I'm not 100% sure if I want to build anything but I'll ask anyway.

I have the chance to pick up a 383 summit block from a friend for cheap and I already pieced together a rotating assembly that will yield approximately 10:1 compression on 64cc heads.

How would you guys top a build like this? I've seen edelbrock's top end kit that produces 460hp/460tq on 9.5:1 on a 383. I want to keep it as streetable as possible, would like to keep the stall mild (under 2500). This will be going in a 3rd gen if I decide to build it.

 

keeping streetable and 2500 or less stall, thats fairly easy to do and still make good power.

try a 190-200 cc head and a cam in the mid high 220's duration at .050". As much lift as you can get. Is it a roller block? Should be easy 450+hp on motor and run low 12's. Abit more stall and gear onslicks it should go high 11's and still be streetable.

My 383 was nasty but very streetable despite how aggressive it sounded at idle. it would run fine on 2500 stall if I wanted that but I ran 3600. ran mid 11's. 195cc heads.

Keep it MAF with a 6E based tune and it wont be hard to tune at all if you stick with a EFI setup. I'd run the HSR for best bang for the buck, but a modded and ported big tube TPI setup can work as well, just need to limit the rpm abit more. Try a lower 220's duration cam.

Carb, keep it in a dual plane intake like RPM air gap or similar.

 

So achieving 1.2 HP/CI isn't bad for a street car? I'm pretty sure the summit blocks are rollers but don't quote me.
I'm pretty sure Edelbrock's package is building power at just a tad bit over factory stall.

 

THere's no such thing as a "383 block". A 383 is built using a 350 block.

Of all possible approaches, the Edlebrock "kit" might be the worst. The heads are OK; they're absolutely not the "most power" heads out there, but work VERY well in a street-only or very limited racing setup where the purpose is fun and not necessarily winning. Their carbs are just re-badged Carters, and their cams SUCK. The intake is the only truly superior piece in the kit. The kit as a whole might, maybe, produce whatever #s they advertise, if installed on a short block that's tweeeeeked to absolute perfection, and with every other detail about the build finessed to the ultimate; but in the REAL WORLD, expect about 30-40 HP less, and a street-hostile driveability situation besides. Just an altogether BAD choice.

I'd suggest Dart Pro 1 200 heads w 64cc chambers, with the 1.45" spring upgrade (Comp 987s); a Comp "503" cam http://www.summitracing.com/parts/CCA-08-503-8/; 1¾" headers; a Performer RPM intake; and a Holley carb. Consider the 0-6210 which is a 650 CFM spreadbore. You'll want the "Q-Jet" version of the Perf RPM if you go with the spreadbore carb.

 

Yeah, 1.2 hp/ci is very nice and streetable. IF you pay attention to detail and built it right, you COULD get 1.3-1.4 hp/ci and STILL drive it on pump gas, less than 2500 stall, and run 11's in the 1/4.

I have a friend running a pretty big cam on a 360" motor that drove fine on stock stall speed... Lazy down low but it ran fine. With 3600 stall its MUCH more fun but still streetable. Dont be afraid of more converter since with a 700r4. You can retain lockup and tune it so that it locks up early and maintains 1 to 1 ratio....no slip so it drives like stock. I did that with my 383. Off the lockup mode, it slipped a good bit but still driveable. 383 makes enough torque to move around a car so it wont need to slip much.

I daily drive my bolt on LS1 car with 3200 and could easily get away with more. My 4000 stall non lockup converter in my Th400 turbo car actually drives around BETTER than the previous 3600 lockup i had in my 383, and the 3200 in the ls1. Its a better converter and you get what you pay for. I paid 900 for it the first time and 300 to get it restalled since it wasnt doing what i wanted the first time around. The other converters go for 500-550 shipped. It all comes down to how well its spec'd out.

Other than that, 503 cam is a great cam like above said. Good match with the 200cc heads and dual plane. YOu could even do comps 230 deg cams and still drive on mild converter. Depends on how much power you want and how streetable is "streetable" to you because that varies from person to person.

Now those examples are EFI cars so low rpm driveability is abit better unless the carb is really good quality and tuned well.

 

Summit has pre-machined stroker blocks. They are like $600-700 new, they are remanufactered blocks from the vortec trucks I think.

Thanks for the advice guys.

 

Right: they are 350 blocks, with a little bit of machine work done to them. THey are still 350 blocks. You might more correctly call them "383-ready" 350 blocks.

They are

and not

But that's not all that big of a deal, it's just wise to know what you're REALLY dealing with.

