I'm rebuilding the '65 350
 

...to a 383 stroker.
I had a little mishap and instead of driving (limping) around with a patch job to the rod bearing from underneath, I decided to open her up and see what's what and drive her the way she's supposed to be driven! It'll be a 383 stroker after all is said and done!
These are the parts I will be using. I'd like opinions as to what cam will work with these. OK, so far I have:

Muncie M21 with 4.11's in rear

Holley 4bbl model 4150 list 4779-9 750 DP (rebuilding to over 750cfm by a pal) using a Holley Red label electric fuel pump (universal)

Edelbrock C3BX dual plane aluminum intake manifold (replacing the old Torker single plane)

J&C assembled hi performance aluminum heads; 64cc, 190cc runners, 2.02/1.60 valves, .600 valve springs, str8 plugs.

The rebuilder will be supplying the 400 crankshaft (not forged)

They'll be boring the 350cid block .030 over to make it a 383 (don't know if it's been done before)l. I'll presume that the block is acceptable and 4 bolt! Theyll have to inspect before we proceed. They're very good people to work with and told me they would work with me for whatever I wanted.

They will also supply a cam that they feel would work best with that set up. Before I get this done, I researched the cam threads and read alot of good stuff on cams but can't quite put my finger on the right one yet. They are suggestion Lunati, and I've heard of the L79's that I've read good reports about. Elgin is also in the running. Remember, to save funds, I am using the parts as above so what I'm paying for at this time is the new cam, new crank, machine shop work, and labor to put it together.

Also I'll be asking for forged flat top pistons unless they talk me into dished to prevent high compression detonation with what they want to use for cam

So, what would YOU do? I appreciate all you guys' help :lurk:

I'd get rid of the double pumper carb first off.

Use the 5.7 length 350 rods.

I'd keep the compression around actual 10.5. I'm not a fan of dropping compression any lower than necessary.

The cylinder head people could make a good recommendation for a camshaft that's compatible with the heads. Take into account what type of exhaust system you'll be running.

I don't think you'll need to pay for the forged pistons. Use hyperuetectic unless you have good reason to use the forged.

Oh yeah, I forgot to mention the exhaust. I'll be using the current Hooker headers with side pipes. They are serviceable and I don't need to pay for extra stuff. What's the difference between forged and hypereutectic?

I can't give you tech advice, but I can tell you one thing. GET IT ALL IN WRITING! We have seen and heard our small share of engine shop miscues here on the forum and the anguish they create....you don't want that! :cheers: Dennis

I'm not sure of how you''ll use you car when you finish. These would be my comments on how I would have rebuilt mine, and then I spent more time and money, to get it to the point it is now. I wish someone had told me the following.

The rear end your running will only be enjoyable in town. If you are thinking of driving long distance or on a highway anywhere, the engine rpms will drive you nuts.

I kept my 3.70's but installed a 5-speed and now have both worlds.

Dennis

OCS, I have thought about that because I have driven for 2 hours straight and the noise did start to get to me. But I won't do that so often, but I do plan to race at the drags every so often, so the 4.11's will stay (and I enjoy it on the street too). I have also thought about 5 speed, but the tranny is good right now and just the engine needs work, so for now, that's all I have fundage for.
Bluestripe, that's good advise and I ALWAYS get things in writing, no matter what. Thanks.
MikeM, I emailed the head people and will wait for their response. I chose forged just for strength since I'll be drag racing too. Why lose the DP?

The hypereutectic pistons are not as strong as a forging, typically have different expansion rates than a forging due to the alloys used, and are not the best if you intend to hammer the engine hard. For just cruising and the occasional "put-your-foot-in-the-kitchen', they will be fine and save you some coin.

Sounds like a sound build so far. With the money you are spending why not spend a little more and get a full roller set up? The heads you have selected are good heads and would be well used with a good sized roller cam. Also there is nothing wrong with a DP. I have been running BG SD 650 and 750 on my motor with no problems. The 650 is now on my father's ZZ4 motor. No choke on either of them.

Don't let them talk you into a high volume oil pump a stock Melling 55 will be just fine. With you being in Kalifornia are you sure you want to run 10.5 compression? I can get good gas here in NC and still only built mine to 10 to 1 with aluminium heads. Did I leave some on the table sure but how much 5-10 hp and I don't have to worry about finding gas.

Is there a reason that you want to go with the C3BX manifold vs the RPM Performer? You didn't mention what rods or pistons that you are going with. I would be suspect of the old rods that are in there. How about what timing gear set are you going with?

Make sure that they discuss with you how much they will be boring the cylinders as well as how much the will be taking off the deck. Once they let you know how far you are in the hole ask what head gasket thickness they will be going with so you KNOW what your compression will be.

