S5D vs Fortin FRS5

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RodSmith32

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I am looking to upgrade my transaxle and looking for input on the pros and cons of a S5D vs the Fortin FRS5. I have a large 4 seat car with a supercharged LS2. I currently have a Fortin wide gear 4 speed. I understand the FRS5 is pretty close to plug and play but the S5D is substantially cheaper. What do the experts say?
 
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I have the FRS4 and it's noisy... But it works awesome, shifts smoothly, and holds up to a fairly high amount of power. The main drawback is the cost of repair. Gears (especially the R&P) and parts are very expensive. Mine went 7 years before a full rebuild.
 
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RodSmith32 said:
I am looking to upgrade my transaxle and looking for input on the pros and cons of a S5D vs the Fortin FRS5. I have a large 4 seat car with a supercharged LS2. I currently have a Fortin wide gear 4 speed. I understand the FRS5 is pretty close to plug and play but the S5D is substantially cheaper. What do the experts say?
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I would consider this FRS5. Plug and play option is very nice! I had no issues with the FRS5 i had in a prior class 1 car.

https://www.facebook.com/marketplace/item/1096330259065714/?mibextid=wwXIfr
 
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RodSmith32 said:
I am looking to upgrade my transaxle and looking for input on the pros and cons of a S5D vs the Fortin FRS5. I have a large 4 seat car with a supercharged LS2. I currently have a Fortin wide gear 4 speed. I understand the FRS5 is pretty close to plug and play but the S5D is substantially cheaper. What do the experts say?
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Curious, are you changing over for the 5th gear, the sequential shifting, or to handle more power? I have the Fortin 4 speed H-pattern now, I know they're pretty tough.
 
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Something to check I believe the SD5 has a bit wider CV cup face flange to flange distance than the fortin . It may require shorter axles.
Shorter axle means more cv angle / less travel .
 
Actually that was comparing the FRS5 vs Albins . The Fortin is narrower
 
DarkSide said:
Curious, are you changing over for the 5th gear, the sequential shifting, or to handle more power? I have the Fortin 4 speed H-pattern now, I know they're pretty tough.
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I am mainly looking to handle more power. My wide gear has been pretty good, lasted 5 years before a major repair. I actually prefer the traditional shifting pattern but understand the structural benefits of the sequential.
 
If the FRS5 is a plug and play swap I would go that route. Fab and paint adds up quick. I would think the bigger r&p in the D box would move a lot of stuff up and back. That could throw the balance of your car off. I have had really good luck with Fortin trans and they shift the best out of all the transaxles. I know some of the big HP guys have complained about durability but they are running 35.5’s with 2k+ HP. I have a S5D in both of my cars but they started that way and for the money they are the best in my opinion. I have never broken one.
 
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My 4 speed wide gear didn't hold up to more power once I went to a blower.

When I had a stock LS1, I was going 5 years between rebuilds.
Once I added more power, I was taking it out every season, at least once. :)

Pinion head bearing is smallest out of all of the transaxles.
I went through 2 in 1 season.

McMullen isn't a fan of Fortins much any more.
And he sees every type of gear box out there.
Give him a call and he will shoot you straight on his experience.
R&P on my wide gear was $8k.

I do agree the Fortin boxes shift amazing.
I spent the money and did the fabwork to go to the S4.
 
The other part to consider, just going from a S4 to a S4D the trans is much bigger in height
I had to move the trans/CV area up around 2'' then the cv angle got all wacky, and moved the motor higher,
 
J Alper said:
The other part to consider, just going from a S4 to a S4D the trans is much bigger in height
I had to move the trans/CV area up around 2'' then the cv angle got all wacky, and moved the motor higher,
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S4D is only bigger in R&P and bell housing section.
Both S4D and S4 use same gear stack, case, front mount etc.
But I agree, can mess with CV angle etc.
 
Weddle/Mendeola sequential will typically be substantially cheaper to repair/service when the time comes. And more shops are willing to work on them.
 
lincster said:
S4D is only bigger in R&P and bell housing section.
Both S4D and S4 use same gear stack, case, front mount etc.
But I agree, can mess with CV angle etc.
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Will snap a picture have both trans in the shop the Ring and pinion area is much taller on the S4D, than the S4, the gear stack area is the same, around a 1'' bigger going towards the skid plate on the ring and pinion case,
 
J Alper said:
Correct, Lincster thank you for the support. I wish the S4D had a bigger Diff than the S4, only having just the ring and pinion bigger, is it worth it,
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For a new build and minor cost increase, I would say yes.
In my case, a retro fit, I would have had to REALLY cut my car up to get it to fit.
So I went with the S4.
But fair question/point.
 
J Alper said:
Correct, Lincster thank you for the support. I wish the S4D had a bigger Diff than the S4, only having just the ring and pinion bigger, is it worth it,
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The diff gears (spider and side gears) are rarely an issue in the S4/S4D. They are actually the same exact gears in a Fortin open diff for reference.

It's one of the only dis-advantages of the S4D against an Albins as the AGB has the planetary "Torsen" diff that is really strong, and has some limited slip effect under acceleration to get power to both tires compared to the open diff.
 
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