Note that I called out for a roller cam, expecting that either the 350 block in question came with the factory roller apparatus. If you're using the original design roller setup, you can't really use the off-the-shelf cam (well, you could but it would be more of a pain and expense than the alternative), you'll need to have them custom grind that profile onto an original style roller cam core, starting with "12-" instead of "08-". Have them use a billet core if you go that route.

 

I'm well aware what a 383 is. It was just easier to say. I finally took a look at it, it is a roller block. I think I'm going to buy it and go with some AFR 195's.

 

If I decide to go with AFR 195's best case scenario from their "suggested" street setup (which I will probably just copy since it's on a 2500 stall) is 503 HP / 517 TQ I think. As far as bottom end goes, will this work:
http://www.coasthigh.com/Chevy-383-D...45-sf-c383.htm

If I am to upgrade to plasma moly rings, would the bottom end support the extra power?

 

18cc dish is too much. In a 383 with 64cc heads and the usual .045" of deck clearance that you get with replacement pistons, your CR will be about 8.9:1. NOWHERE NEAR ENOUGH to get any 500ish HP out of it.

Since the link doesn't work (times out with an error after about 5 minutes) I have no clue what it's referencing.

However: I'd suggest something like this http://www.summitracing.com/parts/ESP-B13052L030/ http://www.eaglerod.com/index.php?op...d=21&Itemid=32 which if the block is "zero-decked" (VERY IMPORTANT) to the pistons, will give you about 9.8ish:1 CR. That, plus the cam suggested above or maybe one slightly larger depending on what induction system you're intending to run, should get you a pretty good bit of fun, for a street car.

 

I havent looked up the summit blocks, are they 1 piece rear main? I imagine they are based on the roller block requirement.

Flat top piston and 65cc AFR's is what I ran and gave 10.9 to 1 compression or so. With my big cam it was very loud with a single 4" exhaust and I'd estimate it was up around 500hp. Streetable and got decent mileage but it was loud with all the compression...I found it hard to tame down the noise with a single exhaust muffler. 9.8 to 1 can work well but I'd try a 10-12cc dish if you can find them and shoot for low 10's to 1 with the aluminum heads. Should be a fun motor and run on any gas you want if you tune it for low octane.

 

I ended up buying the block.

I probably won't be building this until around July but here's what I've been looking at, I've upped my limits to a 3-3,500 stall. Give me some opinions!
- Probe rods/crank/Flat Tops -4cc coming out to what I calculated at 10.6:1 compression
- Comp Cams K12-460-8
Adv. Duration 304/304, Lift .600/.600 (too large for my application and street use?)

Good starting point? Which heads would be better, AFR 195 Competitions or AFR 210 Competitions?
195s (2nd flow chart):
http://www.airflowresearch.com/index.php?cPath=24_29
210s (2nd flow chart):
http://www.airflowresearch.com/index.php?cPath=24_33

Ideally I want to keep it a pump fuel motor and have it be streetable behind a 700R4 and I'll regear to whatever I need to... as long as I can drive the thing locally without it stalling I'm more than happy.

 

That cam is a monster but would work ok for a really aggressive 383. I had that sized exhaust lobe on my 383 but my intake lobe was much smaller. If you do that cam, I'd go 210's out of those choices if you want AFR's. Abit cheaper option would be to talk to Speier Racing heads and get his mild ported 210's for 1500 bucks. They will match anything the AFR will do and may even be better. Or you can just get the regular AFR street port and save 500 bucks. Either way you need to get a good valve spring to control those high rpms. AFR 8019 springs in their heads with small shims, or Chad Speier will find a good spring for his heads..probably a strong LSx style double spring like AFR's 8019 but also shimmed for more pressure. I ran the 8019's with abit of shimming to 165-170lbs on the seat and it didnt float a valve.

That cam will turn to 6500-6600 rpm peak hp and hold to 7K. That is a very aggressive street setup but CAN be tuned and streetable. -4cc flats should give just over 11 to 1 with 65cc chambers. 11.1 to 1 with 64cc chambers. Perfect for that cam.

You will need a good intake manifold to feed this thing. It will have to be a good single plane intake if going carbed. If EFI I'd recommend the victor E EFI single plane intake with elbow and LSx 90mm TB.

I have heard 700r4's dont like high rpm but I turned 7K on my setup for a little while and didnt hurt the fresh strong rebuild 700r4 I had. Not sure how long the life would have been tho.
I'd go atleast 3500 stall on this setup.


