[vinniekq2]

A low deck 350 wont take a 4 inch crank(that I am aware of) The 3.875 crank just barely fits(unless there is a new crank Im not aware of.So,401 from some GM 350 blocks is the max. The 4 inch crank goes into a 400 block to make a 434(thats what I have)

Ive been trying to price out a boosted engine myself. So far I dont see building an LS 5.3(cheapest core) that makes decent power for less than 12k
some members here can piece meal used turbos for a lot less.I dont see how
hope someone will step up with a full parts list???

[ChevroletSS]

The block was a good running motor and when I took it apart the main caps got misplaced somewhere. When I get the block back Im gonna take it somewhere else and have it done. Seems like this guy dont feel like messin with it. Not good for buisness

[ap72]

Originally Posted by vinniekq2

A low deck 350 wont take a 4 inch crank(that I am aware of) The 3.875 crank just barely fits(unless there is a new crank Im not aware of.So,401 from some GM 350 blocks is the max. The 4 inch crank goes into a 400 block to make a 434(thats what I have)

Ive been trying to price out a boosted engine myself. So far I dont see building an LS 5.3(cheapest core) that makes decent power for less than 12k
some members here can piece meal used turbos for a lot less.I dont see how
hope someone will step up with a full parts list???

Most guys running the 5.3L turbo motors don't have a lot of extra money to blow, so they just run stock long blocks with a cam, injectors, a single turbo off stock manifolds, and tuning. You're looking at some fabrication there and maybe 3k for the whole deal. It's definitely a DIY job though and if you start looking at buying parts from a catalog to build an engine you may as well start with an LSX or better block. Kinda like you did with your 434


As for 4" stroke in a 350 block- it can be done but requires extensive clearancing and possible welding after you grind into water jackets.

[cdminter59]

Originally Posted by ChevroletSS

I have a very good condition crank I'm taking to the machine shop to get checked. Does anyone make a kit with just rods and pistons??

Check with CNC Motorsports: 350 SB Chevy SRP 9.8:1 Pistons, Plasma-Moly Pistons Rings, Eagle 6.000 H-Beam Rods Combo - Piston Rod Combos | CNC Motorsports | Car Parts | Truck Parts | Competition Engines

[techinspector1]

I wanted to go back through this thread and make some observations and comments about questions that have been raised......

Originally Posted by ChevroletSS

What is the purpose of 6 inch rods compared to 5.7 inch?? Are 6inchers what are in 400sbc?? Im trying to figure out what rods Im gonna go with. Do you need shorter pistons with 6 inch rods???

There are a couple of advantages to using 6 inch rods versus 5.7 inch rods.
1. Less side-loading of the piston skirt against the cylinder wall would seem to me to lessen friction and allow more horsepressure at the flywheel.
2. A longer rod will require a shorter piston compression height, allowing more room for the counterweights of a stroker crank to clear the underside of the piston at bottom dead center. The more counterweight you can use, the less Mallory Metal you will have to use to balance the reciprocating assembly. (Mallory is expensive to buy and expensive to drill the counterweights and insert the heavy metal).

The main disadvantage to longer rods, in my opinion, has been the fact that the wrist pin gets pushed up into the oil ring space and you must use another rail to prevent snagging of the oil ring ends in the wrist pin hole. It just smacks of a band-aid fix to me and adds the complexity of more parts to go wrong in the long run.

Lately though, some piston manufacturers have stepped up to the plate with a concentrated ring stack that allows the wrist pin to be clear of the oil ring groove. I'm stoked over that and no longer have any issues with using a 6 inch rod in a SBC build. If I were to build a 383 tomorrow, I'd probably use forged Probes or other quality pistons that feature a concentrated ring pack along with a Scat cast steel crank and 6 inch Scat I-beam rod. David Vizard has taken 550+ hp out of the Scat cranks and rods for years now with not a single failure according to what he writes. Good enough for me.

400 small block Chevys came from the factory with a very short rod, 5.565 inch. I'm sure the GM engineers took side-loading into consideration when they designed the motor, but its intended use in station wagon and large family sedans (low rpm operation) made it worthwhile to use the shorter rods to clear the cam and oil pan rail.

Originally Posted by ChevroletSS

But what is the difference in the rods besides length???

