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Topic: SEFI conversion to MAS (Read 8773 times) previous topic - next topic

SEFI conversion to MAS

Reply #45 –
Quote from: 20thanvcat;459938
The pcv is located in the back of the lower intake  but both valve covers are essentially open to the atmosphere -- so i should have the tube from the tb to a valve cover and seal the other ?

Yes. Cap one valve cover and run a line from the other to the throttle body nipple, like stock. As stated above without the line the computer's load and air/fuel ratio calculations will be off.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

SEFI conversion to MAS

Reply #46 –
anyone have pics of how they set up the tube from the throttle body , i see some fittings that look like hollow pcv valves into a grommit - and i have seen them into a nipple on a stack with what looks like a filter - that would still be open ?

SEFI conversion to MAS

Reply #47 –
Either will work. Doesn't matter how you do it as long as you close the loop. Seeing you have aftermarket valve covers I would use the breather/filter type with the nipple on both covers and Tee them to a smaller line to the TB.

I drilled and tapped mine and theaded a barb type fitting in.....Tied it all to catch can then back to the TB before I changed things up and went turbo.

John

SEFI conversion to MAS

Reply #48 –
ok now you just threw a wrench into the mix --i have twin turbo set up but i wanted to get it running correctly first , your saying there is a diffrent setup for turbo ?

SEFI conversion to MAS

Reply #49 –
If I were going to run a turbo setup, I'd run speed density instead of MAF.  There a a number of really good reasons why SD is better for Forced Air, you can do your own research.  I will say, since I'll assume you're familiar with EcoBoost, that ALL EB engines Ford builds are speed density.  It looks like they have a MAF; but it's a MAP, 3 of them to be exact.  One in the inlet duct, one between the turbo(s) and throttle blade, and one in the intake after the throttle blade.

SEFI conversion to MAS

Reply #50 –
The PCV system only needs to be modified if your set up is configured as a blow-through Maf arrangement...... You will need to get creative to keep from pressurizing the crankcase. If draw through......You only need to relocate the TB line somewhere after the Maf and before the turbo.

Now that we know where your going.........I have to tell you that 24# injectors won't cut it and tuning in my opinion is mandatory unless your intentions are track duty driving only.

I agree with the above post about running a SD system but you can't compare today's tech to what's available for these old cars. Seeing as your going to require a tune eventually I highly recommend you spend your money on any of the Megasquirt PNP options including the PIMP from Stinger. Believe me by the time you spend the money getting it to run right on the stock ECU......You will be kicking yourself for spending more than you needed to.........Yup, I'm still kicking myself but Im a bit OCD and got things working very well with MAF and tuning the stock ECU myself.

John

SEFI conversion to MAS

Reply #51 –
Ok replaced 84-85 valve covers (butterfly type oil cap) to newer style grommet sealed type, installed a tube from throttle body to valve cover (cut the bottom off a pcv valve ) and went back to stock air cleaner box - waiting on a collor to connect mass air to air cleaner box - then ready to take it for a ride -also recoleaned and covered ego harness and bought new egos ==hope this works ;):punchballs:

SEFI conversion to MAS

Reply #52 –
update -- it is amazing what a little tube from the intake to the valve cover will do as far as performace ----many thanks for all who gave input , car runs so much better , only problem now is tires are more expensive to replace --but thats a good problem (oh yea now heater core is leaking --oh well )

SEFI conversion to MAS

Reply #53 –
That little tube is very important in a MAF system as you have found. Sometimes it's the little things.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

SEFI conversion to MAS

Reply #54 –
yes - im very old school if it has a carb i can make it run , but this fuel infected is a whole new deal , and to modify it even more diffacult . again thank you for all your input

SEFI conversion to MAS

Reply #55 –
It's easier than switching a bunch of shiznit over to a carb, though. At least, it is if it's already SEFI...such as an '87 or 88 Tbird 5.0....

Say you have an '88 Sport. It's already got the efi 5.0.....you can upgrade it easily. Change the EEC, run yourself a wire for the mass air meter back to the eec, and drop in the new/upgraded engine. Nothing else needs to change.

My big riding mower is even fuel injected....love it. starts up in the coldest or hottest days, never vapor locks, and even has a provision for priming should it run out of gas.



My first ride was carbed, had points. I quickly learned to keep a few sets of points in a zip lock bag, along with a feeler gauge. Yeah...that shiznit sucked. 24 years later, I can still remember dealing with the leaky carb always needing adjusted. No thanks. lol
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

SEFI conversion to MAS

Reply #56 –
Quote from: 20thanvcat;460288
yes - im very old school if it has a carb i can make it run , but this fuel infected is a whole new deal , and to modify it even more diffacult . again thank you for all your input

I've never owned anything with a carb so EFI all the way for me. Heck the EFI on a Fox car is much more primitive and easier to work on than the modern stuff.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.
 

SEFI conversion to MAS

Reply #57 –
I bought my first car in 1966 and can say, compared to EFI carbs are a PITA!!! Of course if one won't take a little time to learn the basics of a old EEC-IV system a carb may look pretty good...  Yes most carbs are simple, but they won't begin to give the drivability of FI, especially in the first 10 minutes or so of a cold start... That shiznittin' little Comet is just pure evil when cold but to be fair the heads don't have heat risers, really isn't something I want to think about driving if under 50*...