well i told my friend the other day about my 83 z28 and when i told him its cfi he looks at me in shock and says to rip it out imeddiatly and convert it over to a carburator. he said edelbrok intake manifold and carburator should be much much better. is this true, and if so what kind of carb/manifold would fit on my 305? thanks!

 

spoken like a true person afraid of fuel injection. no it's fine. there are many things you can do to get power out of it. here's what chevyhacker and i have done to his car. http://www.technovelocity.com/chevyhackers/

 

Go to a Corvette Forum & talk to them. Many of them have put lots of power in their 84 Vettes that carry the CFI.

As a matter of fact that i was told by a Corvette dealer that we are close to that if anything goes wrong with my 82 Indy pace car with the CFI that I was more than welcome to bring the car there & they would do most of the work cheap.

 

check this link out there has been a rather large post on the thirdgen.org board on cfi http://www.thirdgen.org/techbb2/show...hreadid=190137

 

you have to get past the waste of time people to see what you can do to make a CFI better. also go here. it's a specific CFI board.


http://www.crossfire.homeip.net/

here's a quick rundown on chevyhackers car and what we have done.

http://www.technovelocity.com/chevyh...re_z/index.htm

 

Law of diminishing returns. Without an x-ram you can forget about any horsepower, and as soon as you plunk down the cash for an x-ram you could have gotten a nice intake & carb.

I'm an EFI guy all the way, but TBI sucks. 2x TBI sucks 2x as much, and when it's on top of a super restrictive manifold it sure doesn't get better.

 

Heh I didn't know you posted here too Jim.

I completely agree. IMHO modding out a CFI for power is a waste of time. Not to put down anyone else who has.

 

I post everywhere dude.

There are a bunch of guys on the corvette forum (yeah, I post there too) who run the x-ram. A couple might be running 13s after spending a ton of money on various crap. It's just not worth trying to work around such a major obstacle. It's like stroking a 305. People do it just for the sake of saying it can be done. I do things for the sake of going fast.

 

it doesn't take long for the waste of time people to show up on this subject. don't know why. the only thing limited you can buy is an intake for it. currently there is only the x-ram. but everything else you can buy for the CFI (cam, heads, exhaust, etc...), is the same for any other motor.

the same thing can be said about TPI. unless you buy an expensive Accel Superram, Holley stealth ram(not as expensive as the others), TPIS miniram, you can't get past the 4800 rpm wall. so compared to a LT1 or LS1, they are junk as well. the crossfire intake has the same runner design as the TPI. just a different way of introducing the fuel and air.

again like i said, you'll have to wade through the waste of time people to get the answers you are looking for. just keep checking on chevyhacker's car. we picked up 1.13 secs on doing headers, 3" cat, 3" catback, and ignition tune up. another .35 on the converter and porting of the stock intake. the only thing we have spent money on was the porting of the intake. and that was a gasket set at that. so, everything we've done to it, is the same thing you do on all other motors, regardless of induction.

the week of the 19th to the 26th, we are swapping to world products heads, comp cams 268xe cam and lifters, and 1.6 roller tip rockers. again all the stuff you would do on any other motor. looking for high 13s on a 305 CFI. stay tuned.

 

Just because an engine can't rev high doesn't make it a slug. A Caddy 500 cui can't rev high, but it can run like a monster, turn very low ETs and can be built relatively cheap. Are they a waste of time too?

The problem w/saying a TPI is a waste of time is the fact that (at least w/the 350) they can run 13's w/minor bolt-ons costing the owner a very minimal investment of cash . Can that be said of the CFI 305? You're dumping how much cash into a 17-16 sec (sounds like Honda Civic ETs) drive train to make it run 14's...maybe high 13's? A TPI engine is a far better starting platform.

 

agreed anything CAN be done i could take an old geo metro and turn it into a 10 second car but thats not the point. The majority of people on this board are just your regular run of the mill car enthusiasts and while some are on budgets and some arent regardless why spend 5000 dollars on a project and get certain results when you could spend 2000 dollars to get the same results by going a different way. I dont know enough about cfi to get into an arguement but i think what this person wants to know is bang for his buck is it worth modding a cfi or should he switch it out to something different. I really dont think this post was intended as a "what can be done" but what the hell should i do to make my car faster and if youre going to tell him that he should go one way even though going another will get the same results for spending less then either your an *** or theres something wrong with you.

 

Exactly. Once you buy the x-ram, new throttle bodies, new heads, new cam, new exhaust and somehow figure out how to make the computer understand what you did, you will still have a slow 305.

Nobody is trying to say that you can't mod these cars... it's just that it's not cost effective.

If horsepower is your primary concern, CFI is not a good platform. If you just want to **** as much money into an antiquated induction system for the sake of saying "Look what I did", then by all means have fun with the CFI.

 

again, all you can do is concentrate on the CFI part of it.

greed - my point was just to show that any type of induction has it's limitations. i run a TPI. and without spending at least $700 on runners and base, you don't get past 4800 rpm.

can a 305 TPI run 13's with minor bolt ons? at least compare same motor. not without doing the same thing as we have done with the CFI.

oh yeah and when we do run high 13s on a 305 CFI, don't want to hear "you could've run faster with a 350." we have an 82 corvette for that.

gee, once you buy new TPI intake, throttle body, heads, cam, exhaust, get computer chip burned, you still have a slow 305 TPI. what's your point?

 

okay since no one is being helpful im going to rephrase the question for the person who started this post and make it more clear. He has a 305 cfi...is it cheaper to mod the cfi or switch to carbed based on achieveing the same sort of performance?

 

Oh it's crap alright. You should sell it to me for cheap.