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Discussion Starter #1
The Fiat 124 seems to only have the Tork forged rods and pistons as an option, but those are quite expensive. However, we share our engine with the fiat 500s for the most part. My question is, would rods and pistons such as these fit our cars?


To be honest, if these do I have no clue why anyone would buy the ones from Tork. This set seems to support even higher horsies than the Tork one and for less than 1/2 of the price. Furthermore, I feel that this has not been discussed yet, and knowing the answer to this question would help people who are trying to build out their spiders to the fullest while keeping the engine safe.
 

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The Fiat 124 seems to only have the Tork forged rods and pistons as an option, but those are quite expensive. However, we share our engine with the fiat 500s for the most part. My question is, would rods and pistons such as these fit our cars?


To be honest, if these do I have no clue why anyone would buy the ones from Tork. This set seems to support even higher horsies than the Tork one and for less than 1/2 of the price. Furthermore, I feel that this has not been discussed yet, and knowing the answer to this question would help people who are trying to build out their spiders to the fullest while keeping the engine safe.


this is what I suggest
I spent less than all those kits on my CP Carrillo/Arias custom 72.5mm oversized pistons and Molnar rods. The Pistons, rings, pins were under $700 and the Molnar rods were around $440. Granted, I had to pay to have the block overbored to 72.5mm but I would suggest talking with Carrillo to personally about a 72mm drop in set.
 

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Calehedron identified suppliers who are known for quality parts. They’re known and respected.
There are some happy Tork customers on the forum, but I wouldn’t buy anything from him, especially these parts.
Best regards
Pete
 

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Discussion Starter #5
I spent less than all those kits on my CP Carrillo/Arias custom 72.5mm oversized pistons and Molnar rods. The Pistons, rings, pins were under $700 and the Molnar rods were around $440. Granted, I had to pay to have the block overbored to 72.5mm but I would suggest talking with Carrillo to personally about a 72mm drop in set.
Interesting, after posting this an older article came up that discusses these arias pistons. How does overboring work, and would that be as simple as paying someone to bore out my engine a little bit or is there a bit more to it than that? Also, in the end, how do you like the difference of the larger pistons? Im thinking, over the course of the next few years, I want my spider to be running e85 on the NGEN 11 billet turbo and I think it could be a good idea to put in forged pistons because the power output should be pretty good between those two and the tune accompanying them. At what point do you even think it makes sense to replace our pistons?
 

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Interesting, after posting this an older article came up that discusses these arias pistons. How does overboring work, and would that be as simple as paying someone to bore out my engine a little bit or is there a bit more to it than that? Also, in the end, how do you like the difference of the larger pistons? Im thinking, over the course of the next few years, I want my spider to be running e85 on the NGEN 11 billet turbo and I think it could be a good idea to put in forged pistons because the power output should be pretty good between those two and the tune accompanying them. At what point do you even think it makes sense to replace our pistons?
If you just want to add the .5mm, any engine machine shop can do that work. You will also need to modify the head gasket to fit over the larger cylinders. Greg is the only one with the pistons in a running engine right now, I am about 50% complete on my rebuild installation. They are a slightly lower compression ratio but almost no loss even off boost due to the other flow enhancements to the head and turbo manifold, rest is made up in the tune. The other big factor in replacing the pistons is the rings. Setting the end gap properly for higher compression and heat so they don't bind up on expansion and roll or rip the top of the piston off AGAIN.

If you plan on surpassing 300BHP/240WHP then I would replace the pistons and rings for sure, rods are more of a while I was in there thing and stronger is better for safe operation.
 

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My car is running EC 9.3:1 pistons with an overbore giving me 1406ccs, up from 1368.

That displacement adds very little power, but my thinking is that it helps offset the slight loss in power from the compression drop from the stock 9.8:1. The pistons are made by Arias. I have about 500 miles on the pistons, and I feel my thinking was sound, I don't really notice any loss in power, boost threshold or anything else, although the math says I certainly lost a little bit.

The compression drop should allow me to run a lot more boost, about 4 pounds more for a given level of knock protection. In other words, if 25 pounds is normally the safe limit with a good intake, intercooler and fuel, then I should be able to shove in 29psi. Plus the pistons are much stronger than stock.

