I'm thinking about keeping my 82 z28 stock as far as appearance, and even engine appearance, but I do want to build it some, i'm going for the 240 range on horsepower, and well, as much torque as I can get with modified cfi, mods hopefully will include, hiflow cat, heads, cam, and most likely alot of porting, and throttle body work. if any of you out there have built cfi, I'd like to hear some ideas, tried or not, but with the stock manifold because I like my active scoop hood. oh yes and also what about the ecm? would I be able to upgrade it to something newer? how easy is it to burn chips for stock? well, get back to me I'm anxious to hear some ideas.

 

240 HP from a CFI shoud be no problem at all. Headers, exhaust, and requisite fuel presure and timing adjustments will get you pretty close to that number. A ported intake on top of that will putyou there easily. Don't worry about the throttle body unless you increase displacement; you will see little to no gain. Remove or modify(grind) the "swirl" plates under theTB's though.

These cars respond incredibly well to exhaust mods, because the stock system is total garbage from the cylinder heads to the tail pipe. Get headers and Y, an '86 or newer cat, and a good cat-back system, and you will be very happy. With exhaust, timing and fuel presure tuning, a 5 speed, and 3.45 gears, I ran a 14.5 w/ my old original 305 years ago. I believe your car has a 3 speed auto and a crappy rear gear to match the non overdrive trans. That is going to hurt your performance.

 

yeah those gears are one of the first things I want to change. and actually I think the car already has aftermarket exhaust, it has dual mufflers, with an equalizer pipe that goes between them I thing, and it looks like 2 1/2 inch pipe all the way back from the y-pipe, put it looks like they just put the original cat back in or mabee i'm wrong, cuz it wouldn't most likely fit very well, but I do definately need a new y-pipe, and headers.

 

Yea, that exhaust you have is the stock system. The two mufflers, the "equalizer tube". No good. I used to have that on my car too. Trust me, you don't want it. Your cat is a 2" unit. The newer ones are 2-1/2 or 2-3/4, I can't remember which, but that is the one you want.

 

Another cfi guy here.

I took it a little further. Headers, true dual exhaust, ported intake and heads, crane cam, bored throttle bodies and upgrade ecm.

Another intake option is the x-ram. It's not a crossram design but it replaces the stock crossfire intake and give the crossram appearance.

http://www.alltel.net/~plett/Crossfire.htm

 

I wonder how hard it would be to get them to start a CFI board here on thirdgen. It seems that everytime anybody tries to talk about CFI on the TBI board here they always get flamed. It hasn't happened in the thread yet, but I'd say it will if it goes for a while.

Tom 400 CFI should be the moderater.

 

I was at about 325 HP with mine, and ran 13.7s.

Early BBC injectors. stock vette early AL heads
Com cam 270, 355, Edlebrock headers. walker single 3". 1/4" spacer for manifold lid, cut out EGR tunnel, cut runner roofs back 5/8" 2" butterflies GM Pickup ecm, and my own chip.

this was like 5 years ago using poor ecm programing info.

 

About the ported intake - I understood the passages were kept small to keep up the velocity of the intake charge. In your pics you opened the port almost double the original size. How did this affect performance? Won't that slow down the intake charge at that point and possibly cause fuel to separate from the air?
I'm still trying to figure out the CFI before I start messing with mine!
Thanks for any info!
Rob

 

Hey Keith,
Thanks for the Moderator vote! Though a CFI board would get very little traffic. I'm not sure it would be worth it on this Forum. IMO, this whole board should be re-organized into:
Body/Appearance
Drivetrain/Trans
Suspention/Brakes
Induction
Engine-mechanical
Exhuast
ECM

Right now the way this board is set up, there are two problems w/it (IMO);
1. It's too Clicky. TBIer's on one board, TPIer's on another. Carb folks on their own and 6er's off by themselves. It doesn't matter what system/engine you have; the theory is all the same.
2. Because of the non diversity on EACH seperate induction board, there is a lack of mixing of knowledge and creative ideas. In other words, if someone posts a question on the TPI board, they are going to get replies (for the most part) ONLY for other TPIer's. The poster is missing out. That person could get a more diverse opinion on a general induction board, and more chances of hearing an original, creative idea. The theory is all the same. There are my thoughts.

To Ops32; After the exhaust system(on the Camaro/TA), the stock CFI intake is the next most restrictive part. If you have done exhaust mods (headers, cat and cat back) then you will definitely find a nice gain by porting the intake and modding the swirl plates as Dan's (loinsden) website above shows. Or removing them as I have done. You will not notice a loss of lowend torque or driveability. Here is why. Even FULLY ported, the CFI runners are still WAY TOO SMALL! If you port out the runner untill the floor, walls and ceiling are paper thin, the cross-sectional area of the runner is still going to be smaller than the cross-sectional area of the port in the cylinder head! So your head port is bigger than your intake runner. If there IS a loss of lowend torque from porting, it is so small, and/or it occurs at such a low RPM, that you will not even feel it. But you WILL feel a huge improvement from about 3000 RPM to 5000+ RPM. Turning a stock CFI motor above 4300 or so is pointless.