6 inch rods will dwell the piston longer at the top of the stroke, while dwelling it for a shorter period of time at the bottom of the stroke. Some folks feel they can get an advantage of dwell time at the top of the stroke to allow the mixture to burn a little longer and make more cylinder pressure. Other folks will tell you that there is no free lunch and that if the piston dwells longer at the top of the stroke, then it must, of necessity, dwell for a shorter period of time at the bottom of the stroke, decreasing cylinder fill time before the intake valve closes.

As I stated above, the main advantage of a longer rod for me, at this point, is to make it easier and cheaper to internally balance the motor and to reduce side-scuffing of the piston skirt against the cylinder wall.

Originally Posted by ChevroletSS

I think Im gonna go with an assembly internally balanced with 5.7 rods. Its hard to pull the trigger and throw money at this cause I just wanna make sure I get what is best.

I would advise internally balanced with 6 inch rods. It'll be easier to balance.
Now, you may come back to me and say that the assembly you're purchasing is already balanced. BULLHOCKEY. Get all your parts together and take them to the machine shop to be balanced. TRUST NOBODY.

Originally Posted by ChevroletSS

Also what's the difference in 5140,4260,8740, and 4340 rods and can I go longer than 6 inch and I what about h beam, I beam, or a beam. Floating pin or pressed fit pin. Does it matter if its shot peened or polished and shot peened finished. Straight or tapered.....

Different alloys of steel are used by different manufacturers depending on load, cost, machinability, etc.

Properties of 5140 steel.....
eFunda: Properties of Alloy Steel AISI 5140

I don't think there is a 4260 alloy....

Properties of 8740 steel....
eFunda: Metal Alloys Keyword Search Results
http://www.suppliersonline.com/Resea...1&Mechanical=1

Properties of 4340 steel....
http://www.suppliersonline.com/propertypages/4340.asp
eFunda: Metal Alloys Keyword Search Results
4340 Alloy Steel Alternative | Pennsylvania Steel Corporation :: Flexor
Tool Steel, Alloy Steel, Powdered Metal - 4340 Alloy Steel

Longer than 6 inch? Yeah, there are SBC rods available up to 6.5 inches, but I suspect the custom pistons to use them would be very expensive. Personally, I don't know because I have never had the need for 6.5 rods because I have never built a 1,000 hp SBC.

I-beam rods will work fine in most any motor that any of us put together for street use or occasional drag strip blasts and generally are less expensive than H-beam rods, which will hold together better in high-hp applications.

Pressed pins are the norm for street/strip motors. Floating pins might be a better choice where the motor will be disassembled frequently, like in a circle track motor or Competition class drag racing motor. And, the lock rings used for floating pins adds complexity to the mix, something else to go wrong (like popping out of the pin bore or breaking and wrecking the piston and cylinder, for instance).

Shot peening will add roughly 100% strength to the resistance to cracking. Cracks generally form on the outer surface of a part rather than further inside the casting or forging. Peening closes the "skin" of the material and discourages the formation of cracks. Polishing is another way to help prevent the formation of cracks in the outer skin of parts. First you smooth and polish the part, then you shot peen the part.

Originally Posted by ChevroletSS

What's better, dished or flat top pistons.

It's not a case of one being better than the other, it's a case of using whichever design you need to bring your combination together. Personally, I think a guy would be better off centering his build around a flat-top piston just for the flame propogation and squish properties involved, but that's just a personal feeling. Adjust the chamber volume to arrive at the proper static compression that you're shooting for and the proper camshaft intake closing point to arrive at the dynamic compression ratio that you're shooting for. COMBINATION, COMBINATION, COMBINATION.

