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Finally got a 4.2 shortblock. I'm at the point now where I am going to do everything while I have it tore apart, transmission and rear end included. As far as the engine, I was thinking of putting in forged pistons, and a cam. I was thinking about Morana for the pistons, and rpm mustang for the cam, but what does everyone think? Is Morana cheaper? I'll be putting my vortech on it, which turned out to be fine. Injector size, throttle body, and any thing else?
 

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This question was prolly been posed before, and you prolly have a great answer and please don't hate more for asking because I am really sincere about the question. Are you going to put a 4.2 in your MN12? What reasons do you have for the swap? It certainly is interesting.
 

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Nice choice of engines. I would go with forged 351W rods and Mikeal at RPM mustangs can help you order custom pistons to work with the 351W rods and 4.2L stroke, this would give you the backbone to support 11-12psi very reliable as the stock 4.2L crank is pretty tough. This is the route I'm going with my car in 2 years (next year the vortech gets put on) I'll be sticking with single port heads though as I have $$$ invested into them already!!! we are getting a few kick *** V6's in here now
 

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bigger displacement and more horsepower and deffinetely more torque. I too will be ordering a shortblock 4.2 next summer if not sooner and building it up with ported stuff. It would be awesome, JukeboxHero, if you made a tech article on it and took pictures of stuff and how your doing it. I think it would really help a lot of pople out around here...INCLUDING ME! which transmission are you going with? And which rear end?
-Thomas
 

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Yep, its a V6 that on the outside is IDENTICAL to our 3.8L's so all our accessories bolt up and our stock computers/wire harness work with them with just a chip. its a stroked 3.8L to be exact, same bore longer stroke.
 

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What is the difference between the normal upper intake manifold and the split port? Other than the big height difference. Is it just a less bent airway so it flows better? If there's not a big difference then I wouldn't think it's worth the money to get a new hood and all.
-Thomas
 

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You don't need a new hood, Thomas. The '99 3.8 mustang upper intake manifold is a direct swap with the truck upper intake intake-- UNLESS you want to use a distributor, which is what I did. The 3.8 mustang split-port upper intake should fit under the stock hood with no problems but it does not allow for the use of a distributor. If your car currently has a distributor and you want a stock hood with a split-port 3.8 intake, you will have to switch to DIS.

I got the hood long before I did the truck swap. I figured I already had the clearance, and I might as well have something under the cowl to justify its presence. Otherwise, at a glance, people would say "V6 T-Bird with a cowl. What a ricer!" I got the hood because it was cheaper than buying a stock one after a stupid accident.

The 4.2 is a very smart and practical swap choice for V6 MN12 owners-- I think I will write an article on this soon (I am moving to SoCal this week so it will be a while). Rancherlee, will you help me write the performance potential segment of the 4.2 article, since I have more experience strictly on the installation side? I think an 11 second V6 is possible considering Pete is running mid 12s (V6 Mustang) with a stock 4.2 longblock + Procharger).

Answering the question regarding the difference between split-port and single port intake, lets look at a few facts.

The '98 single port 3.8L engine makes about 145 hp in stock trim. The '99 split port engine is basically the same engine with the following differences: returnless fuel system, split-port upper and lower intakes, and split-port heads. The split port works like having a secondary intake manifold. The longer runners are optimized for low-end torque, while the short runners are there for upper RPM horsepower (these are closed by the IMRCs until a certain RPM-- I chose 3400 RPM). The '99 V6 mustang engine makes 190 hp-- a 45 hp improvement over the single port equivalent. Rancherlee, what are the torque numbers of a stock single-port 3.8L?

Some of the '99+ V6 Mustangs do NOT have IMRCs (Intake Manifold Runner Controls)... a feature which I consider CRUCIAL to anyone putting a split-port in a heavy car. I will address IMRCs on a later day... Unless someone wants to beat me to it.

This does NOT mean that there is no potential for single port engines. Rancherlee might have more accurate figures, but the single port head, with a good porting job, will out-flow the split-port head. Maybe the single port plus a built lower-end will yield better results with high-boost... but there is always the dreaded head gasket...

I'm happy to say that I have no regrets over this swap. I finally can beat some of those cars I was ashamed to lose to with my 3.8, such as Camaro RS's, '99 V6 Mustangs, and 2.3L Preludes. My times are better than many 4.6 V8 T-birds, and I have yet to do any serious exhaust work. One of the benefits of sticking with the Essex based engine is that all of the aftermarket SC exhaust products work. I am expecting to receive some sweet Kooks headers and Supercoupe performance downtubes this week. I know I can run 15s with this car as it is in either cooler weather or lower alts. I ran a 16.31 @ 85mph in Tucson AZ (2800 ft??) at 105 degrees. Once in CA, I think I will be in low 15s with the new exhaust.

