Hey there ...
Does anybody know a good source for a set of custom long rods for a 225 slant six ? I need to go about .2" longer than a 198 rod to use the block and pistons I just purchased as a partial project engine. The original builder planned on custom rods but never got that far.
I mocked up the block with a 225 crank, 198 rod and the custom forged 3.5" pistons that came with the block, and I am still down about .230" in the hole at TDC.
The regular sources for custom rods don't have blanks long enough. Any suggestions from somebody that has gone through this ?

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61 Valiant V-200 2dr 225" Hyper pak
66 A-100 pickup 440" mid engine
62 Valiant 2dr 225" drag car"
69 A-100 van 340"
76 Dodge conversion van

Sell the pistons and get new ones. I believe that would be the easiest.

shave the block

" shave the block"

I would have to shave .100" off the block and the head to get about a 9.5 to 1 compression ratio. I'm afraid that might cause head gasket problems.
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"Sell the pistons and get new ones. I believe that would be the easiest."

The block is already bored .100" oversize to match the custom made 3.5" C&E forged pistons and rings that came with it ($$$$). The block also has custom billet steel main caps installed and line bored (more $$$$), so I want to use the block.
The original plan for this motor (before I bought it) was for a 170 crank and even longer custom rods. to run in a supercharged class at bonneville.
I bought it thinking a 225 crank and 198 rods would work, but the C&E pistons have a very low deck height.

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61 Valiant V-200 2dr 225" Hyper pak
66 A-100 pickup 440" mid engine
62 Valiant 2dr 225" drag car"
69 A-100 van 340"
76 Dodge conversion van

0.100" off the block is no problem.

You can call Tom Molnar at K1 technologies (.com) and he can make up any rod you want for about $650/set.

Lou

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Home of Slant6-powered fun machines since 1988

How about Cox Bros? They used to and I think still have lots of slant6 high performance parts..including rods . They had a small catalog available..maybe someone could download the catalog on the website.

For the money of new rods I would suggest finding alternate ways to increase compression. Also, you don't have to run super high compression with a supercharger, however, I'm not going to change your plans or going to assume you already have this penciled out. That being said I would attempt to shave the block and head as that shows no problems with valvetrain or other things. I would suggest something of half block and half head, or equivalent.
My second option for you and the plan for me is with pistons with some tiny compression distances or higher pin holes. I would weld up the combustion chamber and have the head shaved after that. Just the opposite of the spark plug there is a landing that could be welded or closed off to make more of a heart shaped design with the plug and valves. This would actually be my first choice over new rods as research has proved that this increases the quench and efficency as well. I would assume you could achieve your cr without touching the block but don't have all your numbers. Also, someone is coming out with a Cometic (?) head gasket, check the cp piston threads. Might be interesting to you, I have a m90 and 170 that are going to be this next years project for following parrallel lines.

Thanks for all the suggestions. I haven't figured out the "quote" option on this site, so I will try to answer in order.
I will try calling Tom at K1 Technologies and see how practical the custom rods would be. That $650 price tag sounds pretty fair. The custom C&E pistons cost more than that, plus I have 8 pistons (2 spares). Custom long rods would let me dial-in my compression ratio without cutting the block or head, and give me a nice rod-ratio. That was part of the plan for the original builder.
I will look on the Cox Bros website, see what they have.
If the custom rods don't work out I will try my 198 rods and shaving .100" off of the head and the block. That should give me about a 9.5/1 comp ratio. I have shaved heads by that much with no problems, as long as there is enough meat on the block to do the same without head gasket problems, that will work. I will probably just need shorter pushrods and head bolts.
I probably won't be able to take advantage of filling the head for a squish chamber. Even with 198 rods and .100" shaved off the block, the pistons would still be about .130" down in the cylinger at TDC. That is just about the same as a stock 225.
I considered taking advantage of the low compression ratio and using a centrifugal blower. I got some info from The Supercharger Store when they announced their slant six setup. I read two reviews from their slant six customers and it sounded like a lot of money and trouble for a small performance payoff. It sounds tike a turbocharger is a better way to go on a slant motor, but I don't know enough about them to design my own set up. I will stick to carburetion on this motor.
By the way, I have tried various Holleys (390 thru 600 CFM) and Carter/Edelbrock carbs on my performance slant six motors. But I was amazed at the performance improvement from a Road Demon 525 CFM carb. Instant throttle response and great top-end pull on a "streetable" built-up slant six. ... Thanks , V.

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61 Valiant V-200 2dr 225" Hyper pak
66 A-100 pickup 440" mid engine
62 Valiant 2dr 225" drag car"
69 A-100 van 340"
76 Dodge conversion van

By chance if you are still considering to get a custom rod and K1 can't come up with a solution for you please give a call over to Carrillo rods (949)498-1800.
They make rods for the older Jag 6 cyl engine which are much(7.750") longer than the 198 slant rod so I think they could still help you in this area .

Mike @CP