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383 kit

bad link, to link off the new summit, right click on the product area with the item open, and copy & paste that link. The link you gave was just your searching one.
 
adamforsythe said:
Hello,
I am thinking about turning my 350 into a 383 stroker. Is this a good 383 kit?
http://store.summitracing.com/partd...ESP-B13004E030&autoview=sku&Ntk=KeywordSearch
Thanks
Adam
Click to expand...

The components of that kit look pretty good. What heads are you going to use? The pistons in that kit have an 18cc dish. You would need close to a 64cc chamber in the heads to get a decent compressoin ratio.

In my 388, I have a 12cc dish with 72cc chambers and my compresson ratio is 9.46:1. Just something to think about...... ;)
 
Hello,
I am going to be running these heads: http://store.summitracing.com/partdetail.asp?part=WRL-011150-1&FROM=MG
With this cam
http://store.summitracing.com/partdetail.asp?part=CCA-12-239-3&FROM=MG
Thanks
Adam

Beast388 said:
The components of that kit look pretty good. What heads are you going to use? The pistons in that kit have an 18cc dish. You would need close to a 64cc chamber in the heads to get a decent compressoin ratio.

In my 388, I have a 12cc dish with 72cc chambers and my compresson ratio is 9.46:1. Just something to think about...... ;)
Click to expand...
 
That looks exactly like the engine I was going to build for my old '79, and it's pretty much the same engine I have in my 81, (only the PO put a much bigger cam in there, and I may tone it down some in the future) and let me tell you, that bitch is a MONSTER :D

Just make sure you have the rotating assembly balanced.
 
that cam is pretty small for a 383 with Sportsman IIs on it. a set of S/R Torquers would be better matched to your application. keep your compression ratio at around 9:1-9.25:1, and you'll still be pump gas friendly with that cam and 64cc heads.
 
The cam is way too small for that combination, i would avoid the 4x4 series that comp makes cause the lobe separation angle (111 degrees) is a little wide for that recipe, 109-110 should be the goal for a 383.
i run a XE274H in my 357 cid rat killer.
i would use the XE268H as the starting point for that motor, 200 cc intake runners are gonna hurt the bottom end in a big way but mid-range and top-end will kick butt.
i would also choose the straight plug versions and keep in mind that 383's don't like to rev over 5500 rpm.
383's will make 35 more ft lbs of torque than a similar 350 and make it lower in the powerband.
You do know that block machining is required with the stroker kit....don't you?
 
Hello,
Lets say I did not stroke it but still went with the heads and cam how much less power would I have then a 383 with the same combo?
 
Adam the 200cc intake are geared towards a pro-street motor, you're gonna hate em, trust me.
180's are ideal for anything but the most radical street engines and the Dart's have a better exhaust port than the World's,
AFR's are the cats meow but their aluminum and cost a bit more.
The cam you've selected was my first cam when i built this motor the first time, i was not impressed with the bottom end but it had great mid-range.
If ya run about 10:1 compression the small 4x4 cam will make almost 390 hp
and just a touch over 400 lbs ft of torque....these are educated guesses and can't be verified so take it with a grain of salt.
The SBC happily enjoys 230 degrees of duration at .050" lift with a hydraulic cam and 240 degrees with a solid lifter design, both cams are totally streetable and will rock the house in the soft stuff.
350 cid engines need about 270 degrees duration (advertised) to make max torque and the XE268 hydraulic flat tappet falls right in there.
Too little duration equals high cylinder pressures at low rpm whereas too much duration equals low cylinder pressures at low rpm so it's balance thing man....you want high velocities at low rpm (180cc intake runners), fairly stout static compression ratios (9.5:1-9.75:1), compact combustion chambers with great exhaust ports (Dart Iron Eagle or AFR 64cc), and a cam that works with the motor (weve already been there).
Good luck bro.....lemme know if i can help ya more !
 
