# I finally decided on which size engine to build.



## NYH1 (Feb 3, 2010)

I've been hemming and hawing for the last few months on whether to build a 350 or a 383 for my Camaro. Well over the weekend I ordered THIS rotating assembly. My piston and rings are .040" over though. Summit had to order it from Scat. They had everything in stock and are going to drop ship it right to me.

When I dropped my block off at my machinists, I planned on building a 350 (355, .030" over). My block ended up being no good. My machinist had the same casting number block. He pretty much gave me the block and only charged me for the machine work and the parts. 

It was cleaned, magna fluxed, bored and plate honed, the decks were decked at 9.010", the mains were align honed. He installed new cam bearings and freeze plugs. He also tapped the oil galley holes at the front (under the timing cover) and rear of the block, the one down on the oil filter housing and the one that's under the head close to the oil sending unit. He installed pipe plugs in all of them instead of the cheesy little plugs the factory uses.

When I picked the block up, my machinist and I talked a little more about what I was going to do with the block. I needed all new parts for the short block. I told him I was going to order a balanced Eagle rotating assembly. He told me that he's had a few problems with Eagle's products and highly recommended that I go with a Scat rotating assembly instead. He also said to have it balanced locally. The guy that does all his balancing is supposed to be very good. 

So I figured that since I was going with Scat parts that cost a little more then the Eagle parts, I might just as well go with a 383 stroker.  At this point, there wasn't much of a difference in price between building a 350 or a 383 stroker. I went with 6 inch rods (which cost the same as 5.7" rods) so I could use my factory internally balanced harmonic balancer and flex plate. So if anyone asks.....it's just a 350! 

I'm going to go with Vortec heads. He has a few sets as cores. We just have to see which casting numbers he has so I get what I need, which is one of the two different L31 350/5.7L heads and not the L30 305/5.0L heads. If he doesn't have a set I like I can buy a brand new set of assembled Summit Vortec heads for $630. RHS has some really good prices on their Vortec bare heads. I'd still have to buy valve, springs, retainers, keeper locks.

I'm going to end up with a two bolt main, 385 CID small block. The displacement is from the 400 SBC size 3.75" stroke crank and the 350 block
being bored .040" over making the cylinder bore diameter 4.040". 

I've read a lot on 383 stroker motors with Vortec heads. They all say that together they make a lot of low end torque. More then likely, I'm going to use a Edelbrock Performer RPM intake. I'm leaning towards a Edelbrock 650 AVS carburetor or a Summit 750 vac. sec carburetor. I've used an Edelbrock carb before. The Summit carbs just came out last year I think.

If I built a 350, I was going to use a Edelbrock Performer EPS intake. Since I'm building a 385, now I'm leaning towards a Performer RPM intake because of the added displacement. I'm not going to turn the motor any more then 5800/6000 RPM. Edelbrock recommended I go with their regular Vortec RPM intake and not the Air Gap Vortec RPM intake. I'm going to be driving this car in Temperatures from 40°/45°F in early spring and late fall, to 90°/95° in the summer months. Because of the low Temperatures I'll be operating it in, they said my carb could be to cool when it's colder out.

With the forged 18.6cc dished pistons that come in my kit, I'll have 9.47:1 static and 7.16/6.83 dynamic compression ratios. Depending on which cam I go with will determine the dynamic compression ratio. 

I'm looking at a few Comp Cams flat tappet cams. Two hydraulic and two solids. A hydraulic would be easier. Pretty much set the correct preload on the lifters and you'll most likely never mess with them again. However, I like the solid lifters with the oil hole in the center of them. It puts pressurized oil right on the lifter/cam contact point.

Hydraulic- 
XE262H 218/224 dur. @ .050", .462/.469 lift, 110° LSA, 1300-5600 RPM. 
XE268H 224/230 dur. @ .050", .477/.480 lift, 110° LSA, 1600-5800 RPM.

Solid-
XS256S 218/224 dur. @ .050", .465/.477 lift, 110° LSA, 1000-5600 RPM.
XS262S 224/230 dur. @ .050", .477/.488 lift, 110° LSA, 1300-5800 RPM.


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## Den69RS96 (Feb 4, 2010)

Glad to hear its going well. Sounds like a nice set up. Keep the rpms under 6500 and keep the hp under 500 with the 2 bolt mains and your motor will live a long life. Wonder why your macine shop did not convert your block to 4 bolt mains. Did your machine shop install ARP studs for the mains? Just curious as they provide a little extra insurance against cap walk.


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## 04ultra (Feb 4, 2010)

Did you ever consider a crate motor ..........Lots of really nice packages .....







.