I am looking forward to boost in the future, so my exhaust will be optimized for that. A good NA oriented exhaust on a 4.2 with tall gears will most likely put the V6s in high 14s. This is more than respectable.

These are very exciting times for V6 owners. V6 T-Birds are a dime a dosen. Insurance is reasonable and they offer all of the comfort of their V8 counterparts. On top of everything, the V6 is lighter. The only downfall is that our drivelines are inherently weaker. I will let you guys know when I break a half-shaft or my current differential.
 

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What are the 4.2L engines out of? I was interested in getting a 4.2L and seeing if my friends want to help me with that. My one friend has a 5.0 Mustang and was wanting to see if I could give him some competition.:D They're rebuilding 78 and 79 Ford pickups and figured they'd know some stuff on switching out engines. They said they'd help me if I had some mechanical questions.:p
 

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First off, for 93pimpin. The 4.2 engine are taken out of a 97 and up ford f-150 truck. It's still a v6, and is virtually identical to our engine with the single port installed on it. And for PJ-4.2L So it's basically the same idea of a SHO or VR6? like having shortened running and lengthened runners that swicth on and off at a certain rpm? That's sounds pretty fun. I always wanted to know how they switch, I guess having one would answer my question. I can't wait to get started on it in a year or so. Yes I agree with you, these are exciting times. When some newbie would say, "How do I put a lot of power into my 3.8?" the answer would be,"You can't." But now there is hope for people. And It's cheaper than swapping for a 4.6 or 5.0 because with these you get to keep all your accessories. Except in the case of the split port where you need a swicth from a distributor to a DIS as I understand it? So what is there to do about the half shaft? And which differential would you recommend? I'd still be using it as a highway and city driver. I was thinking 3.55. And I am also thinking about a swap to a 94-95 sc manual tranny. Has anyone ever swapped a sc man tranny in their 3.8 na? Well mine wouldn't be a 3.8 anymore, but the same idea.
-Thomas
 

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Also I have another question for you PJ, totally off the subject. How do you make your gauges glow blue like that? Sorry for going off the subject but I really wanna do that. I also had a second thought. Maybe in a few years they'll be having a 4.2 forum! Oh well. See ya.
-Thomas
 

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Thomas said:
First off, for 93pimpin. The 4.2 engine are taken out of a 97 and up ford f-150 truck. It's still a v6, and is virtually identical to our engine with the single port installed on it.
You mean single port, right? Also, an important note... If you are getting the short bloc out of a truck, GET '98 UP! The '97s (like mine) have a different girdle setup. It will not clear the 2001 V6 mustang oil pan which is necessary for the swap. I was lucky and came across some used parts to make it work-- very unlikely to happen again. You can not buy the appropriate parts new from Ford-- you'd have to buy the entire block assembly. Morale of the story-- stay away from '97 unless you enjoy delays and head-aches.

Thomas said:
And for PJ-4.2L So it's basically the same idea of a SHO or VR6? like having shortened running and lengthened runners that swicth on and off at a certain rpm?
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Except in the case of the split port where you need a swicth from a distributor to a DIS as I understand it?
-Thomas
Yes, the intake runners work alot like the SHO's runners. The different runners are selected by six butterflies (one in each short runner port of the lower intake), which are vacuum actuated with a pair of vacuum switches. This is called Intake Manifold Runner Control (IMRC). Since my EEC didn't have provisions for the IMRCs, I had to improvise with some MSD products and creative plumbing. I won't get into details since it will just needlessly clutter the board.

The only way to keep the distributor is by using the F-150 intake. But then you have to do someting about your hood.

About the halfshafts, V8 and SC halfshafts (SC are stronger) are a direct swap. Also, you can pick any gear ratio for your differential as long as it is in a 8.8 (our cars come with 7.5 inch differentials). The 8.8" are not hard to come by.

Personally, I would not do the SC tranny swap at the same time as the engine swap-- it only compounds complications. It can be done, but first I would see how it drives with your current tranny-- although the F-150 does NOT have provisions for the TV cable on AODs-- you'd have to do some adapting- can't be too hard. Using the SC tranny means new drive shaft, yadda-yadda...

PJ

About the gauges:
Click here.
 

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Thomas said:
Also I have another question for you PJ, totally off the subject. How do you make your gauges glow blue like that? -Thomas
Just realized I didn't answer your Q. Blue celluloid... I hear that blue stage lighting cells work well. Blue bulbs don't work.

PJ
 

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so what all do you need to buy for the swap? 98-?year engine, and what come's out?
 
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