building the bottom end

2011 gtcs

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I've been thinking of a somewhat budget way to build my bottom end. They're two options I'm thinking of.

First option is to buy the the JDM engineering rods and piston upgrade, looks like the perfect setup but I'd need a machine shop that actually knows mod motors and in AZ that's not common and I don't want to send the engine out of state.
2013-2014 GT500 5.8L ALUMINUM SHORTBLOCK 1200 HP REBUILD KIT
Option two, buy the JDM engineering built short block, this will make everything easy, but 13k plus shipping isn't exactly budget, plus I still need a clutch. The only plus side is I could sell my stock bottom end for a decent amount.
5.8L 4V GT500 Aluminum Shortblock 1200 HP (2013-2014 GT500)
I'm guessing I'm around 780whp, or at least that's what my tuner thinks, I'd like to get the bottom end built so I can really enjoy the car and maybe turn it up more. If anyone has done the upgraded rods and pistons from JDM please chime in.
 

GNBRETT

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Personally Id get some Manley I-Beams bro. They will be a little more but worth it. The rest of the rotating assembly can handle far more than 1200 hp.

Its the rods that are the limiting factor. I dont see the point of putting 1200 hp rods in when u can put 1500 hp rods in it for a few hundred more.
 

Cobra Therapy

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Personally Id get some Manley I-Beams bro. They will be a little more but worth it. The rest of the rotating assembly can handle far more than 1200 hp.

Its the rods that are the limiting factor. I dont see the point of putting 1200 hp rods in when u can put 1500 hp rods in it for a few hundred more.
Let me ask you this,what makes the I beam better than the H beam rods?I would like to know because my car is at the shop now to get bottom end work.I want to be able to shift at 7500 RPM.I am also looking at getting the JDM ENGINEERING superstock cams.
 

Catmonkey

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I've been thinking of a somewhat budget way to build my bottom end. They're two options I'm thinking of.
The problem is the spray bore. In order for new rings to seat, they need a prepped surface to seat the rings. The spray bore may not be thick enough to run a hone down the bore, depending on mileage. Once you get past the plasma liner, you have bare aluminum which won't last long. The solution is to have the block sleeved. Sleeving the block should be a little cheaper than a new aluminum block, but the sleeved block can be honed or bored oversized in the future. However, sleeving your block might increase turn around and down time vs a stocked built short block.

Let me ask you this,what makes the I beam better than the H beam rods?
Manley's I-beams are stronger than their H-beams for the Ford modular, just look at their website regarding horsepower estimates. You can't make a blanket statement that one is better than the other for all aftermarket connecting rods, because it varies from engine to engine, rod to rod and manufacturer to manufacturer. JDM contends the Manley H-beam is virtually indestructible in this platform. I'd discuss it with them. Changing to the I-beam will increase cost. When you look at Manley's power estimates realize the horsepower rating is n/a. You have to be spinning the crap out of the engine to hit those numbers n/a.
 

dale.baker

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I've been thinking of a somewhat budget way to build my bottom end. They're two options I'm thinking of.

First option is to buy the the JDM engineering rods and piston upgrade, looks like the perfect setup but I'd need a machine shop that actually knows mod motors and in AZ that's not common and I don't want to send the engine out of state.
2013-2014 GT500 5.8L ALUMINUM SHORTBLOCK 1200 HP REBUILD KIT
Option two, buy the JDM engineering built short block, this will make everything easy, but 13k plus shipping isn't exactly budget, plus I still need a clutch. The only plus side is I could sell my stock bottom end for a decent amount.
5.8L 4V GT500 Aluminum Shortblock 1200 HP (2013-2014 GT500)
I'm guessing I'm around 780whp, or at least that's what my tuner thinks, I'd like to get the bottom end built so I can really enjoy the car and maybe turn it up more. If anyone has done the upgraded rods and pistons rom JDM please chime in.
I personally had JDM design, build, and tune on site my entire engine package. I removed and re installed the engine and broke it in. Jim promised me 800 RWHP before the build, Dyno'd 806 RWHP at 7600 RPM. You can see my car on the dyno on their web site. Five years later the car gets 19.5mpg with no issues and is a ton of fun to drive (See sig for mods). Lastly don't think you will hook up this amount of power without serious suspension modifications and drag tires with substantial side wall (15-17"). To answer your question I would send your complete motor to JDM and let them build it. Install it yourself. Have JDM recommend a local shop to work with Jim Sr. to remote dyno tune the car. As for rods the JDM/Manley H Beams have been used for years without issue on many of their sponsored Cobra Jet cars. If you have the extra money possibly the I-Beam rods will handle more than 1400 RWHP more reliably?Just my 2 cents. Hope this info helps.
 
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GNBRETT

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Its more about where the material is located on each beam. Both will work in most applications and both can be designed to work well.

The H-bean is stronger while under high cylinder pressure.

Most high horsepower Boosted cars will have I-Beams. H-beams are heavier and great in high revving engines like in a NA motor.

