efi or carb?

[whitepony]

ok my set is just plain and simple

ford F-cam, under drives, portred stock intake, with stock ported and shaved heads 3.73's.

but with winter coming i bought a set of gt 40ps and an explorer intake, and a holly highrise.
the heads are getting done as we speak ( 3 angle valve job and ported and shaved )
but anyway to my question will i make more power with those heads and the efi intake or with those heads and my holly highrise and an edl. 650 carb ?

anything will help thanks

mike

[crazypete]

I think the general consensus has been that EFI makes great bottom, great middle and good top end and a carb makes good bottom, good middle, and great top end but it's more finicky about things such as weather and altitude and humidity. I remember seeing a graph that MM&FF did once when they did a carb swap on a stock fox 5.0. The EFI hp/torque curves were completely smooth and the carb curve was all ripply. The carb curve was slightly below the EFI curve until it hit 4000 (????) and then the carb curve went above the EFI curve. This is off the top of my head.

So to answer your question:
1. More street power with the efi (low-midrange)
2. More race power with carb (high range)

All that said, I swapped my EFI out for a holley and I will never ever look back. If you're doing mods regularly, a carb is the way to go. EFI needs to be recalibrated with injectors, mafs, fuel pressure regulators and sometimes even a programmable engine controller. Just look at all the "which ____ go with which ____" threads floating around. Each of those adjustments is a couple hundred bucks. Me, I just go up front and turn some screws and the problem is solved within a few minutes of tinkering for a few bucks in springs and jets. The carb is more "accessible" to the enthusiast. I warmly recommend the holley simply because _everything_ can be adjusted.

Good luck!

[Dark_5.0]

A properly set-up EFI set up like mine .........

Will only go slower with a carb in my opinion. If you have a high flow intake and a big throttle body I think the EFI would out perform the carb across the board and maintane better driveability/reliability.

[crazypete]

I agree, a properly tuned computerized setup specific to your equiptment would be faster. It would just cost much more.

About reliability......

My EFI died 3 times in a year from MAF, ground and O2 sensor problems respectively totalling over $1000 in repairs. Once I got the carb conversion woes out of the way and had it running, the worst that happened to me is that it died once in 2 years. I went up front and sprayed some carb cleaner at it and then started her back up and drove off.

Word.

I think the carb is much more accessible and costs much less to repair and tweak. When something dies on an EFI, all you can do is replace components and these usually are $50-$300 per component

[Dark_5.0]

Originally posted by crazypete
I agree, a properly tuned computerized setup specific to your equiptment would be faster. It would just cost much more.

About reliability......

My EFI died 3 times in a year from MAF, ground and O2 sensor problems respectively totalling over $1000 in repairs. Once I got the carb conversion woes out of the way and had it running, the worst that happened to me is that it died once in 2 years. I went up front and sprayed some carb cleaner at it and then started her back up and drove off.

Word.

I think the carb is much more accessible and costs much less to repair and tweak. When something dies on an EFI, all you can do is replace components and these usually are $50-$300 per component

I really cant argue with your point since I seem to fry my mass air sensor every 6 weeks. It is also alot harder to track down problems on an EFI car.

I plan on doing a 351 swap in the near future and it will have a carb. I dont want to spend 600 bux for an efi intake, 300 bux for 30 # injectors, 200 bux for a new mass air meter and another 350 bux to have it dyno tuned so it will idle right.

If only I were rich

[whitepony]

so from what i read its really the cost to fix everything in whitch i know well cuz i have had nothing but problems with my efi i just cant get anything to work right i dont know why. thats the only reason i wanna switch. i dont wanna switch it over if i will go slower then a 12.9 in the 1/4 b/c my car ran that 2 yrs ago with a set of 4:30's out back . do you guys think that if i was to put my 4:30's in and head to the track on my carb set up i said about that i would go slower or faster or do u think after my heads and my efi intake (explorer) and a 65mm thb that i will be past my 12.9 tuned perfect ( not by me) (gt 40p heads on both set ups with 3 angle valve job and shaved)

i hope that all makes sence to u guys
thanks
mike

[Dark_5.0]

Its going to run very similar both ways. Its really a matter of preference.

