speedlink1973]

Hey Grumpy, epoxied
A 13 lbs pull neodymium rare earth magnets in pan as suggested to pick up trash.

 

[Grumpy]

Hey Grumpy, epoxied
A 13 lbs pull neodymium rare earth magnets in pan as suggested to pick up trash.

I hope you bought thee correct high heat versions?
the next time you pull the engine down youll see all the crap they collected
http://garage.grumpysperformance.com/index.php?threads/magnets.120/#post-76617

 

[Maniacmechanic1]

Oh I have another question for you guy's
I seen some of the blocks screens in lifter valley, I noticed some are screwed down and some that appear to have epoxy

This is what my virtual dyno pro app came up with
2" diameter tubes 37" long

The pistons are 25cc dome piston
But cc them in cylinder came to 24.4cc
But to take in account of big bore gasket diameter I lose 3cc so it's 21.4 cc as picture shows
Cam in at 108 center line retarded-4 degrees

Thanks

Cam specs are mild for such a Big Ci. Engine.
Will make Superb torque.
Not a Supercharger cam . Lobe centers too tight.
Ok for Nitrous a small shot 125-150 .

What I see.