Now this build is abit different than your original post of streetable as possible and mild stall It will work out but it will be a loud powerful setup. Thats your 500+ hp build. LOW LOW 11 second 1/4 miles on typical street/strip chassis setup. With more stall and gear, and better chassis setup at 3400 lbs it could go high 10's at sealevel type conditions.

Abit more streetable/mild combo would be 2800 stall, 195cc heads, mid 10's to 1 compression, and ten or so degrees LESS duration on the cam. Probably a step or two down from the cam you have picked.

 

For my 2 cents. I like big cams, when they're put with the right combination. I would definitely go with the bigger heads. That cam would be a waste on anything smaller than 210 intakes. The single profile may be a bit much on those heads but with the CNC exhaust ports, matched up with big primary headers and large exhaust, you should be okay. With carb and Victor JR intake this will be a challenge on the street, but hey, for the flat out ***** it will have, I say it's worth a little clug a lug idling around town.

I hate high stall speeds on the street, but with that combo you don't have much choice. That motor will probably fall on it's face with anything under 3,500. If you have the money and time to play with it, you might try a 3,000 just to see if it will work. The better the converter, the better it will run. I like Hughes converters for the 700R4.

As far as high revs go, I run my 700R4 to 7,000rpm alot. I also worry about it just a little very time. And I make alot less power than you're talking about. You may end up wanting to step up to a 4L80E. The 4L80E is a completely different design and will handle the high revs and torque much better.

 

Hows that ZZx treating you with the 355? EFI I'm sure really helps the driveability.

 

alright well I'm hearing a few different opinions now. One guy seems to be on a difference stance then you two and he makes some very valid points. I guess I'll talk to my buddy's dad (he builds pro-street BBFs) and allow him to throw in his 2 cents as well.

 

The ZZX with my combo is very streetable. It has a bit of an idle but not unpleasant and even with 2,300 stall, it takes off any way you like. Clouds of tire smoke or smooth like pudding. Depending on my mood. LOL

 

Problem with that cam is, it pretty much REQUIRES a compression ratio that puts it out of pump gas range.

A little too much to bite off on, for a beginner type of street build. With good heads, you don't need so much cam anyway; power output is determined by cylinder fill at any given RPM, and if the heads are good then the cyls are 100% full, and holding the valves open farther and/or longer doesn't add any more power. The only reason to use a large cam with large heads is to turn LOTS of RPMs, which isn't consistent with a street build anyway. Best to err slightly to the small side on the cam, when paired with good heads.

 

Thats the thing, from your first post talking abotu a milder street build setup, we gave some insight on a milder setup. Then a few posts later you start talking about 10.6 to 1 comp, 3500 stall, AFR 210 heads and 244 deg cam... Good combo for a wicked street/strip setup...about as stout as you can build a hydraulic roller 383. Thats a completely different animal tho from your first post.

 

LOL. Its the lure of power. It's like a drug. Once you get started there's just never enough. The guy starts out thinking of a nice sunday driver, next thing you know he's building a pro street monster.

Same thing goes for guys who put twin turbos on small blocks. LOL. One guy got so carried away he cut holes in a pefectly good hood to clear the damn things. Oh, that's you! LOL. Face it we're all a little touched.

I dont know if I agree that this combo wouldn't work on pump gas. 10.6:1 with aluminum heads, on 92 octane, could work. Though being a carb setup is going to make tuning alot more difficult. Definitely, a slightly smaller cam(290degrees) would work just as well with the rest of the combo and make things much easier.

If this were going to be port injected then it's a different story. But wet flow, especially carbureted, it's gonna be real tricky.

 

LMAO thats right. I had a perfectly fine 10 second nitrous 383 that was low maintenance and a blast to drive...i go tearing the car apart. It never ends...lol

I think on 92 you could run that combo at that compression and cam. I had a smaller cam in a 11 to 1 motor with AFR heads and it ran fine on 93 with all kinds of timing and when running dangerously lean. It should work fine. But as said the carb tuning will make it or break it as far as streetability goes. EFI it will be fine.

 

EFI or carb shouldn't matter. You just have to know how to tune.
I don't see any trouble with a 10.6:1 aluminum headed 383 (carb or injected) on pump gas PROVIDED all the basic performance parameters are met. Timing. Temp. DCR.

 

[QUOTE=ASE doc;4788314]LOL. Its the lure of power. It's like a drug.QUOTE]

Isn't that the truth.

 

EFI to support that combo isn't cheap. It would have to be one of Edelbrock's port injection systems, based on the Victor Jr manifold, with the 1000cfm TB to provide enough air. Or maybe a similar unit from Holley.

