Thread: 434 SBC info needed

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I've decided to build a 434 small block for our 87 Z24 Cavalier 1/4 mile drag car. I plan on using a World Product Motown block, 4340 4" crank, JE Pistons, 6" H beam rods, and also installing splayed caps. I'm shooting for at least 600+ hp and high 500 tq to be running on alcohol.

My questions are 1. What head should I be looking for? I'm thinking something like 227cc. Interested in AFR's but not sure if anyone has found that dart or any others performed better out of the box. Would 65cc combustion chambers be better for this? 2.Given the combustion chamber what would be the best compression ratio to achieve? I'm thinking somewhere around 14.5-1. But still not real certain. 3.Any idea what the starting point I should aim for with a cam? It's gonna be a COMP mech. roller and I'm looking for somewhere around 6500-7k shift point.

I know these are a lot of in depth questions but I wanted to get some opinions before I decided on my own. It seems techinspector is the man here so i'm sure i'll get some very useful info from you guys!

First, I would recommend using a Dart block rather than a WP Motown block because Dart has had a lot less issues with qualitly control. Secondly, I would call CompCams, Isky, Crane and Crower and see what mechanical roller cams they recommend for your application. Then go with the specs that are the "average" of all four recommendations. After that, call AFR and talk with their tech people. Their CNC 227 heads would be a good choice IMO, but I would get their input as well regarding chamber size and the possibility of some personalizing for your heads. American Speed in Moline, Illinois builds a 434 small block putting out 600 hp, and they use AFR 227 heads in their build. Let us know what you come up with.

http://www.stlracing.com/forums/showthread.php?t=122083

Might check with this guy for some very nice heads, He spent a couple years and Mega bucks building a UMP modified took it out the first night and got to run a few laps,spun a bearing and popped a rod. He decided that was the end of his racing career.Plus he got laid off last month so he might be willing to deal. Might be worth checking into. He lives in St.Peters,Mo.

I'm going to be dealing with a company called Ohio Crankshaft. They are a few hours south of me. The block comes part of a short block assembly I will be getting from them. I bought a rotating stroker assembly from them a few years ago and was very pleased. Don't get me wrong I do believe the dart seems to be superior according to what i've heard time and time again but I am confident that they will take good care of me. Not saying I won't decide on the dart but as for now thats what i'm leaning towards.
I ask these questions on here because everyone here are the customers of all these companies and have more feedback towards these companies. Any company i call asking for recommendations are more then likely going to stick with their product being that its their job to.
I was thinking about the 210 cc heads at first thought but more i thought about it the more I started to lean towards the 227's being this will need to breathe like big block.

I wish you luck with the world and ohio junk. I went through 3 cranks trying to get a good 3.875 stroker crank from ohio. Finally just sent the 3rd one back and charged back my credit card. Got a Callies Compstar crank instead--- perfect out the box. Scat is also a decent crank for the price. As for the world block, it has serious quality problems. Do yourself a favor and google them. I'm not the only one that had problems with either of them.

As for the rest... 210cc heads will not come close to feeding a 434cid at 7K rpm. You need something in the 227cc range minimum. By the time you finish buying shaft rockers and such for the AFR 227's, you could get the Brodix Track 1 233cc heads ready to go, and IMO, a much better head for your 434cid. http://awesomeengines.biz/small-bloc...233-cnc-heads/ You might also want to consider the Brodix STD 18 degree head. It pretty easy to use since it uses all stock sbc hardware/rockers.

The Brodix heads come with 68cc chambers. You would need an 8cc dome (JE 182031), 0-deck height, .040" gasket, to get 13.9:1 compression.

I would do a custom cam. Comp doesn't have a part number cam that I like for this combo.

I haven't come across a whole lot of bad things with the world blocks on the net? Where have you gotten all the info at about them? What's the major problems with them?

Also, what problems were you having with the crank from ohio crank? I've heard nothing but good about them in the past? A repeat NHRA and IHRA champ has told me that they are a very reputable company and that is why I went with them in the past.

I'm not tryin to be a hassle but I know that there are some people that just prefer certain companies.

