I looked for years trying to find my idea of a hot rod, as everyone has their opinion, and finally located the the foundation in a 1931 Ford Tudor. Its looks the part but I still want to change a lot including the engine and transmision for starters. I always like the SBC 327 and found a block that did require a 30 over bore. Then picked up a set of virgin 461 heads. Now the plan was to use the original cast crank because it not really for racing but more for the right sound and look. I did have it balanced with aluminum flat top pistions and .487 lift cam. On the heads I had 2.02 aluminum valves, roller rockers with screw in studs. Then to top it off i installed a tri-power. I know with out a dyno it would only be guessing but could anyone esitmate the HP of this simple little sbc? Next I wanted a 4 speed so i picked up a muncie M20. It needs a complete rebuild and I am wondering if there are options for gears or do you just rebuild it back to factory specs? DOes any one know of a good location for the the rebulid kit? Lastly, with this basic information what gears should i run on the street for reasonable performance?
I am not familiar with the heads, but the intake combination will also have an effect. You should be able to tune out about 325 - 400 hp maybe and the ****** should offer a 1:1 final drive. The car will be pretty light, so more of a highway gear would still accelerate pretty good, so I would guess a 3.0 to 3.27 gear if you are looking for decent acceleration and still want some mileage, and if you want to lean more towards mileage then go even taller on the gear (lower numerically). A few questions that might also help... How much do you think this will weigh when finished? What intake/carb are you planning to run? What exhaust?
Call me tomorrow at 972-495-1557 at Sachse Rod Shop,and i'll give you guys number on going thru the ******.I would'nt go over 3:50 gear ratio.Ask for Wayne
I think it should go about 1900 lbs based on what i been told. The tri-power is an eldelbrock aluminum with 3 rodchesters and progressive linkage. Ceramic hugger headers.
I agree...you'll be right around 325 to 350 or so. What compression are you running? With the close chambered heads I'd imagine that without a dished piston you'll be close to 10:1 or higher...
want old school get rid of the block hugger ,go try y full lingth, or ram horns, but most of all have fun jim
You can pick up 2 1/2" Rams Horn exhaust manifolds from Speedway for $59 each..an awesome deal! They won't restrict your setup at all and will flow as well as most headers while looking on topic and cool and NEVER leaking.
325 Hp should be obtainable (@the crank)if the blocks not decked and you use the 4 eybrow flat tops comp with be close to 9 to 1 and will run on pump gas The 1900 sounds optimistic though Id guess more like 2300 LBS.
461's are closed chambered heads...used in high compression applications. As far as I've ever known you need dished pistons or thicker head gaskets or both to bring the compression down below 10:1...
Check Autogear for Muncie parts. If you have to replace a bunch, you're probably better off buying a brand new trans. They sell them complete for about $1800 w/new case, gears, steel midplate and lots of upgrades. That's what I'm putting behind my 327.
We're looking at 9 to 9.5 to 1 on compression. Was hoping for a bit more HP though. But with a light car it should be plenty.
Anything above 300hp will be plenty for that car. Had a 70 Nova SS with 350/300 and Muncie for a long time and it was fast as hell. Probably at least 50% heavier than what your car is going to weigh. I am putting my 327 in a '32 coupe. I have a forged crank, **** I-beam rods and that's about it right now. Will probably go with forged pistons and a Comp Cams Nostaglia grind cam. I'm planning to run a 4-barrel (maybe a spread-bore Holley 6210) on a dual plane intake with the Corvette rams horn type exhaust. Haven't decided on rear gear yet, but it will probably be low 3s because I plan to do a lot of highway driving. But I will probably have a separate 3rd member with 4.11s that I can drop in when I want to take it to the track.
My mistake, your right. the factory weight was 2375 but with the hot rod updates I imagine closer to 2500. The block was decked and I am using the 4 eyebrow pistons. Still hope the comp is below 10:1. Just looking the a rocking lope at idle and a nice strong pull of the line. I agree the Ram's horn are a great old school look but I guess in this case i'm sticking with the cermaic hugger's. Thanks for the lead on Muncie parts. Just doesn't seem like a hot rod with a one of those little 4 speeds.
Like everybody else said low 3s gear should be find for you. And i have a 1931 Ford Tudor with SBC/TH350 and it weighs around 2900-3000. It's full fendered and I think that was with me in it
Your little coupe should fly. Can i ask the reason for the 4 barrel choice? I know my tri-power is costly but the look of those duces bring back lots of memories. They still flow at about 650 cfm so should bring decent performance. What is the lift on that Comp cam?
Wow, thats a lot heavier that i thought. I am running gl*** fenders and running boards but if that what you got then i'll be pretty close. I think i am going ot go weigh in and see. Shouldn't matter but just for my own info.