All that said, my engine isn't really ready for prime time yet, I'm still working on development, which is why EC has not released the pistons. My plan is to run a peak boost of 32psi with water injection, these pistons should allow me to do that easily, but I haven't done it yet.

If for some reason that doesn't work out, then there isn't much point in dropping the compression, as we can run in the high 20s with water injection and 9.8:1 anyway.

The Wossner pistons are good, but not strong enough for some of the things I want to do, plus they only make them in 9.8:1. I'm not saying they are not strong, they are, and will handle a lot of power, but are much more likely to fail if the engine knocks, in that regard they are a lot like the stock pistons. The stock pistons will handle a lot of power as well, we have seen over 250whp on the stock pistons, but it's very risky, not because of the power, so much as the proximity to knock. Stronger pistons and lower compression solves both problems.

Greg

P.S. I want to mention again that EC will not release these pistons until our testing is complete and the performance data is solid. I see a lot of vendors selling pistons for these cars, pistons they have never actually installed. caveat emptor
 

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Discussion Starter #8
My car is running EC 9.3:1 pistons with an overbore giving me 1406ccs, up from 1368.

That displacement adds very little power, but my thinking is that it helps offset the slight loss in power from the compression drop from the stock 9.8:1. The pistons are made by Arias. I have about 500 miles on the pistons, and I feel my thinking was sound, I don't really notice any loss in power, boost threshold or anything else, although the math says I certainly lost a little bit.

The compression drop should allow me to run a lot more boost, about 4 pounds more for a given level of knock protection. In other words, if 25 pounds is normally the safe limit with a good intake, intercooler and fuel, then I should be able to shove in 29psi. Plus the pistons are much stronger than stock.

All that said, my engine isn't really ready for prime time yet, I'm still working on development, which is why EC has not released the pistons. My plan is to run a peak boost of 32psi with water injection, these pistons should allow me to do that easily, but I haven't done it yet.

If for some reason that doesn't work out, then there isn't much point in dropping the compression, as we can run in the high 20s with water injection and 9.8:1 anyway.

The Wossner pistons are good, but not strong enough for some of the things I want to do, plus they only make them in 9.8:1. I'm not saying they are not strong, they are, and will handle a lot of power, but are much more likely to fail if the engine knocks, in that regard they are a lot like the stock pistons. The stock pistons will handle a lot of power as well, we have seen over 250whp on the stock pistons, but it's very risky, not because of the power, so much as the proximity to knock. Stronger pistons and lower compression solves both problems.

Greg

P.S. I want to mention again that EC will not release these pistons until our testing is complete and the performance data is solid. I see a lot of vendors selling pistons for these cars, pistons they have never actually installed. caveat emptor
Sorry for the slow response, I’m quite busy and don’t have much time to be on the forum. It’s super cool to know that EC has rods and pistons in the works! So, if I understand you correctly, for now boring the engine dropped your power, but once you are ready to support up to 32 psi it should make more, correct? From what you say, I don’t think I would want to bore the engine. I feel if I decided to go with something like the 1772 turbo to really try and maximize horsepower it could make sense, since I would already have to get more specialized parts at that point anyways. However, both you and Calhedron make it obvious that upgrading the pistons is worth it. To get a set from Arias, would I just contact them with specifications for the pistons and they would custom make them? Also, how long would you say it could take for EC to release pistons and rods, and do you think you will ever want to carry the oversized pistons online for people who want to bore their engines? If you can’t answer those questions, that’s great too! Thank both you and Calhedron for the amazing information, you guys are always responding to everyone’s posts with the most useful things.
 

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Discussion Starter #9
If you just want to add the .5mm, any engine machine shop can do that work. You will also need to modify the head gasket to fit over the larger cylinders. Greg is the only one with the pistons in a running engine right now, I am about 50% complete on my rebuild installation. They are a slightly lower compression ratio but almost no loss even off boost due to the other flow enhancements to the head and turbo manifold, rest is made up in the tune. The other big factor in replacing the pistons is the rings. Setting the end gap properly for higher compression and heat so they don't bind up on expansion and roll or rip the top of the piston off AGAIN.