Also i'm looking for 14.5-1 or so CR. Figured i'd be alright as long as piston/valve clearance is good and running alcohol

Looked at the site....Doesn't say much about their cranks, what materials, where they're made, fillet radius, tolerances.... Not saying they're bad, but I've run a few Callies and a few Crower Cranks, gonna take one heck of a good product to beat them!!!!!

I always get the cam last, and not until I have everything else done, ready, mocked up, clearanced, checked, measured, and rechecked on the rotating assembly and the REAL flow numbers on the heads, not the claims in the ad for the heads..... Tried a bunch of brands of heads, for out of the box quality, AFR is really tough to beat....but even the AFR's can be improved by a good head shop with a 5 axis CNC and a flow bench.

Sounds like you're building for performance and racing, don't think I'd be cutting corners on any of the components.

Never have seen a block, be it Dart, Donovan, WP, or an Aries that is ready to go out of the box.... They all need to be squared and decked for the rotating assembly you are installing. Think I'd be asking Pat McCarthey or one of the engine builders about what they have seen in their shop for quality, and not pay a whole lot of attention to a bunch of internet hype. I trust my machinist a whole lot more then some guy who might be nothing more then a poser or a wanna-be hiding behind a pretend name on the net....

Fever gave you some very good information that comes from a lot of experience building sbc's and not just reading about them. IMO his would be advice worth listening to....

I completely agree with the posers on these forums. In time I can usually filter through the ones that aren't taking me in the right direction. In the past 4 to 5 years i've spent my time and money building a 408w for my 80 Mercury Capri. For my info for this I found a guy who's been racing and running his drag racing business for over 40 years. He's been very helpful to so many people so I have complete confidence that he won't steer me wrong. Only thing is he is a huge ford guy so i'm not sure how partial he'll be towards chevys. So i'm not going to bother him with this build.

That is why I ask so many questions to so many people on this topic. I don't have the money or the time to be trying multiple manufacturers of heads, blocks, etc. So I look for a tried and trued combination to get me where I want to go. I don't build a bunch of performance engines so i'm not going to invest in testing equipment for flow and wet flow tests for a multitude of brands. I am also no machinst so I won't be doing all kinds of machine work trying different combinations.

I just want a healthy reliable 434 sbc with 600hp at least for a price tag of around 7-8k top to bottom. I wouldn't think that would be too far out of question here..

Originally Posted by chadrock

I haven't come across a whole lot of bad things with the world blocks on the net? Where have you gotten all the info at about them? What's the major problems with them?

Also, what problems were you having with the crank from ohio crank? I've heard nothing but good about them in the past? A repeat NHRA and IHRA champ has told me that they are a very reputable company and that is why I went with them in the past.

I'm not tryin to be a hassle but I know that there are some people that just prefer certain companies.

i had a customer that only used ohio crank short blocks i did rebuild them and did just short block on his race engines with new ohio cranks i had some in the shop not alot 15 of them there are ok there not a crower or a callies magnum the last ohio i had had a bad crank finsh on the journals very wavy but did get used .i would of sent it back but customer wanted to race .i have seen stuff from scat to that had bad journals that look like the ground the journals with a loaded wheel and grove the journals and have sent them back. to all this stuff comes from the same place i have seen them just about all makes.i have had cats scats and ohios setting in the shop at the same time they are all the same forging. i have guys running fast with cats scat ohios elgin and many that just came in a no name box s they all did work or made them work . if you have the time and no money the cheaper cranks are ok they work but if you have money buy a crower or callies

[QUOTE=chadrock;341637]

That is why I ask so many questions to so many people on this topic. I don't have the money or the time to be trying multiple manufacturers of heads, blocks, etc. So I look for a tried and trued combination to get me where I want to go. I don't build a bunch of performance engines so i'm not going to invest in testing equipment for flow and wet flow tests for a multitude of brands. I am also no machinst so I won't be doing all kinds of machine work trying different combinations.

QUOTE]


That's exactly why you need to be going through a reliable shop that does this kind of work all the time..... None of these parts are perfect as they come out of the box.....

