Hi, I have searched for this info, but I need more advice and help with this. We have built lots of 350's before, but this is the first 383. Here is what we have:

1985 Camaro
5 speed with 2.95 first and .67 overdrive
8.5" 10 bolt, 4.11:1 spool, adjustable lowers, may change to 3.73

We are trying to use as much of the old 350 as possible. It had stock rods, but good forged high compression pistons (unsure of brand). The engine was around 11.5:1, and ran good.

70 something 4 bolt bored .040"
New Scat 383 crank from Ebay
Would like to use the pistons, but not sure if pin height will let us.
2.02 Iron GM heads, mild port and polish, crossover filled
Harland Sharp 1.6 roller rockers and guideplates
Intake was a Weind Team G high rise
Very worked over Quadrajet, would like to use

I would like advise on SOLID cam recommendations, and where I can get cam, lifters, springs, locks all in one package. Advise on rod length, what I need to measure on my pistons to see if they work, and clearences on complete setup, oiling suggestions. Also header tube size and where I can find a set.

This car will be a daily driver, please keep that in mind with cam choice. Wants a fairly lopey idle, but need power at 2000 rpms. Engine probably won't see past 6200. ANy suggestions, changes, or parts findings are greatly appreciated.

Thanks,
Mike

As a daily driver, the first thing I'd sell is the spool! Not commuter friendly at all. Second would be the 11.5:1's. Something in the range of 9.5:1 will run on pump gas with a carburetor.

Cam choice is a black art. I'm running a Crane Crane Cams - #113821 (http://cranecams.com/?show=browseParts&lvl=3&prt=5&Vehicle_Type=Auto&Cylinders=8&Engine_Make=CHEVROLET&Year=1974&Engine_Size=262-400%20C.I.&partNumber=113801&partType=camshaft) and it performs as written. Good idle, good vacuum but it's probably on the light side for what you want.

typical 350 piston's compression hieght is about 1.565"
383 = 1.433 for 5.7inch rods.

according to my calculations (1.875+5.7+1.565=9.14) the piston will be .115" above the deck on a standard block. even with a .041 gasket you end up .074" above the gasket.

the only way to use the 350 pistons is to use 5.565 rods. (1.875+5.565+1.565= 9.005) which leaves the piston .02" down the bore in a stock deck block. but most people advise against using the 5.565 rods.

I'm running a Crane 278 solid cam in my 357, and it gives plenty of good torque from 2000 on up. It would give even more low-end torque with a 383 and the right compression ratio.

I'm thinking of using the same or a similar cam in my 383 build. I'm also going with a Scat 3.75" stroke crank, but I'm using six-inch rods and KB hyper dished pistons.

Your cam choice depends on your compression ratio. Once you're sure of what pistons you're using and what CC your combustion chambers are, you can pick a cam.

Or you can go the other way around and pick a cam, then choose your pistons and heads.

There's no way anyone can give a recommendation without all the info.

BTW, cute username. :rolleyes:

My first recommendation is to change your username, this is a family site and is rated "G" for General audiences, that means some of us sit and read the site with our children close by or reading over our shoulder. Nuff said about that.

We have a cam guru, designer and manufacturer that frequents this site, UDHarold from Lunati, he may see this post and reply. Good luck with your engine build.

Rusty, people dont want to use that short rod because of the bad side load on the pistons? Or is there something else?

Cjlandry, what more info do you need? I would like to use the pistons we already have, but according to the math, that will leave me with a real short rod. Is anyone else using that short of a rod?

