Hey everyone, i am a newbie to ford engines and am doing a motor swap in mt Jeep, which is going to be more ford than jeep by the time i am done with everything.

Its a 91 YJ and so far i have a ford 8.8 with disk brakes and 4:10 from a 97 explorer to be installed, front diff will be replaced with a cut down HP 44.

The engine i am going to put in is this:built 400m/bored .030 and 268 comp cam edlbrock intake with holley carb(ill find out what cfm) and long tube headers, tranny is a built c-6 bb with pro street kit, the t-case is a np205(mated).. apaprently the previous owner dumped $5k CDN in the motor.

What kind of power will this put out 300hp and 400 tq? also i was rading through the thread about EFI conversion and looks like i might be able to work somehting out.



cheers

 

Welcome to the forum! It seems we have some things in common, like fords and jeeps.

First let me say try not to call it a 400M. Some guys on this forum are VERY sensitive about it. I have been verbally chastised for using that term myself. It will distract from getting answers to your questions by the guys who insist on being technically correct. *sigh*

Moving on, your overall engine plan sounds very solid. If the carb is anything but a Holley truck avenger, lose it quick. I had a holley street carb on my bronco and it was a nightmare. I would recommend the holley TA, the edelbrock, or even a quadrajet. Blasphemy to the pure ford guys, but an excellent off-road carb. I also want FI for my project, but I don't think I can make it happen because of smog laws. There is a very good thread on this forum about FI on a 400 (not 400M.) ha ha

The C6 will be a problem in something the size of a jeep. We have a 1990 yj ourselves, and I can tell you that any lift or longer engine / tranny combo will make driveline angles a huge problem. The C6 is an awesome tranny, just not so good in a jeep. You may need to contact advance adapters to find a solution to that.

You may also look into myjeeprocks.com. Many excellent jeep specific forums there. I don't think anyone on that forum has a 400 in their jeep, yours will be truly unique!

The 8.8 from an exploder is almost a perfect match for a jeep. That website has links and info from guys who have already done it. We are going to swap in an 8.8 into our jeep as well.

Good luck with your jeep, I am very curious to hear progress on your project!

 

BroncoChuck, thanks for the reply. Thanks for corecting me on the 400m vs 400.. at least i know now.

The Jeep already has 4" suspension lift and a 2" body lift, i will probably extend the wheelbase and relocate the fuel tank, the extra inches gained in wheelbase should help with the long driveline. i may ditch the c6 and get a np435, depends on what happens for what price.

The carb is an older holley not a truck avenger, so if i can't afford an EFI setup i will go that route. will post more info as it comes along.

 

Don't forget that any lift will further aggrevate your driveline angles. The NP435 or T18 are both shorter than the C6 and will hold up well behind the power of a 400. Not trying to talk you out of your choice of engine, but how did you come to choose the 400?

 

i found this combo(motor trans and t case) for $850 CDN from a guy in my area, lowermainland near vancouver BC. the previous owner spent alot of money on the parts rebuilding. it is cheaper for me to get this motor trans combo than to buy chev drivetrain but the 400 might not practicle for my setup.

 

That sounds like a great price on the combo! I crawled under the jeep and found some good news for you. The current drivetrain length from the front of the damper to the centerline of the output yoke is a whopping 76"!!! You should be able to come real close to that with the ford setup, maybe even beat it. Our rear driveshaft is only 13 1/2" in length and is not u-joint friendly. We have a 4" lift on our jeep just like yours.

Some things to consider: The 400 will need a lot more cooling than the 258. You will need to upgrade your cooling system to compensate. You may want to put an electric fan on the front of the radiator so you can find a coupla more inches by mounting the engine closer to the radiator.

Don't even think about using the stock rear axle. Put the 8.8 in at the same time or before you do the swap. The d35 is a fine axle in a jeep if you don't lift it, don't add lockers, don't go with bigger tires, or don't increase the power. Anyone of those will turn it into shrapnel quick.

Lose the Holley. If you plan on EVER taking this engine on any angle at all, the holley you have is the worst thing you can do to it.

If your current drivetrain is still intact, sell you jeep stuff to a jeep guy and build up your uber ford in a jeep package with the money.

Just for kicks, have you heard about the TMI stroker kit for the 400?