'88 T-Bird 4.6 DOHC swap.

Topic: '88 T-Bird 4.6 DOHC swap. (Read 19583 times) previous topic - next topic

'88 T-Bird 4.6 DOHC swap.

March 14, 2015, 07:54:24 AM

Hi folks, I'm hardly the first person in here to talk about this, but I'm rather keep to try shoving a 4.6 DOHC under the bonnet of my 1988 Thunderbird. It currently has the 3.8 V6 and I'd love to try something new in there. It's hard finding info on just what I'd have to do, what mods I'd have to make to the brakes and front suspension etc, so I'd like to get some info and be pointed int eh right direction. Has anyone successfully done this? I'd appreciate any info on this. Thanks guys, James.

'88 T-Bird 4.6 DOHC swap.

Reply #1 – March 14, 2015, 09:36:45 AM

As far as I know there are 3 here currently doing the swap.

http://www.foxtbirdcougarforums.com/showthread.php?33763-My-85-TBird

http://www.foxtbirdcougarforums.com/showthread.php?32630-T-Bird-Resto-Mod-UPDATE-5-9-14&highlight=

http://www.foxtbirdcougarforums.com/showthread.php?18403-88-Cougar-XR7-4-6L-3V-update-12-27-2011-Engine-trans-and-TC-rear-end-in

'88 T-Bird 4.6 DOHC swap.

Reply #2 – March 15, 2015, 09:41:34 PM

The 4.6 4V is 300-320hp stock. You can build a 350hp 5.0 HO for less to around what it would cost to swap a 4.6 4V into your car. The only 4.6 4V I would swap in would be an 03-04 Cobra engine. If you're going na and want a DOHC engine there is really only one choice: 5.0 Coyote. Blows the 4.6 4V out of the water na or supercharged.

'88 T-Bird 4.6 DOHC swap.

Reply #3 – March 15, 2015, 11:41:12 PM

Id do a carbed one if it was me. I have no want for a obd2 system.

'88 T-Bird 4.6 DOHC swap.

Reply #4 – March 16, 2015, 12:58:35 AM

Given that he's in California, I'd say that a carb is about as likely to appear under his "bonnet" as an intelligent person at a justin beaver show...or any other artist of such ilk, including but not limited to kanya, florida georgia line, or any such pseudo-pop/top 40 shiznit. :D

Just like buying a car...look past the gloss, the shine, and gee, whiz! doodads, and find the shiznit that really revs your engine. My sincere apologies if bieber, kanye, or the like...really rev your engine. There is no hope.

Back to topic. If I were going to swap in a 4.6, I'd either do a DOHC swap, ala Termi Cobra, or at least something like a Mark VII, etc.

But why limit yourself...go for a Navi 5.4 mill......

'88 T-Bird 4.6 DOHC swap.

Reply #5 – March 16, 2015, 04:59:02 AM

I'm not looking for huge power, but a Mark VIII was actually what I was thinking. They're not too expensive on E-bay, though Modesto isn't exactly the best place to find local junk yards, plus I don't have a pickup truck or other suitably large cargo type transport vehicle. And good job on spotting my usage of the Queen's English, I'm an Aussie transplant. I figured the Mark VIII engine would be a decent bet, I'm just nervous of what I'd have to do to the fuel system, brake and front suspension. Then there's the drive shaft, transmission. Gives me the horrors. Honestly if I had my druthers I'd put in a 3.7 Duratec V6 with the matching 6-speed transmission which goes with it, but I'm not made of money. Shame, I'd like 305 HP with 35 MPG highway.

'88 T-Bird 4.6 DOHC swap.

Reply #6 – March 16, 2015, 12:50:09 PM

Quote from: thunderjet302;446114

The 4.6 4V is 300-320hp stock. You can build a 350hp 5.0 HO for less to around what it would cost to swap a 4.6 4V into your car. The only 4.6 4V I would swap in would be an 03-04 Cobra engine. If you're going na and want a DOHC engine there is really only one choice: 5.0 Coyote. Blows the 4.6 4V out of the water na or supercharged.

Actually the MK VIII are 280Hp @ 5750 RPM, Torque is 285Ft Lb @ 4500 RPM...

The '93 & '94 use OBD-I...

'88 T-Bird 4.6 DOHC swap.

Reply #7 – March 16, 2015, 04:20:13 PM

Quote from: TurboCoupe50;446171

Actually the MK VIII are 280Hp @ 5750 RPM, Torque is 285Ft Lb @ 4500 RPM...

The '93 & '94 use OBD-I...

True. I was thinking of the 96-01 Cobra and 03-04 Mach 1 4.6 DOHC

Either way I'd rather have a 5.0 Coyote instead.

'88 T-Bird 4.6 DOHC swap.

Reply #8 – March 16, 2015, 08:05:21 PM

If you are concerned with a budget build then stick to the 302W family. Its been done so many times and parts are cheap. I'm with thunderjet302 on the 5.0 Coyote motor, if I was going to do a modular motor it would be that one. Now where is my lottery ticket....

Darren

'88 T-Bird 4.6 DOHC swap.