We can't wait to hear more about your motor!!! Trust me the Forum loves spending other peoples money....

:lol: Ain't it the truth. Its so easy :lol:

It looks like you have some decent parts to work with. The 4 spd, 4.11 gears,a nd 190 CC heads look like a decent match.

I would recommend going with forged pistons, simply because I do not know anyone with a 4 spd, 4.11 gears, and aluminum heads that aren't out there beating on their car.

I would also consider a vacuum secondary carb, rather than a 750 double pumper. You'll see better drvability and a few more MPG. I would look for a carb in the 650 CFM range.

Regarding your choice of intake, is there any particular reason you are going with a C3B? I would think the Torker would be a better match for your 4.11 gears and 190 CC heads. I second Hitch's suggestion for an Edelbrock Performer RPM. You can even drill it for an oil fill tube if you desire.

I am currently running an unported C3B on my dished-piston 383. This is a relatively low-buck engine I originally built for my truck, nothing special. With a mild HR cam, and a 3.36 posi, my 62 Vette went 12.64 @ 107.97 on 11/22/08 at Famoso Raceway. The C3B has poor fuel distribution, and I have some plugs reading rich, a couple reading lean, and some that look about right. On the chassis dyno, power fell off at 5000 RPM with the C3B.

Your 190 heads probably take a 1205 gasket. The Torker intake could be opened up to a 1205 Felpro, and ported through its full length. A guy I race with is trapping at 118 MPH in the 1/4 through a ported Torker.

Given the issues with modern oil and flat tappet cams, I would consider an HR cam. The HR cam will boost your torque and throttle response. I went with a mild HR, and our car idles like a kitten, but violent wheelspin is just a blip of the throttle away...

Hi guys. Thanks for all the great responses! The Edelbrock C3B"X" was given to me by a friend, and since it's double plane (and free), and I mostly drive the streets and occassionally drag race, thought it would be a better fit at mid range rpms. I can always replace with the Torker if I miss it.
I want to use the same LT1 valve covers that are on currently so I'll stick with the standard set up rather than full rollers.
I am going with forged pistons (new since the block is getting bored out .030)
For some reason that I can't put my finger on, I like my Holley DP and will still use it for now, especially since I already have it. I'll just get it rebuilt and cut off the choke housing for better airflow. May go to around 800cfm. If gas goes up again then I'll consider a vacuum secondary for economy (if that word is in the Corvette dictionary).
I'll look into the HR cams. I remember reading about them previously (I thought they were rollers).
I will be keeping the rest of the car stock, so it will have to handle whatever is placed in the engine compartment, so it has to be conservative but to the maximun limits. I don't want you guys spending my money buying driveshafts, race slicks, suspension parts and general beefing up toys for a pro setup. I just want her to kick more arse than before!:lol:

Lets take this from the top.. 800 CFM is WAY to much for what you are discussing. 650 Okay 750 OKAY.. 800 NO..

The full roller will fit under stock valve covers no problems especially with the AFR heads. The only thing you have to do is make sure you don't get the tall poly locks. We can definitely spend money but not on the things you mention. I think that like Wes, Myself, Brian and others we only want you to think of the whole engine not individual parts that you want.
Dave

Thanks Dave. I am thinking of the whole engine, and the parts that I have already are going to be the whole engine. I just don't have the cam to go with yet. Bear with me now, why is 800cfm way too much? Way too much what? I thought the cfm means airflow, so that's not bad, is it? Unless that much airflow disrupts something in the carb or intake that I haven't read about yet. If it's too high, then I'll leave the choke housing and blade on and leave it at 750, but I need a reason since I'm not mechanically inclined. I need something to make me say hmmm.
BTW, your current avatar is better than your cat one :lol:

OK dokk, here goes. (jees, do i have to do all the math for you...:willy::rofl:)
convert CI to CF 12"x12"x12"=1728 CI=1CF
383 CI=.2216 CF
the engine is going to have 3000 intake strokes at 6000 RPM (4 stroke engine)
.2216CF x 3000=664.8 CFM of airflow.

on your carb you are mistaken, removing the choke housing will NOT increase airflow, that is a function of the diameter of the venturies. removing the choke housing just eleminates a possible restriction between the top of the choke housing and the air cleaner lid.