Originally Posted by ChevroletSS

If it has 50 less no biggie. Just knowing I got good parts capable of making those numbers are good for me. I dont even have a dyno anyway so it not like Ill actually know which sucks and I dont know anyone who has one

I like your attitude. I know that when I was playing with the DynoSim program, many times I spent several hours just changing cams and altering the installed positions of them to gain another 5 or 10 hp. For instance, it's pretty easy to pick up 10-15 hp with 1.6 rockers over the standard 1.5 rockers, particularly with good heads. Many times you can pick up another 10-15 hp by advancing or retarding the camshaft. Don't misunderstand, I would not automatically go with 1.6 rockers, but many times, if you have the correct camshaft timing in the first place, the extra valve lift will put you over the top. My very best advice to you would be to invest in a DynoSim program and play with it. 150 bucks will get you the latest software with an 8000 camshaft file to pick from. You'll be able to tweak components and see what will work best for you before shelling out the shekels. I have no doubt that with the software, you could mirror the results that were achieved by the folks who put the combination together and tuned it for AFR.
I very highly recommend the following 2 products.....
DynoSim5 Main Page
CamDisk8™ CamFile Library Main Page

Originally Posted by ChevroletSS

It doesnt make sense to me that you can bye brand new main caps for a block and get them line honed to work but you cant take used main caps and make them work.

Aftermarket caps have more meat on them, making it easier to make a round hole. OEM caps will take a lot of labor time to match up and maybe your machinist figures that you will not want to pay the labor time for him to do the matching up. You can cut into the main saddle only so far, even though there are short chains available for the timing set. As AP72 mentioned, if you're gonna pop for aftermarket caps, go with 4-bolt splayed caps.

[ChevroletSS]

Tech Inspector, you are the man, I wish I had you in my auto tech class back in high school. You should be a teacher. Anyway that software seems ok but I dont see how it could give real results. Has anyone tried it before?? My machinist told me that Id be better off getting a different block. He said 130 bucks to line bore it. I cant find a block for under 400 dollars. He also said that making it a 4 volt would make it weaker and that all the racing guys are using 2 bolt. Im serious when I said Im wanting to go somewhere else. They do good work there but seems like sometimes he dont want to do the work. I mean If I want to pay for something then do it. Unless its impossible. Oh well I gotta take my roller block in the basement up to him and get the other block back with no caps. He told me they throw the blocks away with no caps but u couldnt pay me to throw it away. Ill keep it and find someone to line bore it.

Thanks guys

[1Gary]

Car-Part.com--Used Auto Parts Market

That is listings for junk yards in your area,just plug in your zip code.96 to 2000 truck 350's is the engine of choice.There are tons of them out there for a good bare block.The old tech was OEM 4 bolt blocks had a cracking problem on the outside bolts,but that has been resolved yrs ago.


All the yrs we have run 9.90 in 2350lb car each being hit hard with a tranny brake,there hasn't been a overwhelming number of engines we used aftermarket main caps.Do you need splayed caps??. I don't think so.

[ap72]

Originally Posted by ChevroletSS

Tech Inspector, you are the man, I wish I had you in my auto tech class back in high school. You should be a teacher. Anyway that software seems ok but I dont see how it could give real results. Has anyone tried it before?? My machinist told me that Id be better off getting a different block. He said 130 bucks to line bore it. I cant find a block for under 400 dollars. He also said that making it a 4 volt would make it weaker and that all the racing guys are using 2 bolt. Im serious when I said Im wanting to go somewhere else. They do good work there but seems like sometimes he dont want to do the work. I mean If I want to pay for something then do it. Unless its impossible. Oh well I gotta take my roller block in the basement up to him and get the other block back with no caps. He told me they throw the blocks away with no caps but u couldnt pay me to throw it away. Ill keep it and find someone to line bore it.

Thanks guys

If you're using a stock block you may as well use stock caps, I have thrown away blocks because they didn't have caps in the past and I'd do it again. A stock block is only good to around 500hp, and at that level stock caps will work fine. If you need to keep the block you can upgrade the caps, but then something else will break.

Your best bet is to find a good running 350 that has been well maintained and has very minimal bore wear. Then all you need is a honing, maybe freshen the decks and you're good to go. While you're looking for engines keep an eye open for Vortec engines, LT1's, and maybe a 5.3L LS engine. They'll all pop up for less than $500 occasionally and make a GREAT start for a hot street build.