If you plan on surpassing 300BHP/240WHP then I would replace the pistons and rings for sure, rods are more of a while I was in there thing and stronger is better for safe operation.
I’m somewhat confused on why boring out the cylinders would reduce power. I can understand that there would be lower compression, but does it just have a higher top speed because it can support more boost or something?
 

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I’m somewhat confused on why boring out the cylinders would reduce power. I can understand that there would be lower compression, but does it just have a higher top speed because it can support more boost or something?
It's not the overbore itself, but the fact that Greg designed the pistons for a lower C/R at .5mm larger than the stock ones so just mathmatically it is less power at same boost level. They could be designed to be 9.8 or whatever at 72.5mm if you wanted. Because of the lower starting C/R, more boost can be used across the range due to the strength of the new parts and perfectly installed rings. He has also come up with a design for porting the head on both the intake and exhaust sides and added the ported turbo manifold that makes up more of the cylinder loss if you go that route to be close to even but no hard numbers on that direct comparison yet.

I had to overbore because I melted a couple pistons, had shrapnel everywhere, and needed to resurface the cylinder walls so going up to the 72.5mm Greg designed worked perfectly for me at just the right time so I jumped in on his buy from Arias. I thought about the Carrillo Rods, there would have been no chance for clearance/tolerance issues being made as a set with the pistons but I could not justify the cost for them. I don't need a rod set that can withstand 1000+HP for $1600. The Molnar rods are more than durable enough for 400HP at ~1/3 the cost and hopefully after the feedback and rework of the pin bearings on my set, that won't happen again to anyone else.
 

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As Calehedron said, it's not the overbore that causes a loss in power, it's the drop in compression. The overbore slightly increases power. Overall on the stock tune the engine is more powerful than stock with the addition of the lightly ported head.

The reason for doing it this way is so I can ultimately make more power by running a lot more boost than I could with stock compression levels without having to go to alternative fuels.

Yes, we plan to offer these in standard compression as well, and in two sizes of overbore, 1378 and 1406 (stock is 1368). We will not have these made for the stock bore because the stock blocks vary a bit, we can't get the right piston to wall clearance by matching the piston to the block, it has to be the other way around.

On the subject of Rods, the Molnar rods are just fine. We may or may not carry them, but I can say that at this point they are good to go right off the shelf. The set Calehedron sent me were NOT OK, but I worked with Molnar correcting the problem and they are straightened out now. I traced their origin to figure out how they go screwed up, and when I figured out which vendor was responsible, well, I wasn't surprised.

Again, all this with pistons is just "the plan". Until I put up the dyno and acceleration data it's all subject to change. In regards to rods, buying them direct from Molnar is probably an option, if not I'll get EC to carry them. Pistons are a different story, there are factors with pistons in this engine that I'm not posting here. I strongly suggest getting pistons from EC.

Greg
 

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Discussion Starter #12
As Calehedron said, it's not the overbore that causes a loss in power, it's the drop in compression. The overbore slightly increases power. Overall on the stock tune the engine is more powerful than stock with the addition of the lightly ported head.

The reason for doing it this way is so I can ultimately make more power by running a lot more boost than I could with stock compression levels without having to go to alternative fuels.

Yes, we plan to offer these in standard compression as well, and in two sizes of overbore, 1378 and 1406 (stock is 1368). We will not have these made for the stock bore because the stock blocks vary a bit, we can't get the right piston to wall clearance by matching the piston to the block, it has to be the other way around.

On the subject of Rods, the Molnar rods are just fine. We may or may not carry them, but I can say that at this point they are good to go right off the shelf. The set Calehedron sent me were NOT OK, but I worked with Molnar correcting the problem and they are straightened out now. I traced their origin to figure out how they go screwed up, and when I figured out which vendor was responsible, well, I wasn't surprised.

Again, all this with pistons is just "the plan". Until I put up the dyno and acceleration data it's all subject to change. In regards to rods, buying them direct from Molnar is probably an option, if not I'll get EC to carry them. Pistons are a different story, there are factors with pistons in this engine that I'm not posting here. I strongly suggest getting pistons from EC.

Greg
As Calehedron said, it's not the overbore that causes a loss in power, it's the drop in compression. The overbore slightly increases power. Overall on the stock tune the engine is more powerful than stock with the addition of the lightly ported head.

