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Discussion Starter · #21 ·
Very interesting modifications:
1.May I ask you why you chose billet conrods? Billet conrods are inheritendly weaker than forged con-rods, so my question is why didn't you choose some custom made forged conrods from carillo or similar.
2. Can you give a number for the weight savings using your pistons and con-rods?
3. Oil consumption: Once finished I would love to get some information on the actual oil consumption of your engine.

Good luck

Andreas
Sorry I have been away. Working kinda hard.

On the billet rods, the 4340 rods are forged prior to machining. The entire billet is forged. The process of forging prior to machining has been an aerospace practice for years because forging after machining causes differential stresses in the material which frequently causes shape changes. The most important consideration in machining after forging is controlling the temperature of the material during machining to prevent overheating the material and reversing the quench and softening the material. It also preserves the grain flow in the crystalline structure of the billet and results in the strongest rod for the weight.

On the manufacturer, it was convenience. I am familiar with 4340 chromoly and 2618 aluminum used in the pistons. Plus, it was Mike Levitas' recommendation and has been used in other rebuilds, and who am I to second guess his vast experience. I've done some first order calculations and the stress in the rods will support RPMs well above 11,000 with strength margin. As I said, I am more than doubling the loads, so I was particularly interested in increasing the stiffness in the rods to minimize cyclic harmonic loads. The H beam is stiffer than the stock I beam. I may be overthinking the problem, but if the rod natural frequency is a low multiple of the RPM, you are loading the crank and wrist pins significantly more than straight inertial load calculations would indicate. I'm sure Carillo rods would be just as good as Carillo has a great reputation.

On the weight, I do not yet have the data on the stock pistons. You can feel the difference holding them, so I would say the weight difference is in the neighborhood on 10%.

On oil usage, the Nickel-silicon carbide coating will take longer to seat the pistons than the stock Lokasil, so I will be tracking oil consumption closely. Because of the slower ring seating, I would expect the engine power to increase slightly above the initial tuning runs.
 

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Discussion Starter · #22 ·
All this talk of Methane injection creates an image in my head of some tube running from the bottom of your seat to your intake and someone handing the driver a bowl of beans... just sayin...


Oh and you can get free Methane injection by driving on the surface of Titan...
You have always been much more capable of producing hot gas than I.
 

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Discussion Starter · #23 ·
Just wait until we implement the memorization requirement! :hilarious:

KenKG, is your car done yet???
Car is not done yet. The methanol pump was not in the kit, so that slowed it down. Plus, I concurred with TPC moving some hot projects in front of me. I can't get back to the shop for a couple of weeks, so I expect it to be very close, if not done. Then I will drive it benignly for a while to make sure the rings seat before I turn her loose.
 

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Discussion Starter · #24 ·
Kenkg,
Where do you get the information that a Meth injection on 91 oct will yield a 100+ rating?

Jose
It is an assumption, Jose. It is based on results I have seen comparing methanol injection dyno results to 110 to 116 octane fuels. I simply assumed that if I can get the same results as 110 when starting with 93 gas, then 100+ should be achievable with 91 gas.

The biggest advantage of ethanol injection is the cooling effect. The boiling point is 148 deg F vice 212 for water and the heat of vaporization is about 7/8 that of water. So it vaporizes much more vigorously than water and absorbs nearly as much heat. Additionally, the freezing point of methanol is minus 144 deg F, so methanol will cool the fuel-air charge to much lower temperatures than water injection.

When I was playing with methanol back in my drag racing days, I would frequently ice up the carburetor in high humidity conditions. In general, horsepower increases 1% for each 10 deg decrease in intake temp, so 100 deg drop, which is not hard for methanol, will produce a 10% horsepower increase. It is also the temp decrease that gives the majority of the anti-knock value increase with a set fuel because the colder intake temp can be compressed more before it reaches auto-ignition temperature (detonation).

In my setup, I do not intend to increase boost to the point of detonation, I intend to let the engine advance the timing to take advantage of the higher net octane rating. That is because I do not want to be dependent on the methanol injection. If I really wanted to build a power machine, I would get into programming the ECU to reduce the gasoline fuel-air ratio and replace the fuel with methanol. And if I really wanted to maximize the power output of the engine, I would run straight methanol with a huge boost pressure.

