i have a dodge ram 1984 d150 3.7l slant 6 with a three on the tree highway greared trans and im trying to figure out the best way to put more power to the engine without obliterating my mpg any ideas?
Short of some elaborate, modern solutions…I was under the impression that “more power” always means less MPG. Especially with a 1984 Dodge.
But I could be wrong.
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thats ok but im looking for just a little boost is there a turbo or anything i can put into it to give it a little extra kick?
You should ask a Dodge forum. There are plenty of them on the internet.
the only issue ive ran into is i dont have a credit cardand the ones ive been to already need a credit card
thx for the web page
Did you fix your shifting problem yet?
More power takes more fuel. Always.
You have an engine that has not been made for 30 years that wasn’t known for its power even then. So there are no bolt-on performance parts.
The only thing I can suggest is to change the rear axle ratio to about a 4.10:1 ratio and swap the transmission to a 5 speed with overdrive. That will take some fabrication and a custom drive shaft. It will make the truck peppier without wrecking the fuel economy. The cost will be about $3500 give or take depending on how much fabrication is required.
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Modern engines that are turbocharged are built with stronger connecting rods and “beefier” bearings.
Are you prepared to tear-down the engine in order to install new rods and bearings?
Also, you would need to reduce the normal compression of the engine in order to use a turbocharger.
Are you prepared to do that also?
You can probably find a turbocharger that will fit your engine, but using it in “boost” mode is a sure way to kill your 34 year old engine.
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Agree with that.
I had an 82 Ramcharger it came stock with 3.2:1 gears, lacked power and gas mileage was about 11 mpg
Changed gearing to 4.10:1 and had a lot more power and gas mileage actually went up to 13 mpg, no longer lugging the engine on the interstate doing 60 mph
This has the 225 slant six, right? There are a few things you can do to get a moderate power bump. Clifford Performance is the place for 6 cylinder mods:
https://www.shop.cliffordperformance.net
RE credit card. Get a prepaid, reloadable card.
Everything else depends on how much you are willing to spend. The lower gear ratio (higher number) rear end would be the first, probably most economical, step. Any future modifications would benefit from the rear end change in as much as modifications, with the possible exclusion of a super charger or turbocharger, tend push your power band into a higher RPM range.
ok so if i do the welding myself and just buy the parts how much will it be like an estamate
does this hold true for a 2008 poniac g6 v6?
From g6ownnersclub.com
Since you have the GT, that means you have the V6 engine. There is no room under the hood to mount a supercharger. A turbo might be possible but it would be very tight. You would have to clear up a lot of room (reloacting the battery and other things for example) and do tons of custom plumbing under the hood. One other possibility is a rear-mounted turbo, but again it’s complicated plumbing.
One guy did the work on his then-girlfriend’s 6 but it has the 4-cylinder engine which has more room under the hood (but not much). The turbo was working in that it made boost and such but he could never get the car’s computer to work with it properly and then things happened and the project stopped. At that point they were over $5000 into the project and still hadn’t upgraded the suspension or transmission…
So yeah, if you have a lot of money, time, and especially expertise to throw into the project you could try to come up with your own turbo system, but there’s nothing made to fit our cars; it has to be fully customized. Most people on starting to research this realize that it’s way cheaper to sell their 6 and take that money plus the turbo money and buy something faster. Like a G8 GXP. 
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$350 for the gears and installation parts… no welding needed. Special tools are. A press and dial gauge, and calipers, 1/4 drive inch lb torque wrench and scrap steel for holding tools.
$800 at least for a used transmission with the integral shifter, misc metal for the crossmember, welding. A driveshaft shop would charge $200 or so to shorten and mod the driveshaft. The unknown is any mods needed to mate the trans to the bellhousing. The speedo drive cable will need some mods, not sure of the cost. I think I’m at about $1500 with misc costs tossed in.
The bigger issue is if you have the ability to find and pick the right parts and actually do the swap.
He updated on the other thread. He does not have a 3 speed MT, but an automatic.
Peter:
Does this slant-6 still have a carburetor, and still have a distributor that you can rotate to modify the ignition timing? If you’re not worried about emissions, you could get more power by:
- advancing the ignition timing by a small amount. 2 degrees should be safe. Occasionally you could advance it more, like 3-5 degrees without incurring detonation. If you don’t mind using a higher octane fuel, you could advance farther.
- increasing the diameter on the main jet of the carburetor by a couple of thousands of an inch. For example, if the current diameter, which is stamped on the jet, is 0.050", you could find a 0.052" drill and very carefully increase the opening of the jet.
You’ll likely need to remove or gut your catalytic converter.
You’ll be surprised at the added pep, and like all the cars I modified back then, you’ll get 1-3 more miles per gallon. If you drill the carb jets out an additional 1-2 thousands of an inch, power will continue to increase, but your gas mileage will decrease. Increase the opening further (beyond the 116% of stoichiometric ratio for cars of that era) leads to a decrease in both power and mpg.
But do understand you are tampering with emissions. Most states waive emissions testing for vehicles over 25 years old. I do not know about your state. You need to decide if these mods are for you.
i have a carb and absolutely no caddy