John D, the dude only has to drive it about 6 miles one way to work, plus we are used to the spools, we like em. Will it make good hp/tq with that low of compression? Would like around 400 hp/ 450 ft lbs.

thanks so far guys,
mike

Mike,
First, assuming you could use the piston you have just changing the stroke to 3.75 is going to raise the compression almost 1 full point.
12.3 compression is not my idea of a daily driver. ;)
Scat has a few different 3.75 cranks, do you know which one you have?
The common one is for a 5.7" rod so you will not be able to use your pistons anyway.
As was stated earlier we need more input :D

And I have to agree with Leo on your choice of username, most of us don't really care about the linage of your ancestors & their are families that use this site smile.gif

The biggest problem with using the short rod has to do with the size of the counterweight on the crank hitting the bottom of your piston at BDC

I see. Well, I guess I am going to need pistons and rods now. Will I need a smaller base circle cam with the increased stroke, or is that jsut if I use H-Beam style rods?
The engine ran on pump gas before, that was another reason for the want to use those pistons. Again, talking a short trip for a DD, not far at all, so 93 octane is fine if that's what's needed.
I know of UD, I am into Oldsmobile's myself, have built many 11 sec. 455's and used his cams. Just new to the Chevy stroker thing, don't know any of the "stroker combo's". I know some of these questions might seem trivial to you guys, but we want this engine/car to be a good combination. Not overcammed, etc. etc.
mike

Mike, GM 2.02 heads isn't much info. What's the casting number on the heads? Have they been modified (shaved or chambers enlarged)? Are the pistons flat-tops, domes, dished? If domes or dished, what's the displacement of the dome or dish? How far down in the hole will the pistons be with those pistons and that stroke?

I'm sorry, but there's a lot more to building a stroker than using a crank with a longer stroke.

So you need to know what fuel you're using (89, 91, 93 octane?), where you want to make power (why only 2K with 4.11 gears?). Then you can choose a compression ratio or cam (one should be tailored to the other).

If you want an engine "recipe" using stock 350 pistons and a 3.75" stroke, I'd love to see someone provide something like that.

OK, so what crank did you get? You may be fine with the 350 rods if they're 5.7" and your crank is for 5.7" rods.

In that case, you still need to know the size of your combustion chambers to decide which pistons to go with. Keep the CR reasonable, then pick a cam based on that.

You're right on to want a solid cam. I ran hydraulics for years and switched to solid last year in my daily driver. I'll never go back. Better gas mileage, broader torque band, and more reliable (haven't heard of anyone wiping a solid lift cam). Mine pulls all the way to 6000 with my mild Crane cam.

I'm really looking forward to seeing what the 383 will do with a "real" solid cam (not something "off the shelf").

The casting numbers on the heads have been ground off. This engine was previously in a dirt track car, then sat for 3 yrs, then put into a 85 Gbody. Was pulled and taken apart after that. They have not been milled (or at least show no signs of it), and the chambers have not been modified. I just meant that they are regular old GM iron heads w/ 2.02 valves.

I could measure the piston pin height to be for sure if these will work without all the guessing. Also, they have a good sized dome with reliefs.
I can also get some more info on the crank in question.

Quote "I'm sorry, but there's alot more to building a stroker than using a crank with a longer stroke"
I heard that!!! graemlins/clonk.gif

Originally posted by High Output:
I see. Well, I guess I am going to need pistons and rods now. Will I need a smaller base circle cam with the increased stroke, or is that jsut if I use H-Beam style rods?
The engine ran on pump gas before, that was another reason for the want to use those pistons. Again, talking a short trip for a DD, not far at all, so 93 octane is fine if that's what's needed.
I know of UD, I am into Oldsmobile's myself, have built many 11 sec. 455's and used his cams. Just new to the Chevy stroker thing, don't know any of the "stroker combo's". I know some of these questions might seem trivial to you guys, but we want this engine/car to be a good combination. Not overcammed, etc. etc.
mike =
Mike,
Harold is at Lunati now but is on here quite frequently.
The H beam rods as well as the Scat I beam capscrew rods have more cam clearance than the stock rods & you will normally not need a small base circle cam depending on the grind.
You may need to grind the rods a bit at the corner where it gets close to the cam. You will need to do a little clearancing at the bottoms of the bores for rod bolt clearance where there is a small notch now. You just make it deeper. The pan rail sometimes needs a bit of attention for the counterweights. All this is no big deal.
I am guessing you have 64cc heads if your compression was actually 11.5 so you will not need anything but a flat top to get pretty good compression at zero deck. (about 11.0) Your pistons are not going to work with a 5.7 rod.
I have done quite a few of these & they are pretty straight forward,

There is nothing wrong with 5.565" rods in a daily driver. These rods are only .135" shorter than the 5.7" rods and nobody seems to have any problems with them . . . there is no real difference between the two rods in a fairly mild combo. If you are really gonna rev it then go with 6.0" rods.

