Forged Internals Build 10:1 vs 9:1 compression pistons????

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802SHO

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I have a partial quote for a rwd drive conversion on the SHO with an LS setup which is cheaper than the F150 hardware minus the electronic bits....

The shop called me back after a couple of days after they hit $40K in fab labor / regular labor and parts..

I said we can pull the plug...

Biggest issues were gonna be mounting a rear end that could handle the torque. Custom mount points, custom bracing, custom axles, brakes, etc etc etc...
You can make anything custom by taking away from it (cutting) or adding (welding). Not like it's going to be made from scratch. Of all the vehicles on the road there's no need to overthink an axle/brake/wheel assembly. Or transmission. 40k? Partial estimate? Grossly inflated. Huh that's weird...20k tax? What's the tax rate? 100%?
 

StealBlueSho

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So it would be easier to body swap a F150 you are basically saying?

No. I was referencing an LS setup cause they are dirt cheap... F150 would be more expensive...

F150 block would technically fit... you would have to push the firewall back and do a shit ton of other fab work..

But if you are gonna do that, you are also gonna need to a build the support in the rear to mount the rear diff that can handle the torque you wanna throw at it...

Our cars are not a full frame... where as the F150’s are...

Easier from the standpoint of mating the canbus so you can keep all the electronics inside off individual switches.
 

StealBlueSho

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You can make anything custom by taking away from it (cutting) or adding (welding). Not like it's going to be made from scratch. Of all the vehicles on the road there's no need to overthink an axle/brake/wheel assembly. Or transmission. 40k? Partial estimate? Grossly inflated. Huh that's weird...20k tax? What's the tax rate? 100%?

Probably grossly inflated, but I don’t have the skill to do all that work... you start thinking about all the work needed, it adds up...

If you have the skills to do it yourself, then sure, it can be done a lot cheaper.. since your saving all the money on labor...

There is fusion with a coyote swap. So it’s possible.
 

802SHO

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Probably grossly inflated, but I don’t have the skill to do all that work... you start thinking about all the work needed, it adds up...

If you have the skills to do it yourself, then sure, it can be done a lot cheaper.. since your saving all the money on labor...

There is fusion with a coyote swap. So it’s possible.
I agree that the trans would be better off forgotten and a swap would be worth wild. Like by the time someone does do this....it'll be like the best thing ever......it's so common place others would shrug and wonder what the accomplishment was.
 

StealBlueSho

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I agree that the trans would be better off forgotten and a swap would be worth wild. Like by the time someone does do this....it'll be like the best thing ever......it's so common place others would shrug and wonder what the accomplishment was.

Yup, the end result of the discussion was that it was 100% doable, but it would be very costly, and it would be just for the uniqueness and a custom one off. He said you usually see that stuff come out of shops where the owner does the work to his own car.

Ultimately it would be better to start off with a platform that already has a good base.

But ultimately back on track...

I wanna hear more about owners in the 3.5 EB world dropping to 9:1 compression and the results?
 

Nova

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You could always put a GTR drive train into the SHO. Make it a Ford Taurus GTR.

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mattr66

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I'll be short here.
1. Have realistic goals for the platform (car itself)... trans, driveshafts etc.
2. This is not a big boost coyote that lives life at wot most of the time.
3. If you are running at mbt timing at full boost now (stock engine) on e30, there is no reason to lower the compression.
4. You should focus your engine build on increasing VE rpm range so you can keep the same torque limit (imposed by the drivetrain) and make more hp at a high rpms. 19 pounds of boost with properly set up cams and valvetrain will make 600 whp at 6200 rpms and keep torque at a sane level to protect the rest of the car. Matt@Gearhead
 

stripSHO

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I'll be short here.
1. Have realistic goals for the platform (car itself)... trans, driveshafts etc.
2. This is not a big boost coyote that lives life at wot most of the time.
3. If you are running at mbt timing at full boost now (stock engine) on e30, there is no reason to lower the compression.
4. You should focus your engine build on increasing VE rpm range so you can keep the same torque limit (imposed by the drivetrain) and make more hp at a high rpms. 19 pounds of boost with properly set up cams and valvetrain will make 600 whp at 6200 rpms and keep torque at a sane level to protect the rest of the car. Matt@Gearhead
Is anyone actually achieving MBT on e30? Most I've seen mentioned is 23 or 24 degrees. And what about those who are turned off by the thought of hand mixing their gas all the time? Would you say 9:1 works better with pump gas?
 

