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Topic Review (Newest First)
01-25-2019 05:19 PM
arnoldsel
Update?

So what did you do? I like the LS with a Pro Charger or the cheapest type of those blower. With an LS you can get the computer of which you can also tune for these blower. Had a 97 Vette and also a 350 Vortec Head Built to similar horsepower. Sorry the LS is such a better engine. No leaks and just a better smoother engine. I am really looking at a change to one some day.
09-13-2018 03:27 PM
64nailhead
Quote:
Originally Posted by '48 Austin View Post
I'd put in an LS motor and be done with it. The sky is the limit on power and they last.
And when they don't, another 4.8 or 5.3 is $300 away. Add a cam and springs + the boosted things - it's so hard to turn down. The OP hasn't revisited, but his plan with an SHP 400+ cube build at 10 psi makes 500hp seem almost free (to me). Once you get the past the cost of his long block and $1000 of TB EFI stuff, he would be wondering why he never did this before.
09-13-2018 01:08 PM
'48 Austin I'd put in an LS motor and be done with it. The sky is the limit on power and they last.
09-13-2018 07:11 AM
cerial [QUOTE=tyler2you;4600250]


- 80/20 street/strip with good street manners
- Strong torque from 2500 to 4500. Thinking something in the 500 lb ft/500 hp range. Don't want to have to spin it over 6000
- Solid reliability/longevity
- Can run on 91 octane

A stock late 60's early 70's Cadillac 472/500 checks those boxes. Need to run 93 due to compression, do some head work, timing chain, recurved hei, and a few other things. But out the gate your talking 300/450ft lbs in a high nickle block weighing between a 350 and 454 with stock heads.

I would find a entire rusted car and use the th400 or maybe manual valve body 4l80. Give the motor a mild rebuild and run a newer carb or self learning efi.
09-12-2018 07:19 PM
MouseFink 400” bore x 3.00” stroke = 302 cu. in.

This engine was a proven winner at SCCA races

In 1962-1964 I had a 1956 Chevrolet with a 1958 block which was bored to a 302 CI engine. Three speed transmission and overdrive. It was one of the best runners i have ever had.
09-12-2018 06:22 PM
Hot Rod Todd I ran a mild 454 with a 671 and made 627hp and got 13mpg on a trip in a heavy bucket (2500 lbs) with 3.0 rear gears. Ran low 10s on the quarter on pumpgas.

A mate with a way lighter bucket and a wild 350 ran 10.6 on the quarter - he probably weighed a good 500lbs less than my car, so probably a bit over 500hp. His engine really needed a lot of revs to get to its power band.

Both cars were street driven a lot, and raced over summer. He took mine for a drive once and commented how it had heaps of low down torque and you didnt have to rev it to move along quickly.

My motor was a 2 bolt 454 with cast crank - got it double key way'd. I got the factory rods shot peined, and from Summit I got some TRW forged blower pistons (about US $600) and a Comp Cams hydraulic flat tappet blower cam (about US$300). I changed the stock heads for some second hand alloy Bow Ties and including the second hand 671 and the new ignition, the whole deal cost me around US$5500.

So under US$9 per horsepower. I thought that was great value.

I have seen big inch SBC engines that (over here) cost over US$40,000 that make around 800hp so thats US$50 per horsepower.

Blowers can be cheap horsepower.

Keys to making them work on a budget is good low comp forged blower pistons, double keyway the crank, and fit a decent ignition system. Forged everythings are great if your budget can handle it - my next engine was a blown 540 with new everything and that cost about US$20,000 and made 851 hp so US$23 per horsepower.
06-26-2018 10:01 PM
vinniekq2 If you stick with the mono leaf?
50/50 rear shocks
traction bars need to bolt to the spring mount plate(not clip ons). The traction bars may need to be lengthened, The snubber must at least reach the spring eye. The right side snubber should be preloaded to touch spring eye and left side about 1/2" clearance. Sub frames must be tied. Rear end will need a positive axle retention system.
If you follow a good recipe I can see low 11s easy
06-26-2018 09:38 AM
tyler2you
Quote:
Originally Posted by vinniekq2 View Post
You need to PM Richard 9Techinspector) He can help you with the back 1/2 of the car. A 500 hp engine in a "Shakey" II is a dis aster to drive with out serious front and rear mods. If all chassis work is done then all is good,,,

