Engine I-beam V. H-beam Connecting Rods

I just dropped off my 351 block off at the machinist to have her machined for the project I'm working on...I'm stroking her out to a 408. I'm going to use a Scat forged rotating assembly, but I don't know if I should run I-beam or H-beam connecting rods. With the flat top pistons and TrickFlow 205 11Rs w/66cc combustion chambers I figured I'd run in the range of 11-11.5:1 CR (also having a custom one-off cam ground). I don't think it would be out of the question that it would see a nitrous system (prolly a 150-200hp shot) or maybe even forced induction...but not right away. I'd really like it stay N/A. Each Scat forged kit with I-beams or H-beams aren't too far off in price, maybe $200-$300 dollar difference. I don't see the crank ever spinning more than 65/6600 RPMs. Should I say eff it, the I-beams are fine, or should I spring for the H-beams? I think with the set up I've kinda been planning, it's gonna make about 600 RWHP without the nitrous. Please advise...I don't want my motor grenading because my connecting rods sucked.

Yeah, it's not gonna break the bank or anything. I was just wanting to know if there were pros and cons to each of H-beam is just what you want to go with for big power. Thanks for the advice.

FastDriver said:

It's not the style that matters, IMO. Oliver makes arguably the best rods in the business and they only produce I-beam rods. Many other companies believe in the virtues of H-beams and produce rods that rival Oliver.

Scat makes some really good stuff. Why don't you contact them and take their advice?

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Took your advice and called Scat...the tech I talked to said the I-beams are good to about 700hp N/A. He said anytime you go north of that with a power adder (which I plan to run nitrous) you should really go with the H-beam. I think my parts I've chosen for this build will put me at about 600hp N/A...with the gas, a little over 700hp. Might as well build it strong and not need it than to build it weak and wish you built it strong when you put a rod through the oil pan.

FastDriver said:

Excellent! I wouldn't confuse advice about their I-beam rods for the I-beam rods of other manufacturer's though. You'll find oliver billet I-beams in some of the baddest motors on the planet.

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Yeah, I was looking at some of those billet I-beams and I really don't have the budget for $2K connecting rods...one day though, I'll build a complete billet motor, but I need a couple of raises at my job to get there . I've always known H-beam is the way I need to go, but I was trying to cut corners which is something I said I wasn't going to do with this motor. I was also looking at direct-port nitrous systems (which are awesome looking, I think), but I'd hate to drill into that Super Vic or TFS R-series carb-style manifild...but dome all that plumbing looks so awesome!