Hey guys,

I just sent my engine in to the machine shop Wednesday morning. I'm having my stock 2.8 V6/60 rebuilt into a 3.1 V6/60 with a performance camshaft. The pistons are also .030 overbore so it will actually be a 3.1 liter.

Now, my question is that... I need new injectors I'm assuming. I'd like to have the additional fuel now that my engine will be a 3.2. I still have the stock 2.8 fuel system. What do I need to do to upgrade it to the 3.1 fuel system? Are the injectors in the Camaro 3.1 different than the injectors in the 2.8 Muliport Fuel Injection system?


Thanks!

 

I belive they are as the parts store has two different #'s

IMO
2.8=13lb injectors
3.1=15lb injectors
3.4=17lb injectors


Also, if you have the cash, dont get stock ones as I have heard time and time again they are POS

Think it was wayne on here that gave me summits part # for the accell 15lb injectors, if you wish, I will pass it on.

 

BTW, I now have a set of each, the 2.8,3.1,3.4l (2sets), all look different also!!!

 

GO TO ANY FWD 60* V6 for these parts.
I can say that the FUEL INJECTOR HEADS of my 3.4 injectors look like a shower head.
Multitec I think it was called.
My 2.8 ones look like Pintle style.
Yes, I install the 3.4 injectors onto the 2.8 rails of the 3.4 Firebird swap.
It was common sense to me & a newer part, too.
I also can say there were two-three suppliers for the injectors.
AC & Bosch, perhaps, Lucas, also.
I believe 1987 was the cut off year.
Exact applications, I'd say find same size FWD car & send out to be cleaned for the $6/injector.
The guy is in Jersey.

 

Does the 2.8 really come stock with 13 pd injectors ? I thought it was 15 and I have my 15 pd accels in there . Well , my 15 pd accel ones work fine in the car ! Maybe thats why I knowticd a little more pep with those new inectors huh ?

ACC-150615 15# accel injectors ( six in a pack)

 

According to STOCK figures.......


2.8
(125x.50)/(6x.80)=13.02lb

3.1
(140x.50)/(6x.80)=14.58lb

3.4
(160x.50)/(6x.80)=16.66lb


I guess for 82ta, heres how you do it

(est hp x .50)/(injector quanity x .80)=lb needed

 

After checking that chart, I'm glad I used my 3.4 injectors.....
It just made common sense.

 

That's weird.... the V6 in my Fiero puts out a factory hp rating of 140hp and 175lbs of torque, and it's a 2.8 V6/60, not a 3.1.

You mean the f-body 3.1 V6s only put out 140 horsepower?


Todd

 

Correct. I belive the TB on the fiero was bigger creating more power. I belive the exhaust was little less restrictive also?

But that is the figgers I have found on f-bodys.

 

It was all gained in the exhaust work.
Shorter, better flow exhaust manifold set up.
WANT TO SEE 5-10 HP?
Open F Body hood, go to passenger side, look straight down.
There sits a 5-10 HP gain you really can feel once that restriction is freed up.
there is no difference at allina Fiero engine and an F body engine.
Nothing is bigger nor smaller except the exhasut system.
Fieros got very lucky plus add weight transfer, it is a very quick ride.
FWD mills got very lucky, they had great cylinder head & intake set ups.
3rd gen V-6 got "left over engine designs"
BUT REALIZE, the MPFI set up is very, very well designed.
It works perfect, as is, just adding the 3.4 injectors to the old 2.8 1985 MPFI induction design.
That's impressive.
There's room for "more" but 200 available foot pounds of torque really makes this as-is system shine. Just add more fresh air coming in, not opening the TB size.
There is no size difference between a Fiero TB & a F Body TB nor the same vintage FWD design TB stuff.

 

Dale, yeah, like was mentioned, the Fiero exhaust manifold was basically a length of pipe, with three pipes welded to it. Fiero owners could see a gain by doing some grinding to the stock manifold- there was leftover "weld" where the factory welded the 3 pipes to the single head pipe. The 3 pipes actually protruded into the main pipe, so by grinding them so they were flush with the main pipe, they could find extra power. I also read on some web pages that those manifolds were prone to warpage, causing exhaust leaks. 'Fact I think that was one of the "fire" recalls...

If you ever get one of our exhaust manifolds in your hands, you'll see there's no "miracle" spot to grind in. The whole thing has to be ground out.. and in some spots, the factory casting is pretty thin.

 

Yep, I have a set of ours. Infact you were to load a program for me to edit pics so I could modify the extra set I have .

In no hurry, why modify manifolds if the car dont run right in first place?