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## NYH1 (Feb 4, 2010)

Den69RS96 said:


> Glad to hear its going well. Sounds like a nice set up. Keep the rpms under 6500 and keep the hp under 500 with the 2 bolt mains and your motor will live a long life. Wonder why your macine shop did not convert your block to 4 bolt mains. Did your machine shop install ARP studs for the mains? Just curious as they provide a little extra insurance against cap walk.


My max RPM will 5800-6000, when I install a MSD 6AL box I'll chip it at 6000 RPM. As far as power, I'm hoping to make an honest 350 HP and 425 FT. LBS. of torque. 

If I found a good 4 bolt block for a good price I would have bought one. However for my projected power level my machinist didn't feel the need was there to install 4 bolt caps on this block. We went with ARP main bolts though.


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## NYH1 (Feb 4, 2010)

04ultra said:


> Did you ever consider a crate motor ..........Lots of really nice packages .....
> 
> 
> 
> ...


No, I like building my own engines. I really enjoy it. Plus I know exactly what I have. 

On another forum, a guy bought a GMPP 454 HO. It ran like crap, he ended up tearing it down. GMPP wasn't that helpful either. Not all the push rods were the same length.  The only thing I could think went wrong was that they did a model "change over" right around the time they assembled his engine and all the parts weren't changed out. If GMPP will make a mistake like that, I'd hate to see what could happen at one of the smaller places out there. My best friend has had horrible luck with his GMPP ZZ4 engine. I don't want no part of that.


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## cuznguido (Feb 9, 2010)

It is your money, but if I was going to go with a 383 i would scour the earth until i found a 400 block and do it right. You will be happier in the long run. Stroking the 350 block to get those cubes requires some pretty serious compromises that end up costing big $$$$$$ sometimes.


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## NYH1 (Feb 10, 2010)

cuznguido said:


> It is your money, but if I was going to go with a 383 i would scour the earth until i found a 400 block and do it right. You will be happier in the long run. Stroking the 350 block to get those cubes requires some pretty serious compromises that end up costing big $$$$$$ sometimes.


Why would I want a 400 block to build a 383? I want a good torquey street motor 

If I had a 400 block I would just build a 406 or 412 (4.155" or 4.185" bore respectfully and 3.750" stroke crank). I wouldn't build a 377/383 by using a 400 block (4.155" (377) or 4.185" (383) bore) and a 350 crank (3.480" stroke). Those are high RPM motors, not high torque motors. I'm looking for a good street torque motor, not a high RPM screamer.

Building a 383 using a 350 block (4.030" bore) and a 400 crank (3.750" stroke) is probably the most popular stroker motors ever built. Building them the other way around using a 400 block and a 350 crank are geared more towards high RPM specialized race motors. 

My friend built a 377, 400 block, 350 crank (4.155" bore and a 3.48" stroker) a few years ago for his 2nd Gen. Camaro. It totally sucked on the street, it needed to rev. It was ok at the track. He had to run 4.88 gears and a 8 inch 5000 plus RPM stall converter. He wasn't much quicker then my 406 at the track. My 406 ran like a kitten, on pump gas, Hooser Quick Time tires. 3800 stall convert, 4.10 gears. 

There is a little grinding to do on the 350 block to get the right clearance for the larger stroke crank. It's no big deal though. My rods are stroker rods so there shouldn't be much clearance work involved. All I need is .060" clearance between the block an crank/rod.


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## 2000ssm6 (Feb 10, 2010)

A 383 is the way to go for a budget build. Those put together right are torque monsters. You could always add a small shot of spray if you are not happy.


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## indiansprings (Feb 10, 2010)

In this part of the country it is getting harder and harder to find a GOOD original 400 small block, the dirt trackers have gathered them all up to make the 383's. 400 block 350 crank. I've got one that was all original out of a 72 Monte Carlo sitting out in the shop, ready for a project one of these days, along with a 402 BB, 350 4 bolt and another DZ 302 block. Just time and more money, something we seem to never have enough of.


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## NYH1 (Feb 10, 2010)

2000ssm6 said:


> A 383 is the way to go for a budget build. Those put together right are torque monsters. You could always add a small shot of spray if you are not happy.


Another reason why I went with forged pistons instead of hypereutectic pistons.


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## Den69RS96 (Feb 11, 2010)

I added your info to comp cams CamQuest software and with the vortec heads and the xe268 you should be making 375hp and 439 ft/lbs of torque. 

Since your building a 383 you might want to step up to a 195cc head and a 750 carb. I think the stock vortecs would hold your combo back. The vortec intake runners are 170cc which is kind of small for a 383. If you used a bigger, better flowing head with 195cc intake port like dart iron eagle, Dart pro 1, or a set of brodix IK200 and a 750 holley, you would well over the 400hp and 450 ft/lbs, but it would seem like a very mild street engine. All these heads are roughly around 1100 for the pair so it would add another $500 to your build, but in the end I think you would be much happier.