The pistons though are another story. Like Wolfplace said your compression ratio will go up a full point if you were truly at 11.5:1 in the old motor. I bet you weren't -- unless you are sure they are domed pistons. A flat top piston will still make over 11:1 in a 383 which is a full point too much for an iron headed daily driver.

On the cam, I would seriously consider just going hydraulic FT. Since you are going to drive it DAILY I personally wouldn't want to hassel with checking lash every oil change. What about the Crane H272_H06 -- specs are 272* adv duration, 228* @ .050, 106* LSA, 102* ICL. It has a nice tight lobe separation (and would lope a little) but is still a fairly small cam --- should make awesome midrange power in a 383. Your compression should be down around 10.0:1 with this cam though.

Eric,
There is a problem with the short rod if he has a 5.7 Scat crank. The piston will not clear it ;)

Are your heads 76cc or 64cc? Either way, plan on changing pistons...there isn't any way around it. A flat top 2vr piston in a 388 (.060 over), with a 0 deck, 72cc heads, and a .038 head gasket is right around 10.3-1. This is what I have in my 388, and it runs fine on pump gas with a comp cams 294s solid, and has more than a little lope. It just starts to smooth out around 2K, but with 4.11's and a 3000+ stall convertor, is still pretty streetable. In a 388 it also makes just enough vac for power brakes. I have a scat cast steel crank, scat I-beam rods that are cam clearanced, and run a regular base circle cam with plenty of clearance.

Thanks for the help everyone, like I said I am new to the stroker thing. TOmarro morniing, I am going to check out the crank and pistons real close. I see most of these 383 kits use cast or hyper pistons?!? In my Olds world, as light as possible is best, even for a street machine. So it seems that the shorter rods are OK or not? I really want to stay with the Solid cam, trying to get as much power as cheap as possible, adjusting valves is kind of like the spool thing, just got used to it.
Thanks again

Adjusting valves? Man, this ain't 1969 no more (though I sometimes wish it were).

I've been running a solid cam for well over 14 months with only one or two adjustments the first month. I drive this thing 1500 miles a week! I get 21-22 miles per gallon on the highway, and I have all the low end grunt and top end speed I need!

I checked 'em religiously for the first 6 months, now it's just accepted that they're good unless they tell me otherwise.

No way I'll go back to hydraulic.

Solids are the way to go these days! The only way to get better is to go solid roller.

Yes, the short rod deal is ok as long as the piston clears the crank you have.
Last I checked, Scat does not make a crank that will work with the short rod.

I have built them all three ways (5.565, 5.7, 6")
& I prefer the 6" rod with the 6" crank as it makes it very easy to internal balance without problems.
As for power output, with all else equal & the right cam I doubt you will be able to measure the difference ;)

With a KB flat top and 64cc heads you'll have around 10.6 CR. KB has a 12cc dish too for about 9.6. All depends on deck height and chamber cc.

I'm running a 383, 6" rod, KB flat tops, and 62 cc vortec heads for 10.8 CR and a UD276/284F10 cam.
2K stall and 3.07's. Works fine. Could use a little more stall so it would idle in gear better, but it's not too bad.

I had to put the cam in at 110 ICL instead of 106 to get it to clear my clearanced cap screw rods. At 106 ICL, the ECL was 115 and hit #2 rod only IIRC. I have to run a 160 thermostat and 32 deg total timing and a cold air intake keep it from pinging.
I'm still tuning and just put the 160 back in. I might be able to run 34 total. It rattled pretty good with the 180 and 34 so I swapped both to make sure I stopped it. Now I can creap back up on it.
Well, after summer and the 100* temps hit at least.
It was only 82 the other day.

