Falicon, thats all that needs to be said.[img]i/expressions/face-icon-small-smile.gif[/img]

 

Like I said before, if you all want to replace your Rod, by all means - replace it. But in my opinion (and the last time I checked this was a forum of opinions) you dont need that with a 440 big bore kit.

I base that on talking with several race mechanics a year ago before my build, and my own experience of 4 years of engine building. The fact is, there are no signs of any problems with my rod after 1 year of racing.

This is one of those things that the builders love to sell you like stronger head bolts for the 440 kit. Again, its not needed. You can get them if you want, but after a dozen 440 builds that I know of, you dont need them. If it makes you more comfortable then get them. If you want to buy a new rod, then get one! All I am saying is that they are not needed in my humble opinion.

The sky is not falling - I dont have a bible to sell, and confessions are free of charge.

(PS - If your bore is not perfectly center, you will have rod problems)

 

cam is 234/234 Duration @.050 .488 lift. 3000 - 6200rpm TCI 3000stall.
Honestly, It's a waste, all it does is burn the tires. I am looking for a 67 camaro project.
I also have a Chevy C1500 454SS with som mild mods.

My lawnmower is even modded.( just a custom exhaust)

 

Anybody else put a race head in the EX?

 

i have one on with stock sized valves and i honestly didn't notice a large gain. however, i only run a 11:1 426.

 

Cals400ex,

I wouldn't consider a ported head a race head. A race head should at least have performance cams, valve springs, porting, and larger valves. If you don’t have larger valves, head porting alone probably won’t make a large gain. I would consider a race head the final step in a combination of mods like a high compression piston, shortened valve guides, hard weld rockers & performance carb. All of those components beg for more flow or are required to make the high flow components work. I ported head will help, but your congestion point will be the stock valves. A high flow exhaust, like an LTE, will finish off the flow problems.

marky

 

I thru a rod in my ex last summer. I put a carillo rod in my new motor, I have heard they are the best.

 

That sucks - Who did your bore job?

 

i tend to disagree. most of the engine builders that i have talked to recommended drop in cams, stock valve springs, and stock sized valves. they said if you did anything to the valves only go up 1mm and just on the intake side. by the way, this was for 416's to 440's. they mentioned the +1mm on intake can help on high compression bikes with bores larger than 440, but it would still be minimal. even with the larger valves, a ex head can only flow so well. not one of the best designs in my mind. i haven't talked to an engine builder that recommended hardened rockers and a hardened cam. sparks did mention it, but by no means talked it up. the others didn't even mention it. they also said only run stiff valve springs with hardened cams. none of the drop ins need stiff springs, according to them.

 

cals400ex,

The race head helped me with 1mm over on both exhaust and intake. I beat a similarly built 440 without a race head up comp hill by three lengths - and I had weigh 70lbs MORE than him. Of course, I am running a 13:1 piston. Im surprised that your mechanics did not mention the other components. I have found that the big builders dont give up all thier secrets, but would rather promote thier name, rather than the components they use - that way they can charge more. Check out what the parts manufacturers recommendations are, rather than just the builder. Every part has a slightly different recommendation. For example, here are what Web recommends for my cams ....

"Web 479 Grind Cams: Performance profile increases overall power. Designed for use with a racing piston and exhaust. Must use spring kit with shortened valve guides. Compression release removed. Hardwelded rockers highly recommended!"

Find all the 400EX Specs for Web Here: http://www.webcamshafts.com/

So for me, I followed them to the T - Simply because they are the guys that design these items - they know what will work and wont work with each component because they actually designed them.

If they are not recommending stiff springs, then the cam they are choosing is pretty mild. The taller the lift and longer the duration, the more important the stiffer springs are - it just depends on the cam. If you get a cam that requires a stiffer spring, and dont install the stiffer spring, you run the risk of the valve floating (not closing all the way). When this happens, you then will lose power, and run the risk of a colision between the valves and the piston because the valves cant get out of the way of the piston in time. This is much more of a problem when at high revs with a high compression piston. A high compression piston has more mass on the top of the piston, and the clearances are a lot less. Add a lightened flywheel into the mix (which makes your motor rev quicker) and you are just asking for trouble.