A while back superchevy tested a xe268 on a 350 crate engine with trickflow heads and made 416hp. The used an rpm manifold 1.6 rollers and a 750 holley carb. Since your starting out with a few extra cubic inches, you could have a nice 400-450hp daily driver with great street manners. 

Well whichever head/cam combo you choose, make sure you add a bottle of EOS or cam break in lube so you don't wipe your cam lobes out the moment you fire the engine.


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## RobertN (Feb 11, 2010)

Toss that GM block and put a real 383 in there 

Is there a benefit to a GM stroker 383 over just running a stock stroke 396?

For torque, did you see the magazine some months ago where the guy built a 10 second, 25mpg+ Duramax Chevelle? He had some big $$$ in to it though...

edit: funny I mention a real 383; did a little web search, and one of the first things that pop up is putting a 413 crank in a 383, to get a 432" motor



NYH1 said:


> Why would I want a 400 block to build a 383? I want a good torquey street motor


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## NYH1 (Feb 12, 2010)

RobertN said:


> Is there a benefit to a GM stroker 383 over just running a stock stroke 396?


For me yes. My 383 is being made out of a small block 350. 396's are big blocks. If I was going to put a big block in the car, it'd be bigger then a 396, at least a 454. Big blocks cost a lot more money then small blocks.


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## NYH1 (Feb 12, 2010)

Den69RS96, all I'm looking for is an honest 350 HP and 425 FT. LBS. of torque. I'm not going to be able to use the added power larger heads will make. The car is going to be a daily driver/mild street performance car. Stock type suspension, radial tires ect. I'm actually going to put larger front and rear anti-sway bars on it so it handles the corners better. That's going to kill my straight line acceleration, more power will only make it worse. I'll probably have more power then I need with the combo I'm building. If I do want a little more power, I'll put a 100 horse hitter on it.


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## NYH1 (Feb 12, 2010)

NYH1 said:


> For me yes. My 383 is being made out of a small block 350. 396's are big blocks. If I was going to put a big block in the car, it'd be bigger then a 396, at least a 454. Big blocks cost a lot more money then small blocks.


Plus I don't want the added weight of a big block.


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## RobertN (Feb 12, 2010)

Good point...



NYH1 said:


> Plus I don't want the added weight of a big block.


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## NYH1 (Mar 1, 2010)

I ended up going with a Lunati hydraulic flat tappet cam. I bought one of their Voodoo 262/268 cams. Spec's are 219/227 dur. @.050", .468/.489 lift, 112° LSA, 1400-5800 RPM range. That RPM range is based on a 350. The added displacement of my 385 will lower the operating range a few 100 RPM's. Lunati said it'll basically be off idle to 55/5600 RPM's. It should make really good low and mid range torque. That's right where I want it to be.

I went with the Lunati over the Comp Cams because I read and heard that Comp Cams Xtreme Energy series flat tappet cams make a lot of noise and they've been having higher then usual warranty issues with them. 

I always used to use Crane Cams and had really good luck with them. They went out of business a while ago and are just getting started again. They told me they weren't going to start making flat tappet cams until late March at the earliest . Between them just getting started again and not making what I want for another 3 to 4 weeks I figured I'd give Lunati a try. I've always heard good things about them.

Now I have to get my rotating assemble balanced, put my cam bearings back in and file fit my rings and my short block will be ready to be assembled. I bought the proper tool for installing and removing cam bearings in SBC engines. I took the cam bearings out so I could make sure there was nothing behind them from when I ground the clearances into the block for the longer stroke crank. I could completely rotate my assemble without it contacting the block anywhere. However there were a few places that needed to be ground a little so I had the proper .060" clearance I needed. 

I also had more then enough clearance between my rods and the cam lobes so I didn't have to grind any off the rods which was good. The Scat kit seems like a really nice kit. The finish machine work was right on. My machinist recommended I use Scat products instead of the Eagle products I was going to use. I'm glad I listened to him!


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## ratman36 (Jul 30, 2015)

NYH1 nice build. I built race engines and street engines you have good general knowledge. The other folks are here making comments should stick to chainsaws because they definitely are not knowledgeable about sbc engines.


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## NYH1 (Jul 31, 2015)

My progress has been a lot slower then I would have liked with this car. I guess that's the price we pay when we have other hobby's we're into like guns, hunting, ATV's.....and have a bad back! Once I get the body and interior done I might get a ProCharger for it. I'm not going to run a lot of boost but enough to give it a nice kick in the pants!

NYH1.


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