What I am after is something that will give me a low and midrange and I want the rough idle sound. To tell you the truth I am really after the sound. I don't need a really rough idle just something that will make the engine sound good. I don't want a soft smooth idle like a stock 350 has.
Thanks
Adam


Mad-Dog said:
Adam the 200cc intake are geared towards a pro-street motor, you're gonna hate em, trust me.
180's are ideal for anything but the most radical street engines and the Dart's have a better exhaust port than the World's,
AFR's are the cats meow but their aluminum and cost a bit more.
The cam you've selected was my first cam when i built this motor the first time, i was not impressed with the bottom end but it had great mid-range.
If ya run about 10:1 compression the small 4x4 cam will make almost 390 hp
and just a touch over 400 lbs ft of torque....these are educated guesses and can't be verified so take it with a grain of salt.
The SBC happily enjoys 230 degrees of duration at .050" lift with a hydraulic cam and 240 degrees with a solid lifter design, both cams are totally streetable and will rock the house in the soft stuff.
350 cid engines need about 270 degrees duration (advertised) to make max torque and the XE268 hydraulic flat tappet falls right in there.
Too little duration equals high cylinder pressures at low rpm whereas too much duration equals low cylinder pressures at low rpm so it's balance thing man....you want high velocities at low rpm (180cc intake runners), fairly stout static compression ratios (9.5:1-9.75:1), compact combustion chambers with great exhaust ports (Dart Iron Eagle or AFR 64cc), and a cam that works with the motor (weve already been there).
Good luck bro.....lemme know if i can help ya more !
Click to expand...
 
Adam take a look at the comp High Energy 268H and the Magnum 270, these are both single-pattern cams and will give you the (sound) you're after with a healthy bottom end.
The XE cams are dual-pattern cams and work well with exhaust port challenged heads (factory stock) when trying to make big power up top.
The single-pattern cams will work better down low and in the middle but top-end will suffer cause the exhaust port can't keep up, that's why the XE lineup has more duration on the exhaust side to help clean out the spent gases at higher rpm's.
so a good set of heads prefer single-pattern cams and poor heads prefer dual pattern cams, but since you're not going to rev the engine very high then go with a tried and true single-pattern design and be done with it.
 
Adam, I'd agree with staying away from the angle plug heads. It's a pain finding headers for our trucks that will clear the plugs. I'm running the short plugs with a set of Thorley headers that are "made" for angle plug heads and they barely clear. It really limits your plug selection...
 
Adam,
I went with the Edelbrock aluminum angle plugs heads because I got a great deal from a friend. If I had it to do over again I'd run a set of World Products iron heads with 72cc chambers and straight plugs. I may still go this route in the future but I have too many projects sucking the wallet dry right now.

As far as the cam goes, I'm running the Comp CS X4 270H-11. I'd say this cam is way too big for crawling or even general four wheeling. I have it in my 56 4x4 that hasn't really seen any real off-road work but it works fine for me at this time. Listen to these guys when they advise you to go for the milder grind. You mentioned that you were looking for "the sound" and this cam has it but I think you can get the sound and the driveability with the 268 cam.
 
I've heard that the Vortech heads give you a real good bang for the buck. I've never used a set myself but I remember this coming up a long time ago on this site. You might try a search or someone else might chime in with some info. If someone has access to one of the computerized dyno simulators they might be able to run the numbers for you.
 
Hello,
The only thing that I don't like about vortech is that the intake valve is not 2.02. But I'm not going to be pushing 500HP so I think a 1.95 intake should do just fine.
Thanks
Adam
 
The GM vortecs have a bad habit of cracking and it's not repairable, if you in sist on Vortecs then buy the ones that World makes, their much better.
the Double-hump heads that Summit recreated are nostalgic but only have 165cc intake runners (great for a stock engine) and a restrictive exhaust port......... get a set of Dart 180's bro and quit fiddling...... lol

http://www.dartheads.com/chevysh.aspx
 
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