Your slightly lower compression might make up for my better chamber and allow you to run this cam.
OR you could get it ground with a 112 LSA. You might go to a 280/288F10. Looking at DeskTop Dyno, the 383 is kind've sensitive to LSA. Especially with smaller cams. There is a considerable difference between a 230ish hyd @ 114 vs 110 LSA in a 383. Just something to check into. YMMV

If I had your trans and gears(actually wish I did)
I'd probably go with the 280/288. Maybe @112 LSA to clean up the idle. Mine has about 11.5-12" at 900 rpm now w/the 276.

That's inetersting Mike . . . what is different with the Scat crank? Counterweights larger or placed differently? Does that apply to Eagle too? Could it be just certain pistons - like 350 pistons?

Originally posted by Eric68:
That's inetersting Mike . . . what is different with the Scat crank? Counterweights larger or placed differently? Does that apply to Eagle too? Could it be just certain pistons - like 350 pistons? =
Eric,
Exactly, the counterweight is larger in diameter so it has more weight.
This is the main reason why I like 6" rod 383 & 400's, it has enough counterweight so I can internalally balance them which is my preference if I can.

Scat has a numbering system that will tell you like 9-350-5700-2100 the 9 being cast, 350 main size, 5700 rod length, 2100 rod journal size.
First digit 4 is forged & 7 is their new custom crank line which is basicly any stroke,
Then thay also have a full line of custom billets for a "few" dollars more :D

I do not use Eagle cranks so I cannot comment on them ;)

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2466577858&category=33616

Ok, found out more about this crank. It was bought from this ebay auction, it does not seem to be a SCAT. Is this crank total junk, or will it work good for a street machine?

Also, I checked out the pistons. I am not seeing any markings or stampings on them anywhere for any kind of I.D.

The pin measures 1.570" from the top of the piston down to the center of the pin. That is the actual deck, not the dome.
It has a .250" popup with valve reliefs.
It measures 2.635" from the longest part of the skirt to the deck.
It measures 2.285" from the side of the skirt to the deck.
The piston skirt is .130" thick.
They are on stock rods that are 5.7" long

I guess I will just have to put it all togather with what is there and see if it hits or fits!!
any more ideas?
Thanks,
mike

Your missing a few things, 350 pistons will only fit a 3.75 stroke crank with 5.565 long 400 rods.
With 5.7" rods, you will need at a minimum, pistons for a 3.75 stroke and 5.7 rods. If it is originally a 6" rod crank, then 5.7 rods may, propably will, cause the pistons to hit the counter weights.
A 250 dome piston will not work on the street for a 383, so forget about using them. You need new pistons at a minimum, you may need new rods. A lot of the cheap cranks are poorly or not heat treated at all. SO THEY ARE SOFT on the bearing journals. Meaning they won't last a long time. So YMMV.

Mike,
No comment on the crank ;)
The actuall measurment should be 1.560 for your compression height which is the standard 350 pin height.
Again,,,your pistons & rods will not work with a 3.750 stroke & 5.7" rods & I highly doubt that crank will work with 400 rods.
This has been explained in a previous post but if you add 1/4 " stroke the piston is going to raise 1/8 " top & bottom.
Now if you are at zero deck to start with do the math.
Your piston is now 1/8 " ABOVE THE BLOCK at TDC & 1/8" closer to the crank at BDC.
Actually .135 above the block as your stroke is 3.48

Ok, so we have pistons and rods that won't work with our Junk crank!!! Welp, I guess maybe we'd be better off putting the 350 back togather with just a better cam.
Where can I find decent "kits", like the crank, rods, pistons, bearings, rings, to do a 383?

Originally posted by High Output:
Ok, so we have pistons and rods that won't work with our Junk crank!!! Welp, I guess maybe we'd be better off putting the 350 back togather with just a better cam.
Where can I find decent "kits", like the crank, rods, pistons, bearings, rings, to do a 383? =
Now,,,I didn't say the crank was junk ;)
I can't really comment as I haven't seen ony of them & don't have a clue where they are getting them but the price alone would worry me.
It costs more than that to get a decent grind.

If you are looking at Scat email me & I will see what I can do. I have pretty fair pricing on Scat stuff.

