4.6 2V Swap Progress

yeah it is. but not enough to make a difference in my opinion. and I got a really good deal on the engine, trans, ecm and wiring harness.
 
Only time will tell what we can get out of a NPI ported head.

I'll try to find some numbers for you. But in the mean time here are some things to consider about the power gains that trickflow got using their heads
1 compression is raised with 38cc chambers
2 they used their own TFS intake instead of the stock or even PI intake.
3 TFS Cams were used...not sure which ones though.

Not to say that the heads aren't a great design over Ford factory heads
Buy for the price they're asking it just isn't worth it for me when I already have a set of NPI heads to test on.

Also along those lines...consider NPI vs PI setup. The PI setup puts out more power...with the help of a redesigned, better flowing intake manifold and different cams. It just makes me wonder how much of the power is really coming from the design of the head itself.

Just my thoughts. Any input is welcome.
I understand that you are on a budget and you are doing this swap with what you already have.And what I have just read is that you can get NPI heads to flow near what stck PI heads so I don't know if it would be really worth it to get them ported.And the intake is only one thing in power.The heads themselves are where the real power is.

If you are on a budget and most of the time that is the case than yeah stick with what you got.And if you just want to see what the NPI heads can just do than I get what you are getting at.Just curiosity.And that is cool.But since you do plan on building a stroker motor I would say find some PI heads so you are not just starving the engine of better flow.

Here are two articles that have some info.There is another one but I can't find it right now.
http://www.mustang50magazine.com/techarticles/17518_96_98_two_valve_engine_upgrades/index.html

http://www.mustang50magazine.com/te...ing_stock_two_valve_cylinder_heads/index.html



I will admit that there is some interest to what the NPI heads will do with a stroker build.
 
It's mainly curiosity at this point. Brian just wants to see what numbers he can get from a NPI head. They're doing the porting right there at the shop and he has a flow bench in house.
In other news, I got a good deal on a PI intake on eBay last night. 145.00 with shipping.

Off the top of your head.....
If you take a stripped down NPI and a PI head and set them next to each other...what's the differences in the two?
 
I know the port shapes are different. The PI intake manifold is not an exact match to the NPI heads but some port-matching work can be done. Some people just used RTV.

I never looked at my NPI heads much but saw the PI heads through and through while I was putting my aluminum engine together for my Mustang.

I think this is the only pic I have from when I was replacing the valve springs. I believe you're more lift-limited on cams with NPI heads than PIs based on the profiles of the aftermarket offerings for each.
heads_cams.jpg
 
Thanks for the info!
I have heard that about the PI intake and NPI heads. that shouldn't be a huge problem.
The cams will most likely be custom ground no mater what head I end up using so that won't be an issue.
What setup did you build for your mustang?
 
Aviator short block (aluminum 4.6 w/ shallow dish pistons for 32v heads... ~ 90 lb lighter than iron IIRC), stock PI heads, PI intake, VT Stage II cams, Comp Cams valve springs, Thunderbird timing cover (to match the aluminum block & PI heads combo), Cobra oil pan/pump/pickup tube and windage tray, Hooker LT headers (never doing slip-fit again or LTs on an SN95/NE with stock K-member again!), matching X, Dynomax Super Turbos and stock pipes.

It put down 302 RWHP but pinged on stock timing w/ 93-octane gas so my tuner backed off 3 degerees. It still moved but I wanted more so I threw on a Snow Performance Water/Meth injection kit and had it advanced 2 degrees past stock before I sold it and it still wasn't pinging. I tried 2 heat range colder plugs and they helped a little but my baby was an alcoholic.

Here's a pic of it assembled. I call it "MILF":
MILF.jpg


And the dyno sheet. I realize it's not SAE corrected and the temp for the earlier run is screwy. Lower numbers are -3 degrees timing:
Dyno.jpg
 
How the hell are you going to stuff those headers down inside the LS?

What about the ground clearance on that oil pan?
 