[ChevroletSS]

Well I have a 94 350 roller I am going to take up the machine shop so he can get started on that. Cylinder walls look awsome. The hole block does. But thanks for the link, thats wasome , I never knew there was a site like that. What vehicles had a 400 sbc so I can try and find one and a chevy big block

[hcompton]

Originally Posted by ChevroletSS

Well I have a 94 350 roller I am going to take up the machine shop so he can get started on that. Cylinder walls look awsome. The hole block does. But thanks for the link, thats wasome , I never knew there was a site like that. What vehicles had a 400 sbc so I can try and find one and a chevy big block

94 engine should be good roller block. The other block without caps may not have any value. Two bolt caps are fine. Do use two bolt blocks that are cross bolted not just the stock two bolts. But i have never stretched a cap bolt. Other engines will pull the bolts out and trash the crank but for chevy small blocks its pretty damn hard to trash one with just well tuned hp.

70s impalas came with 454s as an option. Also most trucks. 400 engine is no big deal. I would not spend time hunting one. A New block is not as crazy priced as you may think. Same goes for the big block. Once it needs line bored on the crank and cam well you covered at least half the cost of a good after market block from world of products or dart.

[ChevroletSS]

I dont know where you get your blocks but any aftermarket block to me is outrageous. Summit sells a gen1 4 bolt for I think 6 or 700 and thats kinda high for me. I would buy one from summit if I had the money cause they make them extra thick but dam only way I would buy an after market block is if I was rich or building an all out race motor. I always wanted a 396 big block and never could find one or any big block for that matter.

[ap72]

Originally Posted by ChevroletSS

I dont know where you get your blocks but any aftermarket block to me is outrageous. Summit sells a gen1 4 bolt for I think 6 or 700 and thats kinda high for me. I would buy one from summit if I had the money cause they make them extra thick but dam only way I would buy an after market block is if I was rich or building an all out race motor. I always wanted a 396 big block and never could find one or any big block for that matter.

Summit blocks are just reclaimed OEM blocks, there's not a damn thing special about them.

[hcompton]

Originally Posted by vinniekq2

A low deck 350 wont take a 4 inch crank(that I am aware of) The 3.875 crank just barely fits(unless there is a new crank Im not aware of.So,401 from some GM 350 blocks is the max. The 4 inch crank goes into a 400 block to make a 434(thats what I have)

Ive been trying to price out a boosted engine myself. So far I dont see building an LS 5.3(cheapest core) that makes decent power for less than 12k
some members here can piece meal used turbos for a lot less.I dont see how
hope someone will step up with a full parts list???

Vinnie this is off topic but the cheapest turbos are not used. Actually the junk yard usally wants a few bucks for them. But a remanufactured turbo from garrett is not that much and they come guaranteed. My t3/t4 supports 600 hp and cost 384 bucks from garrett. I would use two on a v8. Oversized turbos help make bigger power with lower charge temps.

You can usally put an fmu on the turbo that is mechanical for under 100 bucks. Needs a return style fuel system. For big power you will need to reprogram the computer to take boost. The gm sensor package already reads boost so its really just some slick programming. Or at least the new map sensor. So that just leaves manifolds which are usally factory with the ends/cats cut off and piping welded up or a turbo flange welded right onto the end of the manifolds. Charge pipe should be aluminum and exhuast all mild steel you may need to beat it around and do some difficult welding so mild steel pipe is best. You can buy the flanges off ebay or jegs for under 20 bucks. Silicon couplers and clamps can also be purchased with a nice lot of charge pipe off ebay. Intercoolers are cheap dont buy an expensive one. Turbo powerstroke intercooler is a personal favorite and lots of ppl use them so they are easy to find.

http://www.ebay.com/itm/T04E-15PC-T3...3c1d67&vxp=mtr

[ap72]

aluminum pipe SHOULD be used, but many people use regular old exhaust pipe. Why? Because its cheap, easy, and can be bent by any local muffler shop. It can also be easily welded to for things like BOV's or extra injectors.

And for peak power larger turbo's definitely help, but for off idle power that little t3/t4 will pull like a diesel. Something to consider on the street.

ON A STREET CAR smaller turbos definitely have some advantages.

[ChevroletSS]

Ok guys Im buying my rotating assembly today but first Im having trouble on what cc piston to get. I want my compression to be between 10 and 11 to 1 so I can stay with pump gas or maybe a half mix with racing fuel. But anyway Ive been looking at some kits and some show you what your compression would be with whatever cc piston they are offering. Does anyone know what the CR would be with +12 cc dished piston, or a +5 cc dished piston. Reminder this is for a 383.