Dorian’s Big Block C3 build

In other words a bullet proof, regular pump gas, 12.5 sec, 9:1 compression 496 BBC. That starts, runs, drives and stops like a much newer Corvette.

yeah! we can do that

Sarcasm???? o_Oo_Oo_O

I think we all see where I am going... reasonable 1/4 mile is whatever is left on the table after fulfilling the first bullet points:
- TBI
- Excellent idle
- Excellent street manners (not to come across as sexist but a lady should be able to drive it)
- Durability and reliability

"starts, runs, drives and stops like a much newer Corvette" rather, it should not scare the crap out of my wife with pig-like handling and stopping. Smooth idle (with TBI) so she's not afraid it will crap out at every stoplight.:cool:

Whatever 496 we can build to reach that (it should be easy!) :D

Suspension, stopping, etc. I'll build something out of that...
 
Sarcasm???? o_Oo_Oo_O

Ira, no way! Never thought that.

I believe I was just about on,the money.

450 to 500 hp is an easy goal for Any presision built BBC with decent internals and I don't think it needs more than 9 to 9.25 compression. With such compression I see little need to worry about high octane fuel.
With a possible change over to Rack and pinion, new suspension and new brakes, wouldn't this car then be like driving a much newer Corvette?
450 hp, doesn't that equate to a very easy 12 sec. in the 1/4 mile?

I rest my case LOL!
 
autowiz said:
Grumpy you are certainly right custom building an engine can usually bring you to a much lower price for a build. But I can get 1,000hp out of a crate LSX right now for $15k. Maybe less. Out of a 6.2L. And it can hold a butter smooth idle. And it can get good gas mileage when your foots not in it. With the boost ready LSX376 and a pd blower. With all the defected lsa cores selling on ebay so cheap, I might be able to bring that figure down as low as 13k or even 12. And that is with a crate engine and not doing a damn thing to it but swapping the intake manifold and pinning the crank so the balancer doesn't slip.

Prices for LS stuff was high 10 years ago. Today it is LT that commands a premium and there is absolutely no good reason to swap anything but LS, LQ, or LSX unless you have the money for LT. I know I am gonna be vilified by a lot for these claims. It is just an observation from being so deep in building so many. It is what everybody wants. To create the same level of control system on an old sbc or bbc pushes the cost of such a build WAY over what an ls setup with harness and controller would cost. And I am not talking about that toy efi carb replacement junk, either. I mean a real controller that measures crankshaft speed in between ignition events and records the differences in camshaft and crankshaft variances from timing component slack. I am talking about linking the ignition timing to a pair of sensitive knock sensors, And timing the fuel injector pulse to the opening of each valve on a given cylinder so the fuel doesn't pool up on top of the valve and cook waiting for it to open. Sequential fuel injection. And the only way to get it is with a cam and crankshaft position sensor. There is one solution to put a cam and crank sensor on a sbc or bbc and this timing cover, sensors, cam sprocket and crank reluctor is, well, it is this:
https://www.eficonnection.com/home/...-signal-kits/efi-58x-product-line/efi-58x-bbc
And that is just to create the proper input signal for a good controller. It will take thousands of dollars to apply an LS level control solution to an older engine platform. The cost of doing these conversions is more attractive for an LS. We are coming up on the end of 2016. The LS engine family is 20 years old now.
My claim of 1,000hp for $15k is this engine:
http://www.chevrolet.com/performance/crate-engines/lsx-376-b15.html
And this blower:
http://www.vortechsuperchargers.com/page.php?id=45123
And then you would want to add an intercooler and some extra piping and a good tune and a 3 bar map sensor.


yes theres no question that if you have the cash available you can supercharge an LS series engine and get impressive power levels,
I'm fairly sure many of the guys reading through this don,t or have not dealt with, or built enough engines, and been involved with enough of the engine builds to realize the various manufacturers approach building components with a great many different objectives in mind,
component parts vary and careful research and selection is required!
I've always found SCAT and CROWER parts seem to be a good value!
keep in mind the "weakest link in the chain" concept,
Any logical engine builder needs to sellect components with a firm goal in mind and recognize the intended power band and rpm limitations.
need there's not much sense in selecting a rotating assembly that is built to easily handle lets say 1200 hp and 7800 rpm, at 4500 fpm in piston speeds,
if the block main caps walk at much lower stress levels, or if the block your thinking of using it in,will most likely have the caps walk well below that stress level.
nore would it make sense, using such a high dollar rotating assembly if your going to match it with a valve train and hydraulic roller cam that floats valves at 6400 rpm, or heads that reach port stall at 6700 rpm
thats really not in question,
or DORIANLs goal in this case,and you can obviously spend a good deal of cash on a big block chevy and still use its greater displacement to build simply stupid amounts of horse power.
we can build a very streetable 496 big block that works with power brakes, runs on pump high test gas and still has very impressive power on tap without the typical tendency of many high performance engines to be a P.I.T.A., and over heat and studder when used at lower rpms, nor will it need to reve to 4500 rpm to start producing impressive power levels while still maintaining its ease of driveability.
any decent big block build starts with some basic research into what the goals are and in this case ease of drive-ability ,instantly accessible power,and good vacuum brakes, trumps peak horse power as the intended goal, but that does not mean it has to be a wimpy combo....far from it!