Yeah I wouldn't even try that isht in a Mustang without a tubular k-member again! 2 of the primaries on the driver's side wrapped around the steering shaft, requiring the slip-fit horror that had me smelling like a weedwacker every time I exited the car. I suppose I could've had them welded.
 
Yeah I wouldn't even try that isht in a Mustang without a tubular k-member again! 2 of the primaries on the driver's side wrapped around the steering shaft, requiring the slip-fit horror that had me smelling like a weedwacker every time I exited the car. I suppose I could've had them welded.
meh, it's not bad. just dropped a dohc from a mark into my 04 v6. Engine/trans/longtubes all in one shot.

OP, sounds good. I'm in indy also. Can't wait to see finished product. You're putting a mustang engine in your lincoln and im putting a lincoln engine in my mustang....
 
8.8 swap brackets are welded in for the rear end. The front sub-frame mount bushings were starting to crack and they aren't replaceable. Only way is to purchase entire sub-frame from Ford. So they are going to cap them off instead and weld solid mounts in place. I'll get pictures as soon as I can. My computer decided it has had enough and I can't load pics from my Evo.
Also, my rear tie rod bushings are shot so they're going to fab tie rods with heim joints instead of paying prices for new.
Sway bar bushings will be replaced as well.
 
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Cool project. What trans you using....sorry if I missed it.

Just an auto trans from a 99 crown vic P71. It's getting built to handle the power though. There's quite a story where the engine and trans came from.
originally it was all from a 99 p71. My friend's 99 f150 had some head problems so we exchanged long blocks since i'm going to be replacing everything anyway.
So the block and heads are from a 99 f150 and the trans from a 99 P71
It's all apples to apples though :)
 
Just an auto trans from a 99 crown vic P71. It's getting built to handle the power though. There's quite a story where the engine and trans came from.
originally it was all from a 99 p71. My friend's 99 f150 had some head problems so we exchanged long blocks since i'm going to be replacing everything anyway.
So the block and heads are from a 99 f150 and the trans from a 99 P71
It's all apples to apples though :)

IIRC '99 heads might be a little short on spark plug threads (Lightnings had a habit of blowing them right out of the heads). You should be fine N/A but if you ever throw boost at it you may want to get some inserts first.

meh, it's not bad. just dropped a dohc from a mark into my 04 v6. Engine/trans/longtubes all in one shot.
I have large hands and (now scarred) fingers. It was not fun for me. I'd just do a tubular K next time. Much lighter and easier to drop it or swap suspension components.
 
not much new to report on yet. I dropped off the gears on friday hello there going to install the gear set today. and also work on welding the solid mounts that are replacing the rubber bushings on the subframe.
 
What the story on the driveshaft, does it need to be lengthened or shortened?
 
Is the 4.6 that much taller that it won't fit under the hood? I want to have a custom hood done eventually so if it doesn't fit I guess that will be the time to do it.
Or I could just run without a hood. (little joke there)
I should be well over 400 to the wheels with this build. I would love to See 450 N/A but only time will tell.



Please don't take this the wrong way but it is a REAL tall order to think you are going to hit 400-450rwhp on a SOHC 4.6, especially on the PI intake manifold. Most people that fully build their SOHC 4.6's for N/A hit maybe 350-360rwhp give or take. Some a bit more but it is RARE. 400-450rwhp is built DOHC 4.6 territory, not SOHC. Not meaning to rain on your parade but I have been in the Mustang scene for a while and built my fair share of 4.6's for N/A, DP Nitrous, and blown applications. I wish you the best of luck but don't be too surprised if you dyno quite a bit lower than your expectations once you get the car on the rollers. Cool project by the way!
 
He must like the look of S H I T in the engine compartment.:)

KS

LS1,2,3,6,7,L76 and L92's are some real badass engines. Mod em for huge power while N/A and simply phenomenal power when blown. But I do agree that Ford engines should go in Ford vehicles and GM engines in GM vehicles though. :cool:
 

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