Good points. I put in a MII IFS (TCI) up front, but have the single mono leafs in the back with a Ford 8 inch and traction bars. I've been looking at subframe connectors and an independent rear set-up with a Ford 9 inch, but the price is pretty steep.
06-26-2018 08:15 AM
vinniekq2 You need to PM Richard 9Techinspector) He can help you with the back 1/2 of the car. A 500 hp engine in a "Shakey" II is a dis aster to drive with out serious front and rear mods. If all chassis work is done then all is good,,,
06-26-2018 07:58 AM
tyler2you
Quote:
Originally Posted by vinniekq2 View Post
I don't see your math?

I gave up on the detailed math after looking at the cost of doing a Vortech/Procharger or Weiand blower and a forged lower end. I would also want to upgrade my ignition to something electronically controlled. It starts to add up quick for supercharging. I'm sure turbo can be done a lot more economically, but I'm not looking to do that much custom fabrication.


I agree that it's probably smart to limit the cubes to 440 or maybe 427 to allow room for a rebuild down the road.
06-26-2018 06:34 AM
vinniekq2 I don't see your math?
build engine "X" amount?

build engine "X" amount plus "X" amount for boost

build 421 cube N/A engine about the same hp about the same price
note original question about best "stroke" for a large small block

the 454 may or may not have issues with head gaskets and there is no room for over bore.
build a 440 cube if you want to use all of the bore you can and still be able to rebuild

If you absolutely must have the biggest small block? Then use a talldeck and go 472. Gonna get expensive,,,

Im not familiar with "Blueprint" brand blocks/cranks/rods?
06-25-2018 05:32 PM
tyler2you I've been reading up on supercharging/turbocharging and the more research I do, the more I think something like this might be a better option for me:

https://blueprintengines.com/collect...cts/gm-454-ps2

563 HP / 545 FT LBS with a 30 month/50,000 mile warranty. I'd be interested in seeing the dyno plot to see where this thing makes power. Only drawback is I'd have to save my pennies for a while and couldn't piece it together a little bit at a time.

I see so many cases where someone makes a mistake with timing, fuel ratio, or gets some bad gas and does permanent damage with a boosted platform. The NA approach just seems to be a lower risk approach, albeit at a higher cost per HP.
06-23-2018 03:26 PM
tyler2you
Quote:
Originally Posted by techinspector1 View Post
I was just thinking that if you lived anywhere near a diesel muffler or exhaust shop, they would have all the equipment and expertise to fabricate and weld up the whole mess for you.
Funny you mention that. We had a great muffler/exhaust shop in town up until about a year and a half ago. The guy retired and left us with a few Midas shops and one mom and pop place that thinks 2 and a quarter inch pipes are huge and can kink and bend turns with the best of them.
06-23-2018 02:52 PM
techinspector1
Quote:
Originally Posted by tyler2you View Post
Jim--thanks for the advice. The turbo approach does look appealing, but it appears it would take quite a bit of custom fab work to get it done on my car.
I was just thinking that if you lived anywhere near a diesel muffler or exhaust shop, they would have all the equipment and expertise to fabricate and weld up the whole mess for you.
06-23-2018 05:49 AM
tyler2you Jim--thanks for the advice. The turbo approach does look appealing, but it appears it would take quite a bit of custom fab work to get it done on my car. Heck, it was hard enough finding a set of long tube headers for it that actually fit without bashing for the pan kickout, starter, steering, etc.

I like the idea of the Weiand Pro Street 177 blower as it looks like it could fit under my cowl hood and I see several builds on the net where folks are adding 6-9 psi of boost for 80-250 HP. It appears most of them are running 93 octane when the boost gets above 6 psi with a base 8 or 9 to 1 compression ratio. At 9 psi and above, it looks like race gas is required.

Looks like I need to put together a spreadsheet and lay out the costs for a few setups.
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