personally ID point out that the cylinder heads and cam selection will be critical here, I could easily suggest a bit more cam duratio and lift and boost hp 50 pls hp, but at the cost of a slight lowering of easy street manors
AFR make an excellent street performance oval port cylinder head made for this type of build

HEADS

http://www.airflowresearch.com/265cc-bbc-oval-port-cylinder-head/
CAM
http://www.claysmithcams.com/bbc-454-to-470-cid-old-school-oem-049-781-heads-to-a-max-of-5700-rpm/
LIFTERS
https://www.summitracing.com/parts/hrs-91167

a decent 496 short block, with 4 bolt main caps and a good 7 quart baffled oil pan that fits a c3 corvette that does not extend more than 8" below the block would help,a combo like this will be easy to drive if you don,t put your foot on the accellerator and push it firmly to the floor.
SHORT BLOCK

http://www.jegs.com/i/Blueprint+Eng...208630350311&gclid=CK7Jp7_ytM8CFcImhgodu_EA4A

COMP PRODUCTS DART SHORT BLOCK ASSEMBLIES
http://www.competitionproducts.com/Short-Blocks-Chev-BB/products/1611/


matched to a hydraulic roller cam like this one above, and some thing semi reasonable in rear gear ratio, like a 3.54:1 -3.73:1 rear gear ratio and a decent manual transmission and a 32lb-35 lb billet steel flywheel , a low restriction exhaust, headers, a dual plane intake like this
INTAKE

https://www.summitracing.com/parts/edl-7561/overview/
and a decent carb, personally if it was my corvette Id sellect one of the new 750 demon carbs as they will easilly feed the 496 bbc in its intended rpm range and they don,t cost an arm & a leg.
CARB

https://www.summitracing.com/parts/dem-1904

http://www.jegs.com/instructions/132/Demon.html
roller rockers will help
https://www.summitracing.com/parts/csp-s2012
selecting a good single plane intake , instead of that dual plane, will kill off some low speed torque but pay off in a noticeable boost in power over 5000 rpm
INTAKE OPTIONAL

https://www.summitracing.com/parts/wnd-7620
keep in mind this is a valid option as you may not want massive torque early in the rpm range as it will make someone with a heavy foot easily spin the tires while the single plane intake produces more peak power its a bit softer in the lower rpm band, neither choice will be weak, either way youll be impressed if you give it a bit of throttle, but your sure to feel a difference.
especially if at a later date you swap to a cam with a bit more duration, that also moves the torque curve higher
be aware that Most performance intake manifold designs require the big block hood which has a couple more inches of hood clearance vs the sbc corvette hood on the c3 corvettes ans early c3 corvettes hoods are not directly interchangeable with the later c3 hoods
http://www.corvettestoreonline.com/...68-1972.html?gclid=CNaZ9YG3wM8CFUqTfgodqTUOgw
http://www.ecklerscorvette.com/corvette-hood-long-style-l88-1968-1972.html
you can calculate the compression with the 109cc head chambers and a head gasket of your choice (try to keep quench in the .040-.044 range and I think youll find the compression in the 9:1-9.6:1 RANGE.. with a decent radiator and a 7 quart baffled oil pan I doubt youll have any chance of detonation issues )
Aluminum water pump

https://www.summitracing.com/parts/edl-8850
road race oil pan
https://www.cantonracingproducts.com/product/15-320/15-320----BBC-STREET-T-PAN/

http://www.csgnetwork.com/compcalc.html
 
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well an thoughts, complaints or questions?
any progress getting a project car etc.
keep in mind that c3 corvette once correctly set up will be miles ahead of that TT in handling even with a big bock,
in fact I doubt youll see any difference in handling compared to a SBC powered version of the same car once you get proper tires and suspension components
 