In my long gone past, I flew radial engine aircraft that supported 52 inches of manifold pressure. That's 38 inches of boost on 115/145 avgas that you can't get any more. Trust me, the first time I ran up a 3,350 cubic inch engine for takeoff with the canopy open, I wasn't really sure whether I was on the threshold of heaven or at the gates of hell. Fifteen seconds later when I convinced myself that I would probably live through it, I knew the answer and grinned so big it hurt.
 
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Discussion Starter · #25 ·
Love the photos, tech, and rebuild. Thanks for sharing. I'd hate to ask what all of this is costing you. But I'm interested because I feel that this is a something that I would want to do.
Let me put it to you this way. I have a car that is superior to a new GT3 in performance and, I believe, handling, for about $30K less than the cost of a GT3, and my cost includes replacing a broken engine. I think I have solved all the warts and weaknesses in my car.

Ask me again in a year, but my suspension and turbo have operated flawlessly for 2 years. The only problem I had was an intake air duct that was rubbing. It was replaced at no charge. I have also received a lot of free advice and insight that was always focused on giving me an honest answer to my question, not their potential to sell me something extra.

If you want to know the price for stuff, I suggest you call and talk to Tom Chan because it depends on what you are including in the total package of things you want. In my case, since the car was torn down, I had an LSD installed, a power steering cooler installed, and the methanol injection system installed and avoided significant labor charges over the cost of the items if I had done them in independent shop visits.
 

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@kenkg

are you sure that the rr rods are made from forged material, eg. machined after forging?
I could not find a single image of a raw forging on their web site, and this together with the american way of agressive marketing made me think that they just machine their rods from standard rectangular billets nad not from forged raw material.

I am very interested in more information on this.
Best regards
Andreas
 

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Discussion Starter · #27 ·
@kenkg

are you sure that the rr rods are made from forged material, eg. machined after forging?
I could not find a single image of a raw forging on their web site, and this together with the american way of agressive marketing made me think that they just machine their rods from standard rectangular billets nad not from forged raw material.

I am very interested in more information on this.
Best regards
Andreas
Andreas, you are right, 4340 is tempered, not forged. My bad. Sloppy use of terminology. I'll clean up my act.
 

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Andreas, you are right, 4340 is tempered, not forged. My bad. Sloppy use of terminology. I'll clean up my act.
Kenkg, you may have been correct with your 1st statment about your R& R rods being forged. 4340 can be forged.

My Pauter rods are E4340 vacuum met chrome moly forgings
(what ever that means lol)
 

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Discussion Starter · #29 ·
Kenkg, you may have been correct with your 1st statment about your R& R rods being forged. 4340 can be forged.

My Pauter rods are E4340 vacuum met chrome moly forgings
(what ever that means lol)
No, my problem is simple familiarity. E4340 is a higher standard of 4340 that includes elevated cleanliness standards. It is aircraft quality steel that is very consistent. Vacuum melting is a method of limiting contaminates and gaseous reactions during the forging process. In my terminology, "forging"
includes all steps of making the alloy and including hardening/toughening \techniques.

4340 is a very strong alloy that has very good fatigue properties. In my application, I think I am using less than 1/3 of the fatigue stress limit and less than 5% of the ultimate stress limit. Yes, you can say that these rods are overdesigned for my application, but I have seen applications where fatigue stress is multiplied by factors (instead of fractions), so I consider a 33% usage factor to account for unknowns is prudent. I want my engine to last a very long time.

R&R, as well as Pauter, uses surface peening to relieve the surface stress caused by machining and to increase the fatigue life of the product.

There are advantages of tempering over hammer forging. Hammer forging increases the probability of inclusions and voids in the part. Of course, a good inspection regimen can detect minor defects and the part can be rejected.

The vast majority of my experience, however, is in aerospace materials and applications, so many of my musings are extensions of my aerospace experiences to my car.
 

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Any more pics?
 

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Excellent thread, great explanation and photos of this build. Am interested to hear how it all turns out!
 

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Discussion Starter · #32 ·
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