I've had personal experience with Ohio also. I built a 434 a couple years ago. It took around a month and a half to get the rotating assembly. When I called I kept getting different answers as to why it wasn't shipped. (had told me 2 weeks and I called after 3). When it arrived one of the balancing holes in the counter weight was drilled off center and actually only had 3 sides from where it was drilled off the side of the counter weight.

I called them about this and was told they had gotten it off center but it "should" still be balanced and wouldn't replace it. On the same rotating assembly I had ordered it and asked if they would clearence a 2.08" intake valve, they said they would and it would be shipped within two weeks. When it arrived it was still only a 1.94" valve clearence.

It may have been a one time deal but I won't be doing anymore business with them.

Joe.

Originally Posted by chadrock

I haven't come across a whole lot of bad things with the world blocks on the net? Where have you gotten all the info at about them? What's the major problems with them?

Also, what problems were you having with the crank from ohio crank? I've heard nothing but good about them in the past? A repeat NHRA and IHRA champ has told me that they are a very reputable company and that is why I went with them in the past.

I'm not tryin to be a hassle but I know that there are some people that just prefer certain companies.

My info on them is from personal experience. The cam tunnel was so out of whack on the World block that I couldn't slide the cam in. I would have had to bore the cam tunnel for big block bearings. I was too aggravated at that point to do it so I sent the block back even though shipping came out of my pocket and cost more than the machine work.

The Ohio cranks --- (1) It needed to be turned 10/10 to clean up the journals. Sent it back (2) Snout was bent. Sent it back (3) Needed two slugs of mallory metal for internal balancing. Sent it back.

A Scat crank that was there for someone else would have needed some metal removed in order to balance out. My machinest turns the counter weights down in a lathe for balancing and that, IMO, is much better than adding expensive mallory metal.

Everyone is right that the off brand cranks are likely poured in the same China foundry. But, I think it makes a big difference on who finishes the crank. The Callies Compstar crank that I went with is an import that cost pretty close to the same as any of the other Scat, Eagle, Ohio, etc. imported cranks but the finish machine work is awesome and way better than the rest. Callies assured me it would handle 1200 hp.

Dave is right about all blocks needing finished machine work. CNC Blocks N/E does some of the best finish work on Dart blocks at an unbeatable price. Carl checks everything. Here is some of pics his work http://www.chevelles.com/forums/showthread.php?t=93124

Hope you make some good decisions and everything goes well.

Thanks for the info on Carl's shop... Took a look there and saw his spec sheet on block prep, looks like a good way to go whether it's an OEM block or an aftermarket block used for competition. Last block I got came from Comp Products, all it took was a phone call to get everything done right. Sure, it costs more, but quality work always does!!!!!!

I keep looking at the new Dart blocks, and when I do get one it will be bought from a shop with all the necessary machine work done and checks made. No reason to stick a bunch of money in parts for a block that may or may not be machined properly, parts are just too danged expensive these days not to have the extra work done on the block.... Just a matter of protecting my investment and making sure the engine is going to perform the way it should, and last for awhile, too......

Only thing I've seen lately that is correct "out of the box" is my Corn Flakes in the morning!!!!!!

putting the counter weigth in the rigth spot help with heavy metal .BUT if you have a heavy mass your going to add metal as well if a lite mass your cutting or drilling holes or cut counter weigth i have been there and done it .i keep heavy metal at the shop it some thing that happens i just did a 383 with a scat crank and one 1 inch slug in the front no big deal for me plug it and keep moving less then a hour of time and less then 40.00 for the heavy metal . cutting counter weight s is work to . i really do not care for pluging or drilling the hell out of them it all eats up alot of time but needs to be done stock stuff is not bad but when you use H beams or I beam rods flat top dome or dish pistons you can throw getting it done fast out the window drilling pins help as well as getting the right bob weigth the crank can suport a cheap crank as well as the big dollar cranks some times need cutting or pluging the cheap cranks are trying to cover every thing for every one that just can not happen .i have had usa made cranks that needed metal on my big crank who knows how much it will need or not? they did not know when they made it they would have to spin it with a ruff bob weigth they did not do it