4.2 Stroker build projected HP and Questions

[slithermgs]

Ok, I've put off making this thread for quite a while until I became more familiar with the parts and process required for the build. The goal here is to come up with a projected HP number based on the build I'd like to accomplish so I can plan supporting mods accordingly IE Fuel pump, Injectors, transmission ETC. Most supporting machine work has been taken into consideration, though I'm sure I've over looked something. Ill save my questions for the end.

The Car
2003 split port auto mostly stock. This is my DD so I've got to keep thing reasonable.

The Plan.
I'm planning this in two separate stages as stated above its my DD so there may be some aspects of the build that aren't driven by the need for pure performance. Stage one is to stroke the engine and install as many supporting mods as possible before beginning the second stage which is to install a turbo, supercharger or Nos at this point I'm not sure which one yet. Id like to Keep the stock Auto and just beef it up to handle the HP output. I've done a bit of reading into it and it seems to a reasonable goal at this point. Knowing that I'll be at the very least spraying some Nos I'm going to put in a forged bottom end.

The Build. (all forged where applicable)
4.2 crank
3.8 block bored to match pistons
Push rods
Pistons and rings
Connecting Rods
Bearings Crank, Cam, Main, Etc
Harmonic Balancer
Flex plate
Cam (somewhere in-between mild and wild)
Roller Rockers
Roller Lifters (maybe)

I'm going to gasket match port and polish the heads and upper and lower intake the best I can. I might think about oversized valves in the second stage of the build.

Questions
Obviously the goal here to try to estimate the final HP so I can gather supporting mods. With that being said I've still got a few question.

Will the beefed up tranny hold?
Injector size?
Maf?
Fuel pump?
Igniting coil? (system)
GT rear end wit 4.11 gears?

Also I've thought about doing a Windstar swap instead of the port and polish of the upper intake, what would be the better option in your opinion?

I've tried to write this post out as coherent as I know how. I hope it makes sense lol I left out some obvious Mods like the exhaust and such. I think that's about it what do you all think?

 

[fasterthanyou]

Questions
Obviously the goal here to try to estimate the final HP so I can gather supporting mods. With that being said I've still got a few question.

Will the beefed up tranny hold? 4r70s can take some abuse. Stock will hold up fine.
Injector size? Just go with 60s or 80s, they work just as well as stock for idle quality and support the power you might make later on.
Maf? From your plans, stock seems fine.
Fuel pump? They make 480lph pumps that cost about the same as a focus 310, always opt for the bigger pump.
Igniting coil? (system) stock.
GT rear end wit 4.11 gears? In my experience a 7.5 will hold all the power you'll make but I suppose it doesn't hurt to get an 8.8 diff. They're relatively inexpensive from a junkyard.

Also I've thought about doing a Windstar swap instead of the port and polish of the upper intake, what would be the better option in your opinion? Windstars outperform ported uppers.

 

[slithermgs]

Thanks for the input my friend, I forgot to mention the tune and a throttle body has also been taken into consideration

 

[fasterthanyou]

I'm ignorant in the matter of windstar throttle body compatibility but no one else responded so I'll throw in my 2 cents.

I recall reading somewhere that the 99-04 gt throttle bodys are 70mm and fit the windstar intake. But that could be a load of bologna.

 

[89FoxSC4.3]

I try not to post nothing unless I’m real sure about it because the last thing I want to do is misinform another member, but I measured the one on my 2001 GT back when I had it and it was 65mm.

 

[89FoxSC4.3]

And just from what I have read that you have to use a remote IAC if using the 99-04 GT throttle body.

 

[slithermgs]

I don't think relocating the iac would be much of a problem considering the scope of the project.

 

[89FoxSC4.3]

I don't think relocating the iac would be much of a problem considering the scope of the project.

Nah I don’t think so neither I already kinda got a idea on how I wanna do my Windstar Swap.

