CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

'90 burb getting a 383: which fuel system?

You make a good point . . . And now you've got me thinking.

I could also do a L29 and still probably b be less expensive than a 383 while probably making more torque. Hmmm
Unless you put a lot of wheaties in that 383, an L29 will make more torque
 
the brand new gm L31 in my k30 tips the scales at 7k lbs and has 4.10 gear and 33.0 tires . she does just fine for me for the most part and the pro flo 4 does good .

some steep long hills and heavy trailer load slow me down a little . but i am in no hurry .

and they say the 383 cam wakes them up a lot for just the cam swap .
 
Not that I’m against spending money, but if I were budget minded I’d stay small block, going big block will $20 you to death with the little things like motor mount swaps, different exhaust, starter?

it’s not a hard swap, but it’s going to add cost.
 
Not that I’m against spending money, but if I were budget minded I’d stay small block, going big block will $20 you to death with the little things like motor mount swaps, different exhaust, starter?

it’s not a hard swap, but it’s going to add cost.


Good point, I figured with a big block I'd need a new exhaust. But I hadn't thought about motor mounts, starter and whatever else pops up.

Plus I'm already skeptical my tranny will hold up too long with a 383, that BBC torque will probably bring on a new transmission much sooner.

I haven't really seen any negative comments about the pro flo, so I've almost convinced myself to bite the bullet and just do it . . .
 
the brand new gm L31 in my k30 tips the scales at 7k lbs and has 4.10 gear and 33.0 tires . she does just fine for me for the most part and the pro flo 4 does good .

some steep long hills and heavy trailer load slow me down a little . but i am in no hurry .

and they say the 383 cam wakes them up a lot for just the cam swap .

With the 4.10's & 33's what kind of RPM are you running at 75mph? I've still got 3.42's and wasn't sure if I should go to 3.73s or 4.10's since more than half the time I'm cruising down the intestate or highway at 75-80mph.
 
With the 4.10's & 33's what kind of RPM are you running at 75mph? I've still got 3.42's and wasn't sure if I should go to 3.73s or 4.10's since more than half the time I'm cruising down the intestate or highway at 75-80mph.
So my truck 700r4 4.10s and 33" 55 was 1600, iirc 65 was almost 2k. and no power to pass. I went to 4.88 now 55 is 2k and 65 is 2500. 3.42 with 33"s imo will be a dog until you get to 75 mph which is @1820 rpm locked in 4th
 
For those of you that have converted from TBI to pro flo 4, have a look at my parts list please. Am I missing anything? I've messaged @folkenheath and will be placing an order later this week.

upload_2020-9-30_12-6-54.png upload_2020-9-30_12-7-35.png

I'm still making my mind up on whether to go with the 350 vortec or 383 vortec . . .
 
If your coming to Spokane for an engine build. Also talk to Cassell. I had them do my last 350 long block. Good work and reasonable.



Cassell Engines
(509) 484-8453
 
A few question, do you have good plug wires?

What are you doing for a fuel pump? I recommend swapping in a walbro.

I would also get an adjustable regulator rather than that somewhat expensive non-adjustable unit, but that one will work.

The 383 is going to give you more torque and hp and shouldn't cost much more really if you are already buying a new crank.

Long tube headers will give you more torque and power than the shorties. You will need a pair with an O2 bung or weld one in.

Are you sure those are the right fittings? I thought they were the 3/8 and 5/16" o-ring EFI connectors, not metric? But I have not swapped from a TBI before, just carb, so I am not sure just suggesting you double check.
 
Those look like the same TBI/AN fittings I added at my fuel sender, then ran braided line to and from
 
A few question, do you have good plug wires?

What are you doing for a fuel pump? I recommend swapping in a walbro.

I would also get an adjustable regulator rather than that somewhat expensive non-adjustable unit, but that one will work.

The 383 is going to give you more torque and hp and shouldn't cost much more really if you are already buying a new crank.

Long tube headers will give you more torque and power than the shorties. You will need a pair with an O2 bung or weld one in.

Are you sure those are the right fittings? I thought they were the 3/8 and 5/16" o-ring EFI connectors, not metric? But I have not swapped from a TBI before, just carb, so I am not sure just suggesting you double check.

- I already have a Walbro GSS342 on the way.
- Any suggestions on an adjustable regulator?
- Those shorties already have an 02 bung, and the rest of my exhaust is fairly new. But it may be worth looking at an overhaul there . . . .
- Based on what I have read on other threads here I think those are the correct fuel line fittings.
 
For Edelbrock I would use a 1728, Holley a 12-880. The Holley 12-886 is a lot cheaper though if you don't mind the NPT threads, I prefer the o-rings with the high pressure fuel. All of these would allow you to put the regulator after the fuel rails.

The Edelbrock one you mentioned would probably work fine too I just like to have the adjustable one after the rails in case you want lower pressure for better fueling at low speeds or higher pressure if you need more flow for more power down the road. Now you can decide which one is right for you.
 
That edelbrock regulator in your list is vac referenced for low/high psi as the system needs it .

List looks good . I just don't like open element air cleaners sucking in all the hot air . I reused my stock g. Closed unit and duct tube to the correct support flange and it works great .

And if I recall its 10 micron filter size required . Make sure the filter can do that .
 
I agree, every regulator I recommended has a vacuum/boost reference port as well. It helps to lower the pressure it idle and low load for better fuel injector resolution. Essentially is equalizes the pressure difference between the fuel rails and intake manifold so it's pretty much always the same delta.

Although it's not always necessary as many people run those fixed pressure Corvette style filter/regulators without issue. And some run fixed pressure regulators in the fuel tank where you can't vacuum reference it.

But it is one of the reasons I like a seperate adjustable regulator, they usually have that reference port.
 
Last edited:
I installed the fuel pressure regulator at the end of the fuel rails, the return line connects to that. The fuel pressure sensor is at the inlet. So far, I haven't had a problem with any leaks. The O rings are easy to replace if necessary.
I used those adapter fittings as well, but I had factory TBI lines, so I put the adapters at the frame where the original flex lines hooked up.
 
For those of you that ran new fuel lines from the factory TBI hardline on the frame rail up to the flow pro fuel rails; would 10ft of fuel line be enough for the supply and return line?
 
For those of you that ran new fuel lines from the factory TBI hardline on the frame rail up to the flow pro fuel rails; would 10ft of fuel line be enough for the supply and return line?
It should be more than enough. Obviously your routing makes a difference, but I think that I used less than 8 feet of hose to get to the front of the fuel rails.
 

Latest Posts

Top Bottom