Please help. i have been building a 93 dodge dakota 4x4 for years now and i still cant seem to get it to run clean. it is very inconsistent. sometimes it runs like i imagined it would when i started the project and other times it falls on it face and gets **** gas mileage. changes day to day start up to start up.

so the truck is like i said, a 93 dodge dakota 4x4, 3 inch lift on 31x12.5 super swampers, with 3.91 gears posi front and back. i kept the transfer-case and adapted a non electronic 91 ram 518a tranny with oil pressure converter locking. i took the v6 out and started to build a free 318 i got out of a friends rusting 74 dodge dart with 49,000 miles on it. i did a bottom to top rebuild. block was cleaned, rebuilt, and bored once over. a 7qrt. oil pan, cleaned the cast rods/balanced, new speed pro pistons, 2roller timing chain, cleaned and rebuilt the cast heads/slight polished ports and chambers. headers with a two 2 1/4" into one 3"exhaust at the muffler. Edelbrock performer dual plane no emission intake-manifold with matching cam, mopar ignition, and a 470 holley truck avenger carb on a 1 inch space adapter.

i have been trying to figure out why it has no power on the low end torque. this is all i want for my truck, low end. it has a hard time hill climbing, sputters and gags on acceleration sometimes, and no slow crawling/towing torque. i think it might be the fuel delivery (carb cfm or jetting?) gearing, or the compression 8.5 to 1. but why would it run great sometimes.

so if anyone has any suggestion on what else i could do, fix, or something i messed up on, or missing let me know. i would like all the input i can get. i really want a good truck with torque. Please and thank-you.
Mahalo & ALOHA

 

Well I hate to say it, but since this is a completely custom build, we may not be able to help you. The problem wouldn't be specific to to a 1st gen Dakota!

We may be able to help you with some more information about your build though. What cam went in the engine? I ask because if you put an agressive, high end cam in your engine, I'm not surprised it has no low end. Also, did you change over the high pressure EFI fuel system (40+ psi) to a low pressure carb fuel system (6-8 psi)? I don't know a lot about carbs, but I assume 470 means 470 cfms? That seems to me like its kinda small for a small block v8... I could be wrong though.

Or the most obvious question... is the carb tuned properly?

 

Where did you get a LSD for the front?

 

First of all, the holley needs to go. You need an Eldebrock Thunder series. Try to stay under 400 in size. Also, sounds like it needs to be geared around 373 to 411. If you know someone good with holleys, they may be able to adjust it properly, but it is unlikely with the size of the carburator.

 

to be more specific on the problem; half throttle in highway driving up hill, the truck sputters a bit and seems to want more fuel. the same goes for when i stomp on the gas instead of feathering into it (sometime even then). this is why i think its the jetting, maybe the power valve, or could it be my carter mechanical fuel pump. WOT on flats/downhill or after 3,000 rpm, the truck runs its best. it likes full throttle. i can feel the vacuum secondaries come in at about 3,400 rpm at WOT. 1st/2nd gear pull hard and when it hits 3rd it falls on its face. right now i have the overdrive switch off. the cfm of the carb when calculated out to the motor (500 cfm) was closer to 470 then 670 truck avenger. that's why i went with the small one. plus i wanted better feul economy, but running with a lead foot all the time isn't helping any. also when hill climbing there is no power and the motor is running hard. could this be something wrong with the tranny? i had climbed the same hill, with the same gears(3.91), with the V6 in the truck. this is why im so baffled. V6 had more torque than this built V8? im hoping that it isn't the compression or the heads (maybe i polished to much). i know if i get some dome pistons it will help a bunch but i don't want to have to go that far if i don't have too. thanks again. Mahalo & Aloha

 

what does the cam spce out at also what pistons and how much bore also sounds like dish pistons sounds like you did what i did on my heads i have no problems and im running my stock tbi what distbutor do you have in it

 

Edelbrock Performer-Plus Cam and Lifter Kits

 

sounds like your having fule problems the heads should not be a problem scince yore running a carb 670 should be enughf did you try tuning an adjust the floats you cant take a carb out of a box and expect it to work rite also check the distbutor shaft for play. you should have amied for higher compresion or do you plan on n2o or boost

 

maybe a turbo later. my friends dad has them laying around the house.

 

there is no vacuum leak. but i think it is the compression being so low. if i get dome pistons will i need to change the carb.