 

[slithermgs]

I'm kinda lucky, I've got a machinist and some equipment at my disposal for work lol so brackets and such shouldn't be much of a problem

 

[89FoxSC4.3]

I'm kinda lucky, I've got a machinist and some equipment at my disposal for work lol so brackets and such shouldn't be much of a problem

Yeah you are lucky that’s a big plus right there. I can weld and make my brackets and stuff I had to on my Super Coupe Swap but as far as like full on machine work I have a guy that does it as a reasonable price.

 

[slithermgs]

I'm thinking I'm going to land at about 250 ish at the wheels is my best guess but I could be way off the mark

 

[89FoxSC4.3]

That’s a good number NA to shoot for I think it’s doable, but with that said I think reaching it will depend on your porting skill level and the CR that you are going to be at and getting a good cam recommendation and bringing the combo as a whole together and at the same time if you are gonna try to get a cam to work at your stage two level you was taking about it will suffer some NA but will wake up on the power added you choose, just my 2 cent. Maybe others will chime in also.

 

[slithermgs]

That’s a good number NA to shoot for I think it’s doable, but with that said I think reaching it will depend on your porting skill level and the CR that you are going to be at and getting a good cam recommendation and bringing the combo as a whole together and at the same time if you are gonna try to get a cam to work at your stage two level you was taking about it will suffer some NA but will wake up on the power added you choose, just my 2 cent. Maybe others will chime in also.

I completely agree, my porting skills are untested lol but I'm pretty sure I can pull it off, I'm pretty handy at that sort of stuff, I do experimental stuff for living. Nearly every day is a new project, I start them get them running, hand them off and move on to the next. Back on point though the cam is going to be key. I'm going to talk with a few performance shops in the coming weeks and get some input from them and get a feel for who I want to tune it when I'm finished.

 

[89FoxSC4.3]

I completely agree, my porting skills are untested lol but I'm pretty sure I can pull it off, I'm pretty handy at that sort of stuff, I do experimental stuff for living. Nearly every day is a new project, I start them get them running, hand them off and move on to the next. Back on point though the cam is going to be key. I'm going to talk with a few performance shops in the coming weeks and get some input from them and get a feel for who I want to tune it when I'm finished.

Just do a lot of research if your are going to do the heads yourself. I have done many but never on the sixers and will be doing a lot of research myself. Going to the table with flow numbers if you get them flow tested will help your Cam profiler also. The more information for them the better.

 

[slithermgs]

Heres a crazy thought... I could turbo first lol then build the engine. Trust me I've been looking into this for months now off and on, there's a lot of info scattered around finding it can be quite the task though. I've seen a few videos on port and polishing

 

[89FoxSC4.3]

Yea ive been looking on here a lot too, and there is a lot of good info on here, people are friendly, and Forum is well designed. Even places to talk about unrelated car stuff if you want. I would keep the boost low if you want it to live for any amount of time if you do that due to the factory piston and rod materials and especially if a good many miles on the engine. A good tune is the other thing that’s a must. I got greedy and pushed my Super Coupe mustang build to 15lbs and it popped a head gasket luckily that was all. It kinda acted like a fuse, it popped before it got a piston. I wasn’t running MLS head gaskets I was running the Felpro Super Coupe gaskets. After I pulled the heads off also found out the engine had been built before and was .060 over but still had hypereutectic aftermarket pistons.

 

[slithermgs]

The tune is a subject if got to dive into more I literally spent all day yesterday looking at diy options. And really came up empty handed. Other than some free software heck I couldn't even find what type of connections I would need to hook the ecu/m to a laptop and have a look at the stock tune. I know there options such as the quarter horse and squirt but all that seems a bit excessive to me.

 

[89FoxSC4.3]

Yeah that’s why I left it up to the tuner especially since it was forced induction, but I will be digging and learning more myself. I would like to do my own tuning myself eventually.

 

[fasterthanyou]

You know my vote is for the quarterhorse

Sct is ok, too. But I love the real time tuning of the QH.

 

[slithermgs]

Yeah that’s why I left it up to the tuner especially since it was forced induction, but I will be digging and learning more myself. I would like to do my own tuning myself eventually.

If you find any viable diy options let me know. I'd be very appreciative.