please correct me if I'm out to lunch.....but most of the post on building the 302 will work but the end result still does not solve the owners problem of frequent downshifts, in fact the mods will likely increase the occurence b/c most of those builds will raise the effective TQ band...you will have a stronger engine but at a higher RPM, which is not necessarily better in a truck, what you want to pull stuff and turn large tires w/o a lot of shifting is low end TQ

 

almost forgot...the gear swap will work as well, but with resulting crappier mpg...from what I hear 302 & 351 give you approx the same mileage.........your choice....I love my 289/302's but IMO they belong in a mustang (or maybe a ranger)

 

Yes.. but there's nothing you can do to the E4OD to prevent it from downshifting when you lean on the throttle, so you might as well work with it and add gears and more engine power. More gearing will help the downshift problem because the motor will operate in a range where it produces more TQ, so it won't loose as much speed on grades. A bigger engine will just drink more fuel in this case unless a tranny controller of some type is added to change the shifting parameters. But all the plug-in modules I have seen for these trucks raise the tranny shift points to higher rpms, and that's not what is needed here.

 

Paul,
I realized where you got the rpm numbers now. Fortunately/Unfortunately I have the AOD tranny not the E40D. I know that in the calculator you linked me to, there was a difference in the final rpms. At 70mph it shows my rpms at 1755. I'm sure this will make a difference in this whole process.

I'm a little torn, and part of me wants to see what I can really make this 5.0 capable of. Sounds like gearing is still the first thing I need to do. I think I agree with vols that since I don't plan on doing serious offroading that the 4.10's should be good and still provide better mileage. After that I guess I'm into rebuilding the engine with cam and MAF conversion. I do have shorty headers that I plan to put on, but they are from a Mustang, and the outlet is in the wrong place to bolt right up.

Another question came to mind. My father had an 85 Mustang GT convertible with a single port fuel injection. Would going back to something like that offer a difference that is workable from the S/D? Just a thought. Any opinions?

Thanks for all the input. It has been very enlightening!

Rick

 

The AOD is 0.67 and the E4OD it's 0.71... Won't make much difference to HWY engine speed, though it does shift rpms down even further which is bad. This does make a difference to the shifting issue I was going on about earlier though, the AOD takes a lot more throttle input before it drops out of OD, so you can take advantage of increased engine TQ more than you could with the electronic trannys. Shorty headers won't help here, but longtubes do so sell those mustang headers and upgrade. You'd have to modify the Y pipe to fit the mustang headers so you may as well put that work into something that also boosts TQ. I put longtubes on my stock '89 5.0 truck and the TQ improvement was impressive.
If you want to try a mustang intake you'll need the HO version, in general the long runners of these EFI intakes boosts low rpm TQ production. The truck intake uses very long runnes but they are also larger volume than those on the car, so air velocity at low rpms is lower and as a result it doesn't make as much low rpm TQ as the car motor. With a 1" spacer between the upper and lower, I think the HO intake would be an improvement over the truck intake.

 

You must be taking a long lunch then ssidney.....and apparently you've never dirven a 302 powered later model truck before....my truck doesn't hit an optimal power band till about 3200 rpm...now my redline is 5200 that's more than half of what i got available to get her up to power......basically you're telling him to drop in a bigger motor which does get NEAR the same mileage as the one he already has because well, no replacement for displacement......horsepower is not what get's things rolling...if it was then a 300-6 would be a waste of quality metals now wouldn't it?It's the torque.....and if a budget doesn't fit to have another engine dropped in...especially one that's "gold" and hard to find in a certain area, then there's no reason to dish out that kinda of dough.You can get more torque and better pulling/rotating power other ways...whether it be lower gearing, an underdrive pulley set, exhaust modifications or intake mods....there are ways to do it for less than it would be for an engine that you really have any idea what the condition is...at least with his present motor he knows the operating condition.The one inch spacer is a very good idea and can be had for under 75 usually...also note that if you get a Mustang HO intake you can do a 180 to have the intake come out like on a Gen 1 Lightning........Good Luck

JR

 

funny you should say that...you've just proved my point, the 302 DOESN'T become effective until you hit higher rpm, so in that case you will be changing gears AND building the engine...as for the 300-6 that's a whole different story, you cannot compare the low-end TQ of a long stroke inline to a short stroke small-block, especially a 302 which has one of the best bxs ratios of any v8...unless you go back to the 289. FYI I have driven most and combination of Fords running gear except the newer ones, and unless I was building a blvd cruiser, which'l never happen...I'll stick with the mpg, reliability, cost effectiveness and power (I work my trucks) of the 351....as for the 300-6 my '68 merc L6 was slower the my '72 with a 302....until it was loaded.

 

That may be how you see my previous post but you completely missed my point...My point is the answer is not always a bigger engine...with a little work you can get more than enough power to pull the things you need to and usually on a better budget.

JR

 

I have another question along this thought process. As has been recommended, I found a 5.8L that someone has for sale for 300. It came out of a 90 E150 Conversion. He stated that it is ready to drop in and doesn't need a rebuild (I wonder if I should anyway). Well, the engine swap would put off my gear ratio swaps.

I'd like opinions on which way I should go now. Should the 5.8 be strong enough with the lower-end torque that it will be driveable with the 3.73s now or would the 4.56s be the better way to go at the moment, and why? I love all the input and you guys all give me so much to think about and consider.

Thanks
Rick

 

well....there ya go, that 5.8 should have plenty of b@lls for your gears and, if you choose, with the money you save by not changing gears you could rebuild the 351, upping the comp. just a tad and adding a bit of a cam....shouldn't change the over-all fuel economy much (could even get better) and you'll be impressed with the results ,

 

But will I still have the same problem of downshifting out of OD at the slightest input of throttle? Or will the torque range and torque difference be enough to overcome that?
Thx

 

should be enough

 

In the meantime use the calculater to find out what speed you are actually driving. With the bigger tires you are going faster than your speedo says if you haven't corrected it. Make a note of 65~70mph and what your rpms should be. Drive at those corrected rpms and it should be easier to stay at that speed w/o the tranny down shifting so often. More than likely your driving closer to 80 than 65 and really pushing the truck with those tires. I'm guessing here.

According to the calc mentioned above I punched in some numbers.

With the stock 235/75R15 approx 29" tires at 65 you should be turning 1966 rpms.
With 36" tires you now should drive at 1584 rpms to be driving 65

29" tires at 70 is 2118 rpms and 36" tires at 70 is now 1706 rpms.

You can see that you would be staying closer to the trucks powerband. Not a final solution but it'll help.

 

I already got the speedo calibrated for the tires so they are correct. I'm just hoping that with the 351 the increased lower end torque will minimize the downshifting at highway speeds. I'll probably get the motor in a couple weeks when I have some IRS money to spend. Christmas all over again!!! LOL

 

Ahh Ok, Ya my IRS money will pay off my credit card from last years upgrades.