does this make sense?

i looked at a rebuilt 429 motor today from a 3 ton truck, it is a d9 block with a steel crank and c9 rods. Does this make sense of did someone assemble a pile of parts from different motors?

cooter wrote:i looked at a rebuilt 429 motor today from a 3 ton truck, it is a d9 block with a steel crank and c9 rods. Does this make sense of did someone assemble a pile of parts from different motors?

Based on your limited description, it makes perfect sense. The C9 is the rod cap forging, not the connecting rod forging. By the way, the 429 commercial engine rods are shorter than the 429/460 passnger car & light truck rods.

Paul

Paul, for reference may I ask how much shorter these rods were?

so would this make a good base for a 350hp street motor if i used a better set of heads? It is a stock rebuild. Where the steel cranks good for auto applications or is there something different about them?

bb429power wrote:Paul, for reference may I ask how much shorter these rods were?

That's not a dimension I keep in my head, but I'm sure you could find it on the internet if you really need to know. The OEM piston in the 429 passenger car engine has a 1.89" compression height, while the OEM piston in the 429 commercial truck engine has a 2.09" compression height; do the math in order to ballpark the rod length...perhaps around 6.405" +/- but I don't know the actual answer. I've had a few sets pass through my hands and they are shaped like the later model 460 double-dimple rods, only shorter.

Paul

cooter wrote:so would this make a good base for a 350hp street motor if i used a better set of heads? It is a stock rebuild. Where the steel cranks good for auto applications or is there something different about them?

Using that 85 pound crankshaft with those 1000+ gram pistons would be the very last way I'd build a 350 hp 429 (actually, I wouldn't build it like that no matter what). Besides, the crankshaft will not accept the passenger car accessories, not with its 1.75" diameter snout. And the rear flange has a rollerized pilot (or adaptor for an Allison) and neither will work with your passenger car AT or manual trans unless you do some machining back there, too.

For a 350 hp 429, I'd use a 460 crankshaft with some ported D3VE heads over flat tops and OEM SCJ-style camshaft (etc)....

Paul

thanx for the info, i thought for 100.00 the motor may be a useable piece but i guess it will just go to the scrap heap

cooter wrote:thanx for the info, i thought for 100.00 the motor may be a useable piece but i guess it will just go to the scrap heap

If I had the opportunity I would purchase twenty five of those engines for $100 each. The D9TE block alone is worth that much (we charge $175 for a D9TE core); the crankshaft still has a market -- an ever-shrinking one but it has market nonetheless if you don't mind all the machining ($350-$400 typical crankshaft value); the full-length pan has value too...among other things parts depending who you are and what you need.

But for a 350 hp engine, it's just the wrong way to go and you'll spend more than you have to, that's all.

Paul

in edmonton just grinding the crank costs more than 300 so if more machining was required the price would be 600!