EDIT--theres your hmmm.
it is a well known fact that you can gain a little more HP by going slightly larger that the 665 CFM airflow required (this 665 CFM is calculated at 100% VE).
now your carb is a little large but since you already have it-go with it.
also, with those heads-unless you are going to do the chamber mods i described (i figure NOT), with a 383 CI build consider pistons with a small dish the keep the CR on the safe side (remember mine calced out at 10.71 without the chamber mods, that's a little high-:ack:)

hey wes, no offence intended, but i'm the guy who gave dokk the C3BX manifold. if i thought there was anything wrong with it i would not even have offered it to him (it would make me look bad-:rofl:) i ran that manifold on my 64-fuelie heads, 30-30 cam with the hookers he has and the fuel mix was dead even. all the plugs always came out with that light brown on the insulators and if i mixed them up nobody could one spark plug from another. i think you may have had a carb problem. while i don't remember racing any vettes back in the old days, i did race a lot of big block chevelles and super sports and beat the snot out of them with that C3BX manifold on my car. so does anybody know what the X stands for on the C3BX manifold??? :lurk: could it be experimental??

I'm not much on aftermarket parts but I'm thinking the "3" in CB3 stood for the center divider being cut out to use a three barrel Holley carb. Yeah, I know. Some of you never heard of a three barrel.

Also, the fact this engine is going to be used as a driver instead of a thrasher is why I suggested the hyper pistons. True, they're not as strong as forged but they're much stronger than cast pistons. They're okay to use in nitrous engines. Why not in a driver engine and save money? New design forged pistons may fit tighter. Don't know. The ones I'm familiar with fit around .005 clearance and are noisy. Doesn't bother me. I like the sound but others may not.

Same with the cam. If you want the thing to sound period correct, get a flat tappet cam. If you want it to sound "funny" get the roller. If sound doesn't matter to you, dis-regard the previous.

One more time. The static compression you can run will depend on several factors. One key factor is the camshaft you intend to run. Pick the camshaft and then shop for the compression.

You need to do your due dilligence before selecting heads and pistons. So many builders throw a bunch or parts together in the hopes that a good enigne will be born. Before your selections are made you need to tear down the engine and take measurements.

Also, I huge carb may give you some incremental power at high RPM but it will make your car difficult to drive as it will not respond well to changes in the throttle. Think about it, if adding HP was a simple as adding CFM, everyone would be driving around with 1000 CFM carbs.

Too big a carb will give you sluggish throttle response off-idle. Unless you spin the engine to 8,000 RPM you won't be able to use that much flow anyway.

Mechron, no offense taken. I don't claim to be an expert. I don't question your motive for giving the intake to Astrodokk. I ran the C3B because I wanted an old school intake, and I wanted a breather so I could run closed valve covers.

The following are my experience and observations.

I pay pretty close attention to my car and tune. In May, I drove the car to Kentucky and back with the same carb and a Weiand #8120 dual plane intake. Plugs all looked good. On October 20, 2008 I raced my car, with the old stroked 327 engine and the Weiand 8120 dual plane intake. Drove 125 miles each way to the track, and the plugs looked good. I went back to the track the following weekend and ran a Weiand Team G. Plugs all looked good. The Team G was worth a few hundredths in ET and .5 MPH.

When I went to the track on 11/22/08, I drove, as before. This time, the car had my trucks 383, instead of the stroked 327 (with a re-ground F/T cam and doo-dah #461X heads).

The fresh 383 had a mild HR cam (.492/.501", 224/232* @ .050", 271/280* adv on a 112* LS). Plugs were fouled upon arrival at the track, and again upon inspection after the first pass.

FWIW, the stroked 327, with the Weiand dual plane idles with 18" of vacuum. With the Team G intake, the stroked 327 idled with 16.5" vacuum. The 383, with a milder cam and the C3B idles with only 16" of vacuum. On the chassis dyno, the engine went rich at upper RPM, but it wasn't rich in the lower revs. We dropped the secondaries 4 jet sizes, and power improved by 4 HP, and torque dropped 3 ft lbs to 446 ft llbs @ 2700 RPM. The fuel curve was still a little fat up top.I didn't get to do any other tuning, because there were other cars in line to be tested.

At least in my experience, the C3B was capable of allowing a 12.64 ET, with a 5000 RPM shift point (limited by my A/T trans being left in D). That was a decent E/T, all things considered. I smoked a few BB Chevelles with the old 327, but haven't raced any yet with the 383. I did thoroughly wax a new SRT8, though.

The unequal fuel distribution was my experience with the C3B. Your mileage may vary. :cheers:

Wes

Hey, Carlos,

I agree with the other folks - IMHO anything bigger than 600CFM on a street car tends to be overkill. Now, that's not to say that the 800 CFM DP that you have doesn't run well, but you may enjoy improved drivability with something smaller.

Swapping a carb is a relatively easy task...maybe you can borrow one from someone and try it out, see how it runs - and make your own decision based on driving experience.

Just my 2 cents; your mileage may vary.

PS I have a Holley 600CFM single pump with vacuum secondaries & electric choke - send me a PM if you're interested.