[Ieatcamaros]

I'm the guy to tell you to go carb and never look back. I carbed both of my cars and definitely don't regret it. The number one reason is the simplicity of the engine and it's components (easy to track problems). The number two reason, I can change the plugs in 15-20 minutes in my 302 lx. The number three reason, Look how clean the engine bay is!! I have an F cam in my lx and it idles pretty good with that holley atop the engine.

Hey Dark 5.0, when I put the 351 in my GT, that was the main reason I didn't stay efi. Then, I liked it so much, I did the same thing to my brother's car when I got it from him (the 302 lx).

**I would add that, when I swapped the 302 to carb, it didn't make a difference in the a$$ dyno. But now it idles better and sounds much meaner.

[~The Jester~]

I gotta vote CARB. Granted I'm old school, and I understand EFI has better manners and driveability issues. I live in Ohio, and going from 90+ in the summer to -15 in the winter is NOT a good place for a carb. The Horse is tuned for Max summer performance, and the truck is jetted for a "happy medium" so I don't have to keep playing with it. EFI would solve that problem, but IMHO I think it creates more problems than it solves. It's just to quirky, plain and simple. Look at all the "What the hell is wrong with my car" threads in here. IAC this, MAF that, MAP over there, O2 this.

Good luck on whatever you decide!

carb carb carb carb carb. Just my $02 !!!

[whitepony]

ieatcamaros is right it is alot simpler and tunning is so fast, i could then smooth out my engine bay like i always wanted to do..

but i still kick my self in the a$s cuz i just bought that explorer intake. and it would go to wast and i just bought a adj. fuel presure reg. and still have e-tests.
man i am so hung up what i think iamk going to do is do my efi set up then if by like june i dont have it running top i will go out and buy a ed. carb 650 and change overi'll give it one last shot thanks for all the help from everyone i just want to know what is it like to take the wireing harness out and changing the pump over??

thanks agian to everyone

mike

[crazypete]

Well, the best thing to do is to pull up the dash, the drivers kick panel, rocker panel cover and rear 1/4 on the drivers side and rip out all the useless wires front to back. It's a week's project. To just ghetto gut it is real easy. You'll just need to re run the temp guage, headlight and alternator wiring. Now is a great time to remove that mass of crap behind the original battery tray (starter relay and the fusible links) and move it to the other side of the fender to REALLY clean up the enginebay. You'll pat yourself on the back when you are done. Then sneak one bundle of hoses and wires in the driver's side back. Getting rid of the heater plumbing CRAZY cleans up the enginebay too (you probably dont drive it in the winter anyway). Oh yeah, I think the A/C has some clutch controlled through the computer. You'll need to goose this or......rip it out. A/C removal is the definitive enginebay cleaner. You'll lose 100 or so pounds too.

As for the fuel pump switchover, you will need an eccentric of an 85 mustang for the front of your cam and a new timing chain cover (actually, it looks like the efi ones have the necessary fitting and depression on the driver's side of the TC cover, you just need to cut it open in the back and tap it for bolt holes). The actual pump can use your existing fuel lines. Take the return line and decouple it near the passenger side sway bar attachment point and cap it off. Take the supply line and forward of the first coupling (near the same sway bar attachment point) and hacksaw the steel fuel line and slip some hose over it and clamp. Then run hose in front of the oilpan. This setup has worked 2+ years for me now.

A lot of people will tell you that you need a different fuel tank but this is not true. Just drop you tank, take the fuel pump out, unscrew the pump from it's bracket, take the feed tube on the bracket and attach a fuel hose (it must be a fuel hose) a little bit longer than necessary to reach the bottom of the tank. When reinserted, the tube will turn sideways when it hits bottom. Makes a good scoop. 2 years running with this setup.

As for the carb, I need to place a vote for the Holley. Some people are fanatical about their edelbrocks but the general consensus is that they are a bit harder to tune and a bit more exotic than holleys leading to less popular knowledge. Plus there's people selling dominators and deamon carbs on ebay for $100-150!!!

As for the extra parts....ebay them! I just made a couple 100 bucks selling off my excess parts in auctions! It's the bomb! You can even sell your old e7 heads and people buy them!

Well, anyway

Have fun!

~Crazy Pete