I can't give you hard numbers on the improvement I saw in my car from porting, because I ported, bored the TB's and installed a larger fuel pump and injectors all at the same time(on the SB 400 and cam that are in my sig along w/ the header and exhaust I already had). The numbers I saw were a 1.8 sec improvement in the 1/4. But that is because the big 400 was startving for air AND fuel prior to the port job. But a friend of mine w/an '84 CFI Vette was running 15.5's - 15.8's(at 4500 elevation). He is a very regimented, technical driver and the spread in times was purely a result of the engine. The car is bone, box-stock by the way. He ported the hell out of his intake(paper thin walls), removed his swirl plates, bumped his fuel presure, and promptly started running solid, consistent, 15.1x's! (at 4500') That is a huge bang-for-the-buck improvement. $50.00 in gaskets, and over a 1/2 sec improvement! This examle illustrates how restrictive the intake is when box-stock. Everyone that has a CFI should port their intake, in my opinion.

 

I'm guessing the reason the boards are setup the way they are is to keep flaming to a minimum, most carb or tpi guys have something against tbi and cfi, and the other way around also, people forget we should remember the thing we all have in common and that's f-body's and as for induction and engine choices, to each his own. and well the 6 cyl guys, I don't think anyone likes them much, but then again most people don't like 305 guys such as me, I get sh*t for it all the time and that's mostly in real life. I happen to like my 305. and it's not the first one I've owned, well actually it kinda is. lol, but that's another story.

 

and another thing if any tbi guy tries flaming me I'll get pissed, cuz cfi is tbi. and I would just think that they are jealous of my cool active scoops, and air cleaner. lol

 

cfi all the way guys!!!
i have seen tom 400 race at rmr when i wanted to enter my car for the wednesday test and tune! his car is the sh*t cfi. tom u still need to give me soem pointers on cfi and how to mod the hell out of it! i used to be recaroxfire on this board.
my cfi is pretty damn fast for a cfi and at 4500 i can proably pull 15.1's!

 

Thanks for the info Tom!
Rob

 

I think the TBI board should be re-categorized as CFI/TBI because they are similar systems. What seems to be happening now is a cross between CFI/TBI right now.
The new designs are high-rise runners and TBI units, but if you take a look at the CFI systems, they are remarkably similar, but very restrictive.
The CrossFire has been put down because of its restrictions. That website about porting all the CFI intakes makes me think they are doing the right thing entirely!
Even taking the CFI system and crossing it with the TBI ideas will make us develop a new TBI/CFI compatible system that will make the other boards look at us more seriously.
The problem is opinion. We get the brunt of it because we are TBI or CFI all the time.
Maybe we should start to design something that is better than what is out there.
That is how it works. Let's get the attention again. There are a lot of good ideas, and we can work together instead of hammering each other saying "This or That" won't work. How do you know?
You can't make progress with destructive criticism in the first place. Let's stop and think about the induction systems we have and make the most of them! A new idea isn't always a bad one!
Hell, I wouldn't have gone as far as I did if I didn't have a little imagination and foresight.
What really works? Let's engineer!
That is what we do!

 

By the way, has anyone ever seen the Edelbrock Spider Ram low-rise manifold? I seem to remember that one from years ago... I am wondering if it still exists...
It has the runners running out and around perpendicular to the engine rather than up and down....
I was thinking about that when I was posting my last message.
It's an idea.................

 

i think cross fire fuel injection is kool
because 1. it's rare 2. its got 2 throttle bodies 3. it looks kustom!
everyone at my school thought i had my car custom to make that sort of a set up, everyone feared my car until they heard it was a 305, that pissed me off. so now my mission is to show everyone what a beffed up cfi 305 can do. if anything guys lets just keep posting stuff about cfi and get the boards attention. also it would be awesome if tom 400 showed me some tricks to beef up a 305 since hes the only one who lives in utah too!!
cfi will live on!!!

 

I'm a fan of CFI. 84 Vette has a pretty cool setup. Makes plenty of torque, but lacks a little on top end. Nothing a little porting to the intake, or an X-Ram, or an Offy couldn't fix though.

 

I hate that, when you say 305 people laugh, i know how it is, but a 305 is a dang v8 and they can be built, personally I won't get rid of mine I plan on building it.

check this out, this site dogs on cfi some but it's a good site for 305 enthusiasts.

http://www.goingfaster.com/spo/modthel03.html

 

My formula will hit low 14's high 13's with a 305 and with TBI some day! Well it will have the 305 block anyway. When it comes time for this engine to be rebuilt it will be built for 300hp.

It would just be cool to hand a LT1/LS1 it's *** and then show them what's under the hood.