 

[QUOTE=sofakingdom;4788208]Problem with that cam is, it pretty much REQUIRES a compression ratio that puts it out of pump gas range.QUOTE]

Interesting statement. While a huge cam requires lots of SCR to maintain and build compression pressure, isn't it that same compression pressure that mandates the use of one type of fuel over another? If DCRs are within pump gas limits, then what does it matter? Use pump gas.
I would think it's more the INTENTION of the build. If I'm going to use a cam with loads of duration and have a 13:1 SCR to support it, I would say I'm building a dedicated race engine so race gas it will be.
To support sofa's statement (not that he needs support), don't build into race engine territory if it's not really a race only engine.

 

So I just got to thinking and I have no idea if it's right or wrong but if I were to keep this 10.6:1 compression and run a cam with a larger exhaust duration and lift; would it "bleed down" some of the compression?

I think as soon as I finish freshening up my big block it's getting sold to help budget this build. I've assembled motors before, never anything on such a large budget so I don't exactly trust myself building this alone. I will probably have my neighbor build it with me. As far as tuning it, it's going to a local performance shop that deals strictly with carbed race cars. I'll talk to him before I buy the heads or bottom end just to make sure he's confident he can tune it on pump fuel.

 

IF you increase exhaust duration and make no other changes you increase the cam overlap and it will bleed off compression, at lower rpms. It should have lower cranking compression I think.

Dynamic compression isnt the end all be all value to determine if it will run on pump gas or not. Its a good target but not always true because some motors are capable of developing more than 100% VE, which means they will fill the cylinder with more volume than what the dynamic compression calcs will say is possible. So the effective compression is higher than dynamic and is the pressure that really matters. Since most street strip bolt together motors arent really seeing much more than 100% VE anyway, there is no real worry. A great designed motor can have as much as 115% VE naturally aspirated!!

I"m pretty confident that you could run that motor on pump gas at 10.6 to 1. Like i said, i ran 11 to 1 with less cam than that. Dynamic calulated at 8.3 to 1 and it was fine.

i think you could cut back on the cam and keep those heads and a single plane and still get great hp and be a good bit more streetable. I think 195's and a 230 deg cam would also make great strong hp and be abit more streetable with a carb.

 

Oh alright, thanks for clearing that up.

As far as what I want to build, I think I'll have to really think it over. I'm leaning towards sacrificing a large majority of "street manners" to have the extra power but I'm not sure yet.

 

You can have your cake and eat it to if you pick the right components. A great quality carb in the hands of a skilled tuner will make that combo work with just about any combination of cam/head. Its not necessarily cheap but worth it. You can go abit less head and cam than those 210's and that magnum grind, and still make mid 11 second power. Thats a fast street car

 

The reduced compression pressure from a large cam can largely be atributed to the later intake valve closing. Changing the exhaust duration will have little to no effect on the cranking pressure (despite the change in overlap).
That said, the increased intake charge from an engine with a high VE (Orr) adds to the race fuel arguement. And so on.
I would think you might be very happy with a 1.2 hp/ci pump gas 383 that you can drive every day.

 

Yeah thats right, I knew the exhaust duration didnt change intake closing point which is used in dynamic compression but wasnt sure if increased overlap changed any part of the cranking compression cycle or not. I think it does change the ability for lower rpm cylinder fill, which is just VE at lower speeds.

 

I've understood that an earlier exhaust opening (all else being the same) is used in a nitrous application so as to allow more time for the larger volume of spent combustion gases to escape. If you follow this further it also increases overlap (as suggested) and you get all the benefits/holdbacks that go along with it.

 

If this is your daily driver, don't go too far toward "race car".

The fun goes away IN A HURRY when you have to depend on a gas-sucking, parts-breaking, nightmare of a maintenance headache that your SO won't even get into because it's noisy, smelly, scary, and unreliable, for transportation to and from your method of paying for it; and it consumes SO MUCH money keeping it going (and trust me on that, IT WILL), that you have NONE left over for anything else.

Sure, speed sounds tremendously attractive, when you don't have any. But too much is just about as bad, especially when you have no experience with how much WORK and MONEY it is to keep it going. Err on the side of caution.

 

This isn't a daily driver, yes it will be driven a lot in the summer but I have two trucks I drive around so if this were to break it wouldn't be a big deal.

 

Sounds like an interesting topic for a new thread.
Where is the boundary between daily driver/street strip/race car? I'm sure the responses would be many and varied.

 

I think if some can get it to idle with vacuum, there are a few guys here I bet will call it a street car.

 

Streetability is a relative term. It's really just a question of your tastes. The balance between good manners and power is a compromise. It's up to you do decide which is more important.