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Topic: 3.8L Mechanical Fuel Pump interchangeability ? (Read 243 times) previous topic - next topic

Re: 3.8L Mechanical Fuel Pump interchangeability ?

Reply #15
From the '94 T-Bird shop Manual 3.8L V6:
RWD, Roller Cam, No Balance Shaft, Sequential Multiport Fuel Injection, Injectors in the Head above the Intake Valve,,
Removable distributor drive gear on front of the cam shaft, Part # 6255
Bolt/washer on end of cam shaft, Part # N806049-S2


 

Re: 3.8L Mechanical Fuel Pump interchangeability ?

Reply #16
84 Shop Manual 5.0 V8 camshaft.
Fuel pump eccentric part # 6287

Re: 3.8L Mechanical Fuel Pump interchangeability ?

Reply #17
84 Shop Manual 5.0 V8 camshaft.
Fuel pump eccentric part # 6287

softouch, foureyedpride.com member "xctasy" said something about the cam walking on the later roller cam motors (89-04 ?).
 I'm not sure what he means there.  You seem to suggest the 5.0L eccentric will swap over to the 3.8L, yes ?    
Next, I'm still not certain what you all are talking about in reference to "balace shaft".  I'm guessing some 3.8L are internally balanced and some are not ?  My link on FEP.com mentions a weight on the shaft. I'm just not familiar with style balancer.
Last, from me analyzing all these comments, I think its safe to say that all 82-88 will drive the mechanical pump without any extensive modifications. All that needs to be done is cutting a hole in the timing cover on the 84-88 to fit the pump arm to the eccentric.   Is everyone in agreement ?


Re: 3.8L Mechanical Fuel Pump interchangeability ?

Reply #18
Quote
softouch, foureyedpride.com member "xctasy" said something about the cam walking on the later roller cam motors (89-04 ?).
 I'm not sure what he means there.
  I don't know what it means either.
Quote
You seem to suggest the 5.0L eccentric will swap over to the 3.8L, yes ?   
don't know if it will work or not. Just threw it out as a possibility. 
Quote
Next, I'm still not certain what you all are talking about in reference to "balace shaft".  I'm guessing some 3.8L are internally balanced and some are not ?  My link on FEP.com mentions a weight on the shaft. I'm just not familiar with style balancer.
Some 3.8L engines have a balance shaft. They have a gear on the front of the cam shaft that drives the balance shaft. The shaft runs parallel to the cam shaft and rotates in the opposite direction. They seemed to be only used on FWD cars. If you are going to try to use one of the newer roller cam engines I recommend picking one from a RWD car.
Quote
Last, from me analyzing all these comments, I think its safe to say that all 82-88 will drive the mechanical pump without any extensive modifications. All that needs to be done is cutting a hole in the timing cover on the 84-88 to fit the pump arm to the eccentric.   Is everyone in agreement ? 
Not the 88 make that 82-87. I would not be surprised if the pump hole is still in all of these 82-87 engines.



Re: 3.8L Mechanical Fuel Pump interchangeability ?

Reply #19
So I re-read what he was saying.  The cam retainer is different on roller cams and thus if you modifiy the cam with an eccentric, it will want to walk. Then he said something about making sure the distributor gear being strong enough to handle back fire.
Next, I researched  google about the balance shaft.  If someone were to upgrade to a high lift cam that made vibrations, would the balance shaft also have to be modified ?  That seems like a bunch of bull $#!T ...... the more I read, the more I like the old engines better.  It seems the 99-04 Mustangs have balance shafts, as far as I can tell at this point.  Not sure about the other years or models. I guess I'll be researching that next.

Re: 3.8L Mechanical Fuel Pump interchangeability ?

Reply #20
Balance shaft in '88, and then not again until '99. It's in the Babcox article I linked.

Re: 3.8L Mechanical Fuel Pump interchangeability ?

Reply #21
So, with out going back and reading your previous post...89-98 are not balance shaft ?   Sorry, to drunk to research at the moment.   Thanks by the way !
EDIT: Also, if 89-98 are not balance shaft...can someone just delete the balance shaft ? So in other words, just delete it ? Making the block emulate an earlier block ?

Re: 3.8L Mechanical Fuel Pump interchangeability ?

Reply #22
RWD, Yes. None of them have balance shafts. The article I linked (I have no personal knowledge) says the unfinished balance shaft bores exist without oiling holes.

Maybe? However, I think you'd need to cap the oil passages for the balance shaft.

What exactly are you trying to do?

Re: 3.8L Mechanical Fuel Pump interchangeability ?

Reply #23
When I looked up 3.8L balance shaft on google, it shows 99-04 Mustangs 3.8L have balance shafts. Those are rear wheel drive cars.
What I'm trying to do is find out what takes to carburate late model 3.8 engines.

Re: 3.8L Mechanical Fuel Pump interchangeability ?

Reply #24
As best I can tell, to carburate a 99+ 3.8, you need an electric pump for fuel,  an intake, and a distributor. The balance shafts are red herrings.

You can get an intake from SuperSixMotorsports or Tom Morana.

The 99+ 3.8s don't have a distributor, but still use a cam position sensor that uses the same spot as the distributor in older motors that sits in the timing cover.



The timing cover gasket interchanges between '94-'04, so I'd guess the interface between the timing cover and cam stayed the same. You may be able to use a carb'd distributor. You'd have to get your hands on a '99+ camshaft synchronizer to confirm the dimensions.

SuperSixMotorsports and Tom Morana both have EFI-to-Carb kits for the 3.8. I'd just ask them what the deal is and if you could use your own distributor if theirs is too expensive for your blood.