if i wanna run 12-15 psi intercooled
whats a good crank and rods to buy that dont break the bank?
im already buying forged pistons.

and whats the max compression i should run with the rods and crank you suggest.

thanks

 

Summit has forged cranks and rods (up to 650 HP) and pretty good prices on them, look on summit.com or order a catalog (free)

 

there are several guys on ebay each week selling H beams for around $300 and a stock 350 forged crank can be a serious piece.

 

i've already decided on a callies dragonslayer crank. i wanna find some rods that have a real good name and id rather buy them new from somewhere than off ebay. just because its such a big chunk of change.

 

Look into lunati for rods they make great stuff.

 

ive been directed to manley rods. any thoughts?

 

:: immature chuckle ::

 

thank you for me wasting my time to come read this. ***

 

I would look at the Lunati stuff as well, they make nice rods and cranks.

 

Just a joke. Geez. My bad.

 

B4Ctom1, have you bought this sort of thing from eBay before? Were you satisfied?

 

Building a bottom end is not jsut a selection of parts. It's also the assembly of those parts to correct tolerances and specs.

If you don't know how to do it and your shop is not expereinced in how to do this they will build you a very nice, expensive hand grenade. It will go "boom" soon after you start to have fun with it.

Here are jsut a few things that shops get wrong that typically build high revving N/A motors:

1. Too much bearing clearance. They like to open up the clearances and then put on a high volume oil pump and thick oil so you don't starve it at high RPMs. Good for N/A. Very very wrong for a blower. You want tighter tolerances (like stock) which can hold a much stronger film strength- which is what you want to support massive torque at moderate RPMs.

2. Piston-to-wall clearance too tight. More heat into the pistons under boost means more expansion of the piston. Tolerances on the looser side of the spectrum are what you want.

3. Piston ring gap too tight. Supercharged engines throw a LOT of heat into the top ring. This causes it to expand and can butt the ring ends together. When this hppens your engine is about one revolution away from catastrophic failure. The butted ring locks at TDC and when the crank tries to yank it back down big chunks of the piston above the top ring are violently ripped off like shards of glass. You can imagine what happens after that.

4. Too much compression. Lots could be said about this. Wrong choice of heads and pistons, etc, etc. If you think you're going to throw a blower on an 11:1 motor and run pump gas you're smoking crack.

5. Wrong cam. Cams that will let a N/A motor breathe well at high RPMs are all wrong for a blower motor that will see more moderate RPMs. Big durations and tight lobe sep angle will let a significant portiong of the boost blow right out the exhaust valve without ever contributing power to the combustion process.

Don't just shop for parts- shop for a place that really knows how to build a short block for a blower motor. Cheap parts assembled intelligently and with care will always outlast and outperform expensive parts that are poorly matched and poorly assembled.

 

ok thank you for wasting my time as well.
you did nothing but insult me with your post. its gonna be a 9:1 compression motor. and if i use peice of crap internals cast pistons etc its not gonna stand up. i simply wanted to know good qaulity peices to begin with.

 

This is how SinthetikIroc gets a useful response and trashes the poster for it....

I can understand you getting a little upset at me because of my off-topic post... but then someone posts a bunch of useful information and you say they're wasting your time... excuse Damon for trying to help...

Lighten up, good G<x>od...

 

he took it upon himself to make a post that makes me look stupid
i didnt ask what brand of lego wheels to use in my ****. i know all about checking clearances and what not. i didnt state "well i never touched an engine before but i wanna try" i know what im doing. all i asked was what brands of rods/cranks did people have and what they felt works best and what doesnt.

 

Well I understand what you're saying... I just figured his intent wasn't to offend but to help. But, eh. :: shrug ::

 

all im saying is if im gonna build a blown motor for 6-700hp im definitly not gonna use stock crank,rods,pistons and what not. im gonna do with something a lil higher up in the food chain.

and i would never spend 6-7 grand on a motor blindly.

 

must be that time of the month

 

could be

 

Good points.

 

i know alot of people come on the boards with high hopes for qaud turbo irocs and other silly ****. but too many people are quick to perceive everyone as somebody who has some crazy idea that they cant acheive. i didnt like his post kus even after all the **** he said. he still didnt reccomend any brands to check out.
but its already been decided on manley rods and callies dragonslayer crank and speed pro forged pistons.
thanks for all the help