Originally posted by Scott_68_SS:
With a KB flat top and 64cc heads you'll have around 10.6 CR. KB has a 12cc dish too for about 9.6. All depends on deck height and chamber cc.

I'm running a 383, 6" rod, KB flat tops, and 62 cc vortec heads for 10.8 CR and a UD276/284F10 cam.
2K stall and 3.07's. Works fine. Could use a little more stall so it would idle in gear better, but it's not too bad.

I had to put the cam in at 110 ICL instead of 106 to get it to clear my clearanced cap screw rods. At 106 ICL, the ECL was 115 and hit #2 rod only IIRC. I have to run a 160 thermostat and 32 deg total timing and a cold air intake keep it from pinging.
I'm still tuning and just put the 160 back in. I might be able to run 34 total. It rattled pretty good with the 180 and 34 so I swapped both to make sure I stopped it. Now I can creap back up on it.
Well, after summer and the 100* temps hit at least.
It was only 82 the other day.

Your slightly lower compression might make up for my better chamber and allow you to run this cam.
OR you could get it ground with a 112 LSA. You might go to a 280/288F10. Looking at DeskTop Dyno, the 383 is kind've sensitive to LSA. Especially with smaller cams. There is a considerable difference between a 230ish hyd @ 114 vs 110 LSA in a 383. Just something to check into. YMMV

If I had your trans and gears(actually wish I did)
I'd probably go with the 280/288. Maybe @112 LSA to clean up the idle. Mine has about 11.5-12" at 900 rpm now w/the 276. =
Hi Scott,
I just read this post.
Just a suggestion for future reference as your engine is already together but with the capscrew rods you can grind them pretty good for cam clearance & this would be my choice rather than retarding the cam. Especially with Harold's cams.
They like 4-6 degrees advance & are pretty sensitive to retarding. You are probably leaving 10-15ft lbs & Hp on the table by running the cam straight up.
I could be wrong as I haven't used that cam & you might want to ask Harold but this is what I have seen on the dyno. ;)

The only problem I see with this in your case is if you are rattling now it will probably get worse with the earlier intake closing. :(
Also, Scat has a new 7/16" bolt I beam that has more cam clearance then the 3/8" one, it is profiled different. If you have ever seen an Oliver forged rod It looks a lot like that

i have the stroker-clearanced scat 6" I-beams with 7/16" capscrew rod-bolts.take it from me,they are a thing of beauty! graemlins/thumbsup.gif

High output, just a thought, and I also saw this 'misinformation " in the recent "Cam edition" of ChevyHiPo mag. Something like " frequent valve adjustments with a solid cam". I donnow, is once or twice a year frequent? FOr that 'hassle" you get like 5-10% more torque, smoother idle in a similar grind, etc.

Two EXCELLENT stroker cams mentioned above, the Lunati/UD 276/284, or the 280/88. 276/84 is a bit more agressive ramp. MUCHO POWER!

19Nova72 has a low buck stroker in his Nova I will pass this along to him maybe he can reply. I almost think he has that same Ebay crank. He used stock 5.5 400 rods and some 350 flat top pistons. He has some stock iron heads with 1.72 valves and home porting. He just ran a 13.35@101mph (fuel problems),(ran a 13.43@105 pass before) yesterday with a 268xe cam stock stall and street tires. graemlins/thumbsup.gif Not too shabby for a mild cost effective engine.

Hey guys, I still need your advice and help. I have been away from this project for a little while and am about to start it back up. I have looked at alot of the 383's that most of you have built, and kinda looked for parts and such. It seems that most of these engines are not really deemed "HIGH performance", just a good street engine. It also seems that most use a cast or hyper piston, not forged. Why is that? For less assy. cost or just not needed in this street type application?
Are these engines that much better than a well built 355 as far as torque? Are the hp numbers the same?
If you took a 355 making 400hp/400ft.lbs and swapped in a 383 bottom end, what would the difference be and where?

I know you are probably tired of "383", but we are wondering if it is worth doing.

Thanks,
mike

Build one, and you'll never go back to a 350...they make that much difference.