Posted By: 360D100
1984 Dodge D100 questions - 02/14/15 06:48 AM
Hello everyone! Have some questions for. I have a 1984 Dodge D100 with a 318 and a 833 overdrive tranny. Its a short bed. I am wanting to make more power with the 318. Its bone stock. Except for the ignition has been converted over to a stock electronic ignition. My plan is to put magnum exhaust manifolds on it off of a 5.2 and then have a dual exhaust installed. Sunday I am going to look at a Edelbrock LD4b intake. The only thing is the guy said that the intake has been gasket matched and now has bigger ports than a 318. Said it was on a 340. Will that matter? I know that this intake was originally for a 318 correct? I may add a cam down the road. I may add a 360 way down the road, a 89 Dakota is my main project right now. Just wanting to wake the 318 up! Does this sound like a good plan? Right now the truck has a 8.25 rear with 2.94 gears non suregrip. The guy with the intake says he has a 9.25 out of a 89 Dodge truck that has a suregrip and 3.55 gears. Said it would be a easy install. I have never done that before. Only familiar with 8 3/4 rears. I also found a suregrip unit- I think it is, for the 8.25 rear. It is a 27 spline. I will try to post a couple of pictures and let me know if it is. If it is, I could just buy the gears that I want and have it all installed correct?
Posted By: moparmandjh
Re: 1984 Dodge D100 questions - 02/14/15 11:01 AM
I think an Air Gap intake would serve you much better.
Posted By: 360D100
Re: 1984 Dodge D100 questions - 02/14/15 11:29 AM
The Air Gap would be better than the LD4B?
Posted By: 360D100
Re: 1984 Dodge D100 questions - 02/14/15 12:11 PM
If that is a suregrip for a 8.25 is that the right one where I could use lower gears like say a 3.55 etc.?
Posted By: DaytonaTurbo
Re: 1984 Dodge D100 questions - 02/14/15 06:40 PM
Leave the 318 alone for now. I would swap in the 9.25 rear. If it was working, it would be an easy swap (and likely cheaper) than buying a 8.25, plus it will hold more power than the 8.25. The gears will help out your 318 off the the line.
rpm air-gap is a little to much intake on a stock 318
the LD4B is the best intake for a 318. if has been ported to the 340 size opening. just use a fiber 340/360 gasket felpro 1213
that intake wakes a stock 318 up real nice. I used a 660 eddy carb on mine.
it also worked great on the 360 headed 318 police engine I have.
watch the truck axle/carrier/c-clip/wheel bolt pattern change in 85 when sorcing parts to rebuild the 8 1/4 9 1/4 truck axles.
watch the magnum manifolds IIRC the dump right on the starter and do not fit the d series truck chassis due to shifter linkage/starter
use a set of long tube hedmans
79080 for 2x truck and 79170 for a 4x4 or 2x truck chassis
79250 for BB truck chassis
Posted By: Golden-Arm
Re: 1984 Dodge D100 questions - 02/14/15 11:22 PM
like scratch said, the ld4b is great for the 318. get a good carb, and i'd just get some headers and run the duals. if the 9.25 was in a truck, it should bolt right in. those 3:55's will wake up the truck nicely. if you keep your rear, look at a 3:91 for your 8.25 and a suregrip. trucks are light enough in the rear, to not worry about hard hook-ups, and breaking stuff. (unless you load the bed down, and run some wide slicks.) if you're really feeling adventurous, a 1968 340 stick cam will make the 318 wail, along with the other things from above.
Posted By: 360D100
Re: 1984 Dodge D100 questions - 02/19/15 12:29 AM
Will I found out that the suregrip unit that I posted would not work. What would be the easiest and cheapest way to get a suregrip in my truck? I cant find anything local as far as complete rears. Although I did find a rear out of a 95 Dakota 8.25 rear with a 3.55 suregrip. Would that work, the insides? It has 3.55 gears. I would like to find a complete rear that I could just bolt in. But not having any luck. If I get a suregrip and some gears I will have to have a shop swap that and set it up. Any help would be greatly appreciated.
Posted By: poorboy
Re: 1984 Dodge D100 questions - 02/19/15 04:29 AM
A 95 (91 and newer) Dakota rear end will have 6 bolt wheel flanges. It will probably bolt into your truck, but you will need the rear 6 bolt wheels.
Unless you stick with the same era (82-93 full size truck) Dodge truck rear end, your wheel bolt pattern will likely be different then what you have now, be sure to get wheels to match the bolt pattern for the rear axle you end up with. Gene
Posted By: lunacy
Re: 1984 Dodge D100 questions - 02/19/15 03:00 PM
I have a b-body axle housing and axles that will eventually get swapped under my 73 so I can run some 15x10 slots (3.5" back spacing). If my measurements are right it will narrow it just enough to get them to tuck up in the fender, and i'm hoping the center sections will swap right over.
Posted By: dogdays
Re: 1984 Dodge D100 questions - 02/19/15 07:06 PM
The 9.25 with the 3.55s and Suregrip is the easiest. By this I mean unbolt your current rear axle, bolt in the new axle. The driveshaft length will be the same, the 8.25 and 9.25 were the same distance between axle centerline and U-joint.
There's no reason to even smell gear oil on this swap. It's just remove and replace. Well, you will have to bleed the rear brakes, but nothing more complicated than that.
As for the intake, you have many choices. The LD4b is good, the LD340 or RPM Air Gap would be good, the Performer would be good, even the stock cast iron spreadbore intake that was used on 360s is good, if heavy.
Get a carb that matches the flange on the intake. I have had middling results with square to spread adapters.
Don't worry about the port mismatch, at this power level it has no effect. Just use a gasket that will seal whichever larger holes you have. I guess that'd be a 360 gasket.
Even with the wimpy 318 cam the 4 barrel and dual exhaust will help a lot, even better with 3.55s.
Keep it simple and you'll have success.
R.