There are many factors to consider but in general any high horsepower Ford motor build by MMR, MPR or FF Racing will have I-beams located inside the motor. Im sure there are a few exceptions and some companies make a hybrid style rod that uses both the H-Beam and I-Beam benefits.

Cams will give u more RPM. Just remember RPM has to do with duration and the smaller the duration the more power u see down low but as move the power curve higher up in the RPM range u loose some of the low end power.

Let me ask you this,what makes the I beam better than the H beam rods?I would like to know because my car is at the shop now to get bottom end work.I want to be able to shift at 7500 RPM.I am also looking at getting the JDM ENGINEERING superstock cams.
 

Cobra Therapy

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Its more about where the material is located on each beam. Both will work in most applications and both can be designed to work well.

The H-bean is stronger while under high cylinder pressure.

Most high horsepower Boosted cars will have I-Beams. H-beams are heavier and great in high revving engines like in a NA motor.

There are many factors to consider but in general any high horsepower Ford motor build by MMR, MPR or FF Racing will have I-beams located inside the motor. Im sure there are a few exceptions and some companies make a hybrid style rod that uses both the H-Beam and I-Beam benefits.

Cams will give u more RPM. Just remember RPM has to do with duration and the smaller the duration the more power u see down low but as move the power curve higher up in the RPM range u loose some of the low end power.
Thank you for the info.
 

2011 gtcs

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The problem is the spray bore. In order for new rings to seat, they need a prepped surface to seat the rings. The spray bore may not be thick enough to run a hone down the bore, depending on mileage. Once you get past the plasma liner, you have bare aluminum which won't last long. The solution is to have the block sleeved. Sleeving the block should be a little cheaper than a new aluminum block, but the sleeved block can be honed or bored oversized in the future. However, sleeving your block might increase turn around and down time vs a stocked built short block.


Manley's I-beams are stronger than their H-beams for the Ford modular, just look at their website regarding horsepower estimates. You can't make a blanket statement that one is better than the other for all aftermarket connecting rods, because it varies from engine to engine, rod to rod and manufacturer to manufacturer. JDM contends the Manley H-beam is virtually indestructible in this platform. I'd discuss it with them. Changing to the I-beam will increase cost. When you look at Manley's power estimates realize the horsepower rating is n/a. You have to be spinning the crap out of the engine to hit those numbers n/a.
That's why i was unsure if the JDM rods and piston kit would work, my car is about to hit 11k miles so I'm sure I don't have a lot of plasma liner available, I'd rather just buy the built short block from them, but 13k isn't easy to drop. I feel like there isn't a easy way to do this without spending big money.

I personally had JDM design, build, and tune on site my entire engine package. I removed and re installed the engine and broke it in. Jim promised me 800 RWHP before the build, Dyno'd 806 RWHP at 7600 RPM. You can see my car on the dyno on their web site. Three and a half years later the car gets 19.5mpg with no issues and is a ton of fun to drive (See sig for mods). Lastly don't think you will hook up this amount of power without serious suspension modifications and drag tires with substantial side wall (15-17"). To answer your question I would send your complete motor to JDM and let them build it. Install it yourself. Have JDM recommend a local shop to work with Jim Sr. to remote dyno tune the car. As for rods the JDM/Manley H Beams have been used for years without issue on many of their sponsored Cobra Jet cars. If you have the extra money possibly the I-Beam rods will handle more than 1400 RWHP more reliably?Just my 2 cents. Hope this info helps.

That's awesome to hear, I've always heard great things about JDM and I have faith that there short block would be perfect for me, just comes down to dropping the cash.
 

Beercules

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That's why i was unsure if the JDM rods and piston kit would work, my car is about to hit 11k miles so I'm sure I don't have a lot of plasma liner available, I'd rather just buy the built short block from them, but 13k isn't easy to drop. I feel like there isn't a easy way to do this without spending big money.


When this car first came out I read where Ford tested their plasma liner (PTWA) to the equivalent of 100k miles, it still had a crosshatch. I've read where sometimes the PTWA is no longer round, so keep that in mind. You just never know until you open it and have someone inspect it.
Also, it might give you more confidence to know the GT-R uses PTWA from the same German company (Honsel).
 

RBB

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That's why i was unsure if the JDM rods and piston kit would work, my car is about to hit 11k miles so I'm sure I don't have a lot of plasma liner available, I'd rather just buy the built short block from them, but 13k isn't easy to drop. I feel like there isn't a easy way to do this without spending big money.



That's awesome to hear, I've always heard great things about JDM and I have faith that there short block would be perfect for me, just comes down to dropping the cash.
I think with only 11K miles your plasma liners would be just fine to use. From what I understand you'd have to have pretty high mileage on them to see the type of wear that would make the new hone impossible. I don't think you're anywhere near the type of mileage where that would be an issue.

I'd give Jim Jr. at JDM a call and speak to him about it. As dale said, they're a great shop to work with and always take the time to respond to your questions. I bought one of their shortblocks and took my heads up to the shop. Had them assemble the complete longblock up there and ship it to me. Pretty painless, would definitely do business with them again.
 

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