602 GM Crate vs. Built Engine

[Brian W]

The lightest rotating assembly I can put in and appear to be legal will cost you somewhere around $4000. And that is just the crank, rods, pistons, and rings... And no, I have not sold alot of them because most racers running this class don't have that kind of cash.

[IMCADW]

Well, if one went thru tech at Boone, and it was a fast then it would have been Brian. He was right ahead of a claim motor with about $2200 in it at the end of the feature.

[Brian W]

the 500 cfm stock cars have the same shortblock rules.... as do the sportmods... and one of them had one of the "good" cranks.

[IMCADW]

That crank win the race then? I don't think you get the point. In 2009 at Boone, a 355 with 305 Heads, Stock crank and rods, hyperutectic pistsons etc qualified and ran top 10 in the A Main in stock cars. That was with a 350 Carb...

[dirtracr5]

Imcadw...it appears you are the one who doesn't get the point. You first claimed that a motor couldn't be built and be legal at that cost. It clearly can be and be legal. Now your changing your argument to whether or not cranks win races??? Wtf?

[IMCADW]

I can build you a 50,000$ engine too, but would you buy it? Real the IMCA Rules, Lightweight cranks are not legal. It's like a gas ported piston, you get away with it UNTIL you get tore apart. If you want to spend that kind of money, go ahead. You're not getting the point.

[IMCADW]

You should know who I am Luke...

[dirtracr5]

You should know who I am Luke...

I should but I don't. What's your name?

[IMCADW]

Someone who knows better.

[dirtracr5]

You can pm me your name if your worried about your name being in public.

[IMCADW]

You'll soon figure out I don't care who knows who I am... Just making a statement that if you want to spend a ton of money on an engine that's not going to net you much gain that is your call. Remember, if they ever rip an engine apart, and weigh the crank your $1000 crank is out. It's not crankshaft, it's not connecting rod, nor piston with the rules. It's all in Cam/Head/Intake/Carb combo. You should know that with all of the research you have done.

[Brian W]

All I was trying to do by posting the results of my testing was to try and put some real world results on the internet. Instead of this XXX is better cause XXX told me so... I tested it, the results are posted... take the info and use it or not. Never meant to start a pissing match.

My take on the rules is, if you can do it and it passes tech, then it is legal. You have to have a pretty sharp tech man to catch the "good" stuff, and you won't find that kind of tech man at any IMCA race!! No not because they are stupid, just because they don't tech stuff that hard. After all, IMCA racing isn't NASCAR. If you have the $$ and want to spend it and risk selling it for $550 then do so. That is what I tell my customers, and I do far more lower $ stuff then I do high $ stuff.

Define lightweight... IMCA does not... is lightweight under 50lbs? under 49lbs? 48...47..?

[IMCADW]

No I definitely know what you mean by posting the results. It's a clear cut back to back test... And putting the JRM105 is a good start for camshaft but far from what the engine needs.

Yes, if you can do it and it passes tech, then you're legal that time. Drop that expensive crankshaft out at Boone in 2012 and it gets weighed then what? That is my point. You know you'd rather build a legal engine for someone than have an engine running around with worries.

The tech around here isn't that strict either, until you get to Boone. The USRA tech is much more stringent.. but rules clearly state no lightweight crankshafts and no lightening.

[IMCADW]

OEM GM442 Cranks weigh 52 LBS. Anything less would be considered lightweight give or take a pound.

[Brian W]

OEM or OEM replacement steel crankshaft only - cannot be lightened. No aerowing, bullnose, knife edge, undercut or drilling of second or third rod throws.

That is IMCA's rule. It does not say a weight. And they will not take the crank out and weigh it anyway, that would be way too much work. The good crank I use is technically not legal per these rules but it "appears" to be. I.E. It has no holes or machining that you can see that shouldn't be there.

On a side note, I once had a customer that had a set of gas ported pistons in his engine and they did a P&G test and the CID just kept climbing... like 450+ CID. They took the head off and measured B&S and found it to be legal. I thought it might have had something to do with the gas ported pistons and the way a P&G works, don't know for sure but the other three cars they checked that night the P&G worked fine.... they even checked another car after and it worked fine as well, checked the GP engine again and it did the same thing so they pulled the head.