Modern aluminum rods are way different than earlier generations. The main difference being the grade of aluminum used. If they are brand new modern rods they may last indefinitely but if they are old, say 1960's,70's Howards, Mickey Thompsons etc. No way. Those rods had a lifespan of about 50 cycles? (1/4 mile passes) if I remember right.
And thats what I was saying. One of my buddies has old M/T ones in his street driven blown (a moderate street car) since I met him back around 95.
dont do it. been there and with enough heat cycles and pounding on them (work hardening)they will break, not bend. no good reason to run them. still have some for a high revving 283 out of my jr fueler with not much time on them but put 327 rods in it when it went on the street. trade em or save em for racing. you can buy 327 rods or steel ford chevy rods all day long on the bay for 100-150. like the guys are saying you can run them but you have to set up motor real loose, deck ht, rod brgs etc. besides they arent all ways lighter. they are used because the alloy is lighter and therefore can be made bigger(stronger) at equal wt. make scense? i take you allready have them? what are they for and how many miles will you run them? good luck
There are too many cost effective steel rods available today that will give you 90% of the benefits without the fatigue concerns. Unless you lucked into a nice set, why bother? Even then, I would say sell 'em and buy a nice set of light weight steel rods. I just recently found that my stock rods needed resizing. That would have run $120, so I just spent $260 on set of new super stock rods from scat that came with arp bolts, weight matched to 1 gram and sized to +/1 .001". They were slightly heavier than stock, but they have light weight options that a well priced.
Nothing wrong with running a good set of aluminum rods on the street. I dont see why you would want them since there are steel rods out that are way cheaper and stronger and dont weigh much more. I run aluminum heads on my car and i had alot of people telling me a cant. Alot of new cars have aluminum engine parts to save weight now days.
First, they were designed for racing, not street use. That should tell you something right away. I cannot really see the point in taking the risk - is it for bragging rights? How much to pull and tear down the engine when a rod fails vs. what you would spend on a decent set of forged I beams or H beams? I have a couple of ultra rare and exotic '60s/70s race engines - built by a full time pro engine builder/Bonneville racer - came with and he recommended steel rods. Picked up a set of eight new in the box Carillos for $255 on the 'Bay. So why would I want aluminum rods for a motor that will see lots of street duty?
My father has a 12.5 comp ex drag motor that he re cammed for the street. He made god knows how many passes with that motor in the 70's. He kept the motor sold the car and we have used it in several projects since. It is a 30 over 350, balanced, blueprinted, and originally put together by the Hot Rod Shop in Milwaukeee. It uses M/T aluminum rods. We have driven or used that motor on road trips from Wisconsin to Indy, Wis to Florida, and a trip from Wis to AZ. It is currently sitting in storage waiting for the next go around. There are probably somewhere close to 25k miles on it after it left the track. I'm not saying it was the best idea to do this but we used what we had and it worked for us. It personally makes me nervous but he loves it.
You'll end up finding guys who say it's no problem. However, you'll also find a lot of guys who say "50 passes on the strip" "The break, not deform" "they fatigue and you can't tell" and all the rest. It's a street engine... what is the point of running aluminum rods in a street engine? Bragging rights is my guess. You're not racing it, you're not winning money with it, so there is absolutely no reason to run light weight aluminum race rods on a street motor. Aluminum heads and intake are another matter--these will actually make power, and they will lighten the nose of a car significantly (handling and MPG improvements). Aluminum rods just let it rev higher. You're playing Russian Roulette--you may do just fine, or you may get the rod that's finally had enough and breaks. And a broken rod is usually catastrophic for the block. I'm a HUGE believer in spending the money for quality rods in a hot rod engine--they're less likely to break, which means you're more likely to keep your block. -Brad
Your asking a question when the answer is right in front of you? Has your buddy taken his car out of the garage since '95? Frank
Aluminum rods are great for what they were intended for -- large sizes/strength out of a much lighter material. They were and are designed for racing - there is no real reason to run them on the street that I can see . . . why gamble? I found a set of 426 Oliver billet steel rods, had them reworked for my 392 Hemi - now those are a work of damn art! If you can find/afford them - Oliver makes just about the best steel rod out there.
Used aluminum rods taken out of a race engine are wall art. New aluminum rods are safe for 50,000 miles if not over-revved.
I'd like to someday do a budget SBC with 'em, one i can afford to break The deal i've always heard it they stress fatigue, because rods strech. Try bending a piece of alum again and again and you'll see why it is a bad idea Still nothing rev's like an alum rod motor, especially small stroke ones
Not a good idea. My friend had a pontiac with M/T rods in his 40 Ford. We were racing one night and blew 2 rods thru the oil pan. There are much better choices these days, use one of them. Remember no one can see what kind of rod you are using.
The rods I'm looking at are for a Nailhead so it's not like I can call summit and pick up a set of H beams or any other rod's I think I may pick them up for my blower motor that Im going to build for a FED some day Just wanted to know if it was a possible to run them on the street thanks for all the input Tom
Don't know if I remember this correctly, or if it even makes sense, but it seems to me that a local machine shop owner once told me that oil temperature had a lot to do with it? I think that he said keeping the oil temperature from getting too hot would allow them to live longer. Any input on that concept? Later - Karl
Of course aluminum rods will work in a street engine despite what others say. But with the good low cost steel rods out there why monkey with it? The larger aluminum rods can require block grinding for clearance depending on stroke. Special bearings used with a anti rotate pin in the cap adds more money. However, I've used them on on the street no problem. The old saying goes aluminum is 3 times lighter than steel, but 3 times more costly. Something is cool though assembling that engine with aluminum rods. Stay away from the old super-rod aluminum rods. Also, it is not good to go through the "traps" in 1/4 mile letting the engine slow the car with AL rods. The AL rod cap is not as strong as steel for this kind of speed slow-down. That's where brakes can come in handy
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