I THINK IT MIGHT HELP IF THERES SOME RELATIVE CONTEXT IN THE LEVEL OF HANDLING THAT THE OWNER IS USED TOO OR REQUIRES.
Dorian previously own a 600 hp supercharged SBC mid 70s chevelle , and correctly set up c3 corvette will be worlds ahead of that cars road handling , I,ve driven several friends big block c3 road race corvettes, and owned a 1968 BIG BLOCK and 1976 SBC corvette, theres no
way you can expect too compare the handling potential of that mid 80s chevelle with a properly set up c3 corvette, they successfully raced 427 L88 big block corvettes at sebring and other tracks and were very competitive, at racing some of the best cars ever built
his goal is to build a nice looking, even, impressive looking, dependable performance car his wife and kids can drive as occasional transportation in Europe, not to build a race car!
l88p4.jpg


to maximize hood clearance on the 1970 bbc chevelle and some rectangle port bbc engines in corvettes they used a special low rise intake design
BTW heres the factory extra low profile rectangular port intake, while it provides good hood clearance its easily costing you 20 plus horse power over several similar low profile intakes , and easily 30 less than many high rise intake designs


ls6m1.jpg

ls6m2.jpg

ls6m3.jpg
 
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Greetings folks. Sorry, I got a little snowed under here.

IMG_4144.JPG

You could say things are getting a bit busy here.

Yes, Grumpy, I have an excellent lead on a clean C3. The seller is on busier side so it might take a few weeks for things to start moving. o_O Things are looking good, tho.

The Chevelle was a 73! I boxed the lower arms, 100% polyurethane, HD antisway bars from and rear, fast TA steering box, QA-1 shocks. Everything I could do, I did. I suppose it was all right. I was expecting the Ghia (1971) to be better, and nimble but it wasn't really.

So I guess I want something that handles better than both! It doesn't need to handle like a new sports car, but I want something that has reasonable ability.

The 496 you describe seems spot on! Thanks. I can start saving for that

I'm looking forward to building a proper vintage sports car.

BTW, the TT dynoed in the high 600s. ;-)
 
This construction interests me. What all is going on?

Btw, my first procedure starts tomorrow, lots of tests and questions and the second procedure is on the 7th, I hope this crazy thing works!
 
Heh! My Chevelle parking only sign is still up...

I am getting the rotten gutters fixed and the roof tiles replaced. There are no leaks... but the moss is eating away at the tiles. Lifting them. Since we extended our loan to pay for all new doors and windows (done) and a new fireplace... it was time to do roof, gutters and balconies...

Then I'll rebuild the kitchen, the office and the cloakroom o_O

The new fireplace with build in speakers was supposed to start getting installed today... but the scaffolding seems to be in the way and it insert weighs 800lbs :eek: Nothing in life is easy...
 
So, are you getting a wood burning or gas insert to your fireplace? Wow! 800 lbs is got to be the largest insert I ever heard of! I understand in Germany and surrounding countries have laws about heater and fireplace efficiency and testing is done on some sort of scheduled basis. Do you guys have licensed chimney sweeps for required cleanings for both heater flues and fireplaces?
 
That's a nice looking house, how old is it? That's some serious union company scaffolding, I'll bet it has some really nice wood floors too! Sorry, had to go off topic, Home renovations have always captured my attention, I was in many different things of contruction up to and through the early years of my college years.
 
Yes. The house was built in 1907 about. There is no official record. It is classified as a manor. It belonged to the railway and is where they housed the station master. In the time before cars :eek: train station master was a VIP. The house originally had four chimneys and six fireplaces. No central heating here :rolleyes:. I'm
Restoring one fireplace. It has 100-year-old hard wood floors, yes. And lots of other features. It'll be a real fireplace and the installer will come and clean it once a year as a service.
 
I see you have an insulated liner. From the size pipe it looks like this is a wood burner but I thought your part of the world had moved away from wood and was burning gas or pellets?
 
This is purely to have an open fire. Making pizza, roasting marshmallows and the snap, crackle and pop. A luxury. The central heating is perfectly adequate
 
Those little holes in the wall are the speaker apertures... they are high quality James Loudspeaker units. I had them built in. They'll be driven by a Bluesound Powenode. NAD technology and engineering. Only wifi lossless streaming from Tidal.
 
Our last house had a fireplace in every room, this on has 2 crappy gas fireplaces and chimnies just fo looks #thissucks
 
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