Reply #9 – March 21, 2015, 05:50:47 PM

My worthless two cents..
IF cost is the concern, stay with a good 5.0. Second, why waste your time with a "small" (cid that is) Coyote or DOHC engine, I would (am) installing a stroker Boss 429 engine in mine. Just me..

'88 T-Bird 4.6 DOHC swap.

Reply #10 – March 21, 2015, 06:12:40 PM

Quote from: crossboss;446417

My worthless two cents..
IF cost is the concern, stay with a good 5.0. Second, why waste your time with a "small" (cid that is) Coyote or DOHC engine, I would (am) installing a stroker Boss 429 engine in mine. Just me..

Well, not everyone has 10,000 dollars to build a stroked Boss '9.

If I did, I'd have a force-fed 427w, but definitely something from the "small block" Windsor....why lug around the penalty of 250-300 pounds of extra weight? Sure, sure...Boss 514 sounds intimidating as hell, and it'd would be fast, and it would cost a hell of a lot more. Especially if you had to start from scratch and get block and heads, too. You can still find a 5.0 or a 351 in nearly anyone's backyard, a 429, not so much, and likely not a Boss block at all. Of course, a windsor based block in which to make a 427" combo is also going to be aftermarket, but still, it's cheaper than a 385 series block.

Any pics of your build? I DO like looking at big block foxes, and am weighing on putting a 460 into my '84 notch.

'88 T-Bird 4.6 DOHC swap.

Reply #11 – March 21, 2015, 09:04:09 PM

I guess I should be more detailed in my answer. Yes, a W based engine is cheaper, more common and best bang for the buck. As for building a Boss Nine engine compared to a Coyote or 4.6 DOHC its about the same. What I mean about the same is by using the garden variety 429-460 block with Kasse heads. Coyote engines (new) are around 10-12K, used maybe around 5-6K. So, if you equate the cubic inch, and horsepower difference, you're way ahead with the Boss 429. Natural aspired Boss Nine engines are common in the 700-900 HP range. NO Coyote or 4.6 DOHC is even close. Ok, yes, I am old school. As for photos its still all a matter of building/acquiring parts at this stage, so no pics at the moment. I will keep everyone abreast of the project.

'88 T-Bird 4.6 DOHC swap.

Reply #12 – March 21, 2015, 09:49:56 PM

Well....a better coyote makes somewhere around 400 horsepower. Short of a honest to god '69 or '70 Boss, NO stock 429/460 made those power numbers.

And of course, throw twins and a tune on even a stock Coyote, and you'll see a grand's worth of horses. Don't forget the GT500 KR had close to 700, with plenty more left in the stable.

I love the Boss 429, epsecially a '70...hands down, my ultimate dream car, BUT....

if I had to pick one, and I could never have another Mustang for the rest of my days, well, I'd probably pick the 2013 Boss 302. It turns, it burns, it's fast, aero, and looks good. make mine Grabber Blue, and thank you!

The Boss 429 is just too finicky for me..I'd want to drive it every day, and likely the frequent attention to the exotic Ford hemi killer would soon wear me down on it.

'88 T-Bird 4.6 DOHC swap.

Reply #13 – March 21, 2015, 11:10:48 PM

No argument on your statement, as an old 69-70 vintage Boss 429 IS finicky. However, I am referring to a modern Kasse Boss Nine engine. Now, IF you want to compare apples to apples the Boss still wins. Natural aspired to natural aspired, it still goes to the Boss. Ok, lets add the power adders as you mentioned, still hands down to the Boss. The only reason the Coyote and 4.6 are in more demand today is they made more of them, are most likely to be in a certain class of racing, and are more available to the average guy. Don't get me wrong, I love all muscle cars, old and new, Fox bodies and older Mustangs (esp 1969 Fastbacks). So, I do get your point. As for me I am doing something other than the norm. Just me..

'88 T-Bird 4.6 DOHC swap.

Reply #14 – March 22, 2015, 05:47:08 AM

I like the DOHC because it gets pretty good power, and I'm a real nerd for DOHC efficiency. Plus naturally aspirated, that engine in that size car would likely get good mileage. I'm hoping better than what the V6 gets at around 25 MPG. Also I'm kind of afraid of the costs and complications with doing ports etc with the 5.0 Windsor, especially if it'll kill my MPGs. If I had the money and resources I'd put in the Duratec 3.7 V6 with the Mustang 6-speed tranny. 305 HP and 31 MPG rather impresses me. Anyway I'd like to at least look at a couple comprehensive write ups for swapping the Mark VIII motor, just to see what I'd need to do as far as the suspension and fuel system and mounting brackets etc. Google just hasn't been so kind. Found a video from a guy who did the swap in his '97, but no details or schematics etc. Even if I eventually decide to abandon the project and just fix the current engine and rebuild the transmission, I really want to at least get the info. I was thinking stick in the axles from a Turbo Coupe and interior from a 5.0 with a floor shifter. Otherwise sticking in a 5.0, especially going simple with stock would give me nearly identical power to the V6 but leaden the handling with the extra weight and probably lose some MPGs.