mattr66

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Is anyone actually achieving MBT on e30? Most I've seen mentioned is 23 or 24 degrees. And what about those who are turned off by the thought of hand mixing their gas all the time? Would you say 9:1 works better with pump gas?
Let me specify.... PE30 (Premium 93 cut with E85) you can achieve MBT if you aren't being stupid and trying to achieve that last 10 hp and violating the engineering preignition design limits.

If you are on pump gas, then you aren't pushing the limits of anything, so why **** your efficiency running lower compression and your ability to take advantage of good fuel at the track.
 

stripSHO

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I suppose we have different definitions of MBT then. But points well taken!
 

mattr66

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I suppose we have different definitions of MBT then. But points well taken!
MBT should be understood as "max brake torque without exponential peak pressure gain" not simply timing where the most power is made

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mrhighcaliber

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Yup, the end result of the discussion was that it was 100% doable, but it would be very costly, and it would be just for the uniqueness and a custom one off. He said you usually see that stuff come out of shops where the owner does the work to his own car.

Ultimately it would be better to start off with a platform that already has a good base.

But ultimately back on track...

I wanna hear more about owners in the 3.5 EB world dropping to 9:1 compression and the results?
This is what I want...or wanted as well, To see or hear from real world people who have run 9:1 pistons in a ecoboost 3.5, f150 or car.

This is certainly a fun topic to kick around. But the efficiency loss of going to 9:1 turned me off from it quite a bit. I'm concluding that my power goals of ~650hp crank isn't high enough to require lower comp pistons. If I was planing to make 800-1000hp, 9:1 makes good sense with probably 35psi boost to get there.

But my goal is ~650hp crank/ 550awhp, ~20psi.

I'm still very interested in seeing a 9:1 build and it's performance characteristics vs what we know from 10:1.


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mrhighcaliber

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I'll be short here.
1. Have realistic goals for the platform (car itself)... trans, driveshafts etc.
2. This is not a big boost coyote that lives life at wot most of the time.
3. If you are running at mbt timing at full boost now (stock engine) on e30, there is no reason to lower the compression.
4. You should focus your engine build on increasing VE rpm range so you can keep the same torque limit (imposed by the drivetrain) and make more hp at a high rpms. 19 pounds of boost with properly set up cams and valvetrain will make 600 whp at 6200 rpms and keep torque at a sane level to protect the rest of the car. Matt@Gearhead
Matt66 of GH has spoken. Thanks Matt. I had a drafted email that was going to be send today on this topic. Until I saw your posts. 10:1 it is. I'm screen shotting the points you listed. Especially about increasing VE at high rpms.

Have our stock cams profiles proven to be a hindrance at higher rpms or boost levels?

A set of cams profiled for performance with 2 more HPFP lobes (6 vs 4) should give the stock HPFP the same effect as the xdi35. ~$1600 on a set of cams would potentialy **** 2birds with 1 stone.

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mattr66

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Matt66 of GH has spoken. Thanks Matt. I had a drafted email that was going to be send today on this topic. Until I saw your posts. 10:1 it is. I'm screen shotting the points you listed. Especially about increasing VE at high rpms.

Have our stock cams profiles proven to be a hindrance at higher rpms or boost levels?

A set of cams profiled for performance with 2 more HPFP lobes (6 vs 4) should give the stock HPFP the same effect as the xdi35. ~$1600 on a set of cams would potentialy **** 2birds with 1 stone.

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The stock cams are so small, im surprised it makes power past 4500 rpms at all... That's problem 1. As far as the pump lobe goes, our 4 lobe design actually has an rpm limitation compared to the truck 3 lobe design. Even if you could, you wouldn't want to go above the 4 lobe design. Just adding lift will satisfy your fuel goals.

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