The reason for doing it this way is so I can ultimately make more power by running a lot more boost than I could with stock compression levels without having to go to alternative fuels.

Yes, we plan to offer these in standard compression as well, and in two sizes of overbore, 1378 and 1406 (stock is 1368). We will not have these made for the stock bore because the stock blocks vary a bit, we can't get the right piston to wall clearance by matching the piston to the block, it has to be the other way around.

On the subject of Rods, the Molnar rods are just fine. We may or may not carry them, but I can say that at this point they are good to go right off the shelf. The set Calehedron sent me were NOT OK, but I worked with Molnar correcting the problem and they are straightened out now. I traced their origin to figure out how they go screwed up, and when I figured out which vendor was responsible, well, I wasn't surprised.

Again, all this with pistons is just "the plan". Until I put up the dyno and acceleration data it's all subject to change. In regards to rods, buying them direct from Molnar is probably an option, if not I'll get EC to carry them. Pistons are a different story, there are factors with pistons in this engine that I'm not posting here. I strongly suggest getting pistons from EC.

Greg
Im very excited for when those are in stock. I see what you and Calhedron are saying about the cylinder size and compression ratio, and that all makes sense. Overall, from what you guys are saying I think that boring the engine and upgrading the internals seems like something I will need to do before swapping my turbo. My last question is kind of unrelated, but it also has to do with an expensive engine internal that can change the behavior of your engine. How is the performance cam from C&B, if you guys have any comments about it now? I read through the older article that you guys contributed in about the cam. Based on the dyno charts in the article and what was said the cam was not worth the money. At this point, do you guys have anything new to add on the cams, or is the consensus still the same? In theory, the higher redline, extra horsepower, and more aggressive feel of the cam all sound very exciting and like it would pair well with the lower compression pistons. Based on what I have been able to find it just doesn't seem worth it sadly, but I'm hoping that by now some more tuning and testing has been done.
 

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The previous cam sold by EC was for the stock setup. With changes to the porting of the head and turbo manifold, a new one has to be tested to find what works best. I absolutely will change mine out at some point but it has to be identified first.
 

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Discussion Starter #14
The previous cam sold by EC was for the stock setup. With changes to the porting of the head and turbo manifold, a new one has to be tested to find what works best. I absolutely will change mine out at some point but it has to be identified first.
The C&B cam was made for an otherwise stock car? I feel like I am misunderstanding that because if that were the case I feel like it would be a pretty terrible purchase. In any case, the C&B cam sounded like a nightmare to install anyways. Would searching for a different solution for the cam mean custom cam grinding, or possibly a custom order from a cam manufacturer?
Thanks for all the info you guys, I’ve been researching the market for 124 modifications and whenever I’ve been stuck on what something does or what performs best you two have always been able to clear things up.
Happy thanksgiving,
Adam
 

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I like the C&B cam, but I don't think the bang for the buck is there. We have tried hotter cams and I haven't been happy with them either. I'm trying to get that bang for the buck balance right which I believe I now have figured out, but it's not nearly ready for release.

Greg
 

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I like the C&B cam, but I don't think the bang for the buck is there. We have tried hotter cams and I haven't been happy with them either. I'm trying to get that bang for the buck balance right which I believe I now have figured out, but it's not nearly ready for release.

Greg
That’s super exciting and great to hear! I’m definitely gonna be on the lookout for the pistons and cam when they get released. Well, I’m glad to know that the C&B cam isn’t something I’m interested in.
 

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I like the C&B cam, but I don't think the bang for the buck is there. We have tried hotter cams and I haven't been happy with them either. I'm trying to get that bang for the buck balance right which I believe I now have figured out, but it's not nearly ready for release.

Greg
You know what else would be cool? If you guys made multiair springs to compete with Tork's. Im interested in those, but having more than just one option on the market would be awesome. Any plans for that?
 

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Really? Is it a bad idea to give them a try? I’m interested because they advertise small gains and smoother operation for a small cost, but if it’s been disproven or could potentially mess up my engine I’d want to avoid them.
There's a whole bunch of theories here:


I wouldn't put them in my car until I'd read that whole discussion in its entirety and was sure I understood the basic concepts behind what everyone was saying, personally. YMMV.
 
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