Yeah mine has steel fenders and running boards that should be the only difference. And I believe the Rochester 2Gs flow around 280 CFM a piece which would be roughly 840 for all three open. Good luck it should run fine
I would run the numbers to measure "uncorrected" chamber volume / compression ratio (many places to find a "how to" on the internet). The reason it is called uncorrected is because pistons expand and engine dynamics change while running, hot, and at different RPM's. If you can, have a shop give you more accurate CR numbers. Although I completely understand your optimism, I'm still thinking you're going to be close to 10:1 just because of the nature of the components you listed. You will be OK with pump gas at around 9.75:1 MAX...so don't lose heart if the numbers are high. You can also run a thicker head gasket (as long as you use performance application gaskets) to reduce CR, but I wuldn't do that until you know you're approaching 10:1 for sure. Here's why I mention this: I'm running closed chamber heads with flat top pistons and I'm at 10.25:1... You're better safe than sorry...
I'm going to use a 4 bbl because that's the simplest, most reliable and best performing setup. I intend to drive this car on a lot of long trips, like Chicago to LA, etc. and need to be able to fix or replace parts anywhere I happen to break down. For the cam, Comp Cams has a number of Nostalgia grinds and they even have reproductions of the Duntov cams and stuff like that. I'm going to see what they recommend for my setup and then see if my machine shop/engine builder concurs. Since this is going to be a highway car, I'm not looking for a radical grind.
Im curious as to exactly what pistons and heads your running to get that compression with flat tops? Using several online calculators mine is about 9.0 with my combo 4.030 bore 3.250 stroke Speed pro forged flat top 4 eyebrow pistons -7 cc's .023 down the hole .039 head gasket 461 heads 66 cc's Im guessing on chamber volume here because they have 2.02 intakes added and unshrouding them plus the dished valves as oppsed to the flat stock valves I figured probably adds 4 cc's genebrownlow, as for your rear gear I'm running a muncie as well with a 3.42 gear guessing my truck is about 2900 wet with me in it. the 3.42 works out really well I can cruise at 70 -75 all day and its not too bad in town driving either with the 2.54 first gear
OK, obviously I have to SHOW you because you don't believe me: Basic/unbored double hump small journal 327 setup: Cylinder head Volume (CC) = 62.00 Piston Top Volume (CC) = -4 (valve relief) Cylinder Bore (Inches) = 4 Cylinder Stroke (Inches) = 3.25 Deck Height / Clearance (Inches) = 0.000 Head Gasket Thickness (Inches) = 0.040 Computed Compression Ratio is 10.26442231 to 1 Bored .030 over: Computed Compression Ratio is 10.3935197624 to 1 So, unless your gaskets are at least .070 thick or thicker and/or your pistons are BELOW the deck you won't get below 10:1...period. BTW: the EXACT math on yours comes out to 8.90667838 to 1...just so you know... Now, to be fair the pistons I have I believe are -5cc, but my gaskets are only .030 and my block is .040 over Also, I could be wrong on stock piston volume, but I do know that my block was rated at 10.25:1 from the factory. Bottom line, there is a pretty big difference between your 327 and my 327.
This is my 30 Model A, 327 .30 over, 9.25 cr, 3 deuces, comp cam, 280 dur., and its a 480 lift with 4 speed.
I think everyone needs to keep in mind that there were more than a dozen stock configurations for the 327 and that there are at least 100 different ways to build one.
Geez Buzz , I didnt say I didnt believe you. I asked what pistons and heads you used to get that much more compression than my combo! I guess I should have asked if yours was zero decked because you didnt mention that in your post and since he said his was bored but said nothing about it being decked . I had to ***ume like every other 327 I've had apart with aftermarket flat tops (thats not decked) the piston is at least .020 or more down the hole. your first post could be kind of misleading - "With the close chambered heads I'd imagine that without a dished piston you'll be close to 10:1 or higher..." and again in your next post -"461's are closed chambered heads...used in high compression applications. As far as I've ever known you need dished pistons or thicker head gaskets or both to bring the compression down below 10:1... I was just trying to clarify for Genebrownlow if his block was'nt decked he should be ok using similar pistons to mine if you would have said on a zero decked block you will be close to 10 to 1 or higher I wouldnt have even mentioned it. More than a few of the aftermarket flat top 327 pistons are rated below 10 to 1 compression with 64 cc heads Genebrownlow if your deck has been cut to zero piston/deck clearance you are gonna be a bit high on compression Just like Buzznutt said but it might not be the end of the world, choosing a cam that bleeds off some compression with overlap could help make it better. Or a thicker head gasket to lower compression could help (But Im not a big fan of large quench areas sometimes it can hurt as much as it helps on detonation) but thats an option too or sell or swap your humper heads for some 76 cc heads will for sure help. Maybe it wasnt decked much and wont raise the compression as much as you think. do you know how much it was decked?
Russco, I said that tongue-in-cheek...just razzzin you a bit, I'm not that much of an ahole. I should have been more clear about the fact that my plugs weren't below the deck.
Pardon the hijack, and the fact that I'm green when it comes to building sb chevys, but all this talk about 461's and higher than 10:1 compression has me wondering if I f'd up by buying 461 heads today. I bought a set today for my '66 C10 which has a stock 327 and currently does not have double hump heads. Can I run the 461's with my stock pistons? Will I need thicker head gaskets with stock pistons? If so, what thickness? Where can I get the thicker gaskets?
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