Has anybody done this? Machine shop rebuild and thro in a Comp Cams 127200 and Mahle 10.9:1 pistons (on a 5 speed and 4:10's).

[Jerry Stoneking]

I want to keep the budget on the low, so I would like to hear from somebody that has done this 'set-up' and what the results where.

I will use Kelly's Machine Shop in Phoenix to rebuild my 4.6 3V (they know the ins and outs of this engine), and BTW thro in my Comp Cams 127200's, my Mahle 10.9:1 +.02" pistons, my 5.0 connecting rods, and my Melling high flow pump. Do I get an engine that performs well, and hopefully about 420hp at the crank with all the bolt on's, 5 speed, and 4:10's.

 

[07 Boss]

If your goal is 420 hp I think you would need to go with a bigger cam. What is your displacement with the new rods and pistons?

 

[Jerry Stoneking]

I don't have a good answer for that. The rods are the same dimensionally as stock, not sure piston height difference, and +.020" might make it a 283'ish if everything was equal. The 420hp seemed do'able from the bench racing I have seen.

 

[07 Boss]

Just don't think your going to be close to reaching your goal. You're talking 100 hp with bolt-ons and the mildest of cams. Maybe with a 75 shot of nitrous you might get there. If you want to get to 420 hp your going to have to get the biggest cams possible with head porting and valvetrain work, getting rid of your accessories and go with EPAS, electric water pump, etc. Your not going to get there with under-drives and headers. What is your build plan? List everything you're planning and we may be able to give some direction.

 

[whitmanink]

Just don't think your going to be close to reaching your goal. You're talking 100 hp with bolt-ons and the mildest of cams. Maybe with a 75 shot of nitrous you might get there. If you want to get to 420 hp your going to have to get the biggest cams possible with head porting and valvetrain work, getting rid of your accessories and go with EPAS, electric water pump, etc. Your not going to get there with under-drives and headers. What is your build plan? List everything you're planning and we may be able to give some direction.

agree with everything said here,,
the cams you are installing will add 22hp .. my mutha thumpers add 30hp
and im full bolt on minus electric things (epas, ele water pump ect, )
camed and lito tuned ,, im at about 400 to 403hp ,,
so your cams would need to be changed among other things to really get up there in hp with the cams ( new springs ,porting ,ect)
and all the electric conversion things as well to get to that 420hp

 

[Dino Dino Bambino]

I want to keep the budget on the low, so I would like to hear from somebody that has done this 'set-up' and what the results where.

I will use Kelly's Machine Shop in Phoenix to rebuild my 4.6 3V (they know the ins and outs of this engine), and BTW thro in my Comp Cams 127200's, my Mahle 10.9:1 +.02" pistons, my 5.0 connecting rods, and my Melling high flow pump. Do I get an engine that performs well, and hopefully about 420hp at the crank with all the bolt on's, 5 speed, and 4:10's.

420 crank HP = 370 rear wheel HP

To get there you're going to need all the bolt ons plus ported heads and SPR cams.

NSR cams with stock heads and stock intake manifold with delete plates will only get you in the 340-345 range. Maybe 355-360 if you add the Ford Performance intake manifold with 62mm TB.

Are you sure those 10.9 compression pistons are for a stock displacement motor? I'd expect that level of compression on a stroker.

 

[Jerry Stoneking]

Good thought. I just talked to Mahle tech and these will work with stock everything He ball-parked a calced guestimation of 10.6 hp gain from the compression alone. These engines are high-dollar per horsepower with diminishing returns. It should be ok, my carboned-up '08 engine (in an '05) engine could hold it's own with just about anything stoplight to stoplight. It will just be that much better with a new build, new stock heads with better design (Per Kelly's machine), mild cams, and higher compression, and still keep it on the cheap as possible. GT500 is still an option, but I figure I would be replacing a lot of wore out parts on a $20K 500 with 80-100k miles.

 

[Midlife Crises]

I thought high compression and a mild cam profile was a great way to invite the preignition death rattle. The PCM will respond by pulling ignition timing back.

 

[Jerry Stoneking]

I will research that, I need to know. The tuner said he would take the timing back to a safe position for pump gas, and I don't know how much HP loss that equates to.

 

[Jerry Stoneking]

Just remembered. I did talk to Lito about it, and he was concerned about anything over 11:1.