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-   -   Bolt on efi? (https://67-72chevytrucks.com/vboard/showthread.php?t=564361)

Samhecker 02-03-2013 07:30 PM

Bolt on efi?
 
I was just wonderin what kind of mpg gains i can expect from a bolt on efi like the one Holley or edlebrok makes by the way its goin on a 350
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Samhecker 02-03-2013 07:41 PM

Re: Bolt on efi?
 
Also if anyone can post a link to one preferabbley under 2000
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dieseldawg142 02-03-2013 10:57 PM

Re: Bolt on efi?
 
if your going holley or edelbrock, good luck under 2 grand. have an edelbrock pro-flo f.i. & it was right around $3500 all said & done. mileage in my case only went up maybe half a mile per gallon( 454, 38.5 swamps, 4:56's), but driveabilty is much better. no pumping, just reach in & turn the key(cold or hot) & no change or loss of power going threw the mountains. with a 350 i'm sure you could better my mileage gains

meatwagon83 02-03-2013 11:49 PM

Re: Bolt on efi?
 
i was thinking of getting the professional products one for my 454 (the one that looks like a carb) i have heard of milage gains and other positives, and i really havent heard anything bad about them

dieseldawg142 02-04-2013 12:09 AM

Re: Bolt on efi?
 
ya, throttle body is good, stock tb on my '90 stepper, 250k with 1 rebuild(easier than a carb). get about 17-20 mpg with mild 350, 5 spd, 4by, 3:73's

piecesparts 02-04-2013 12:16 AM

Re: Bolt on efi?
 
I have been watching a friend at the local Hot Rod Shop, in my area. He has a couple of the EZ-EFI setups from the FAST people mounted in a couple cars. One is a 61 Ford Stationwagon with a built up 390 engine and the other is a Duece Coupe with a 383 stroker engine. The learning curve on these direct bolt on setups, is that many require a "Clean" ignition spark from a good system like MSD. Otherwise the computer in the fuel injection is confused and does not produce well.

For the most part the fuel mileage gains was not that significant on his vehicles, but the overall power curve was enhanced greatly. I have a stroked 385 cubic inch engine in my 84 GMC truck, that I would like to gain some mileage on, as well as a larger performance area that a carb just does not offer. However, even with the lower cost that I could purchase the system from him at, the return may not outweigh the cost of getting the fuel pump and lines setup properly.

dieseldawg142 02-04-2013 01:05 AM

Re: Bolt on efi?
 
Quote:

Originally Posted by piecesparts (Post 5866127)
I have been watching a friend at the local Hot Rod Shop, in my area. He has a couple of the EZ-EFI setups from the FAST people mounted in a couple cars. One is a 61 Ford Stationwagon with a built up 390 engine and the other is a Duece Coupe with a 383 stroker engine. The learning curve on these direct bolt on setups, is that many require a "Clean" ignition spark from a good system like MSD. Otherwise the computer in the fuel injection is confused and does not produce well.

For the most part the fuel mileage gains was not that significant on his vehicles, but the overall power curve was enhanced greatly. I have a stroked 385 cubic inch engine in my 84 GMC truck, that I would like to gain some mileage on, as well as a larger performance area that a carb just does not offer. However, even with the lower cost that I could purchase the system from him at, the return may not outweigh the cost of getting the fuel pump and lines setup properly.

agreed, good spark is a must & it will enhance your curve & driveability. for a set up different than mine or if you plan on keeping the truck forever, i would absolutely go fi, otherwise no matter how you go about it, it's an expensive way to feed your motor, if fuel milage is your main concern

andrewmp6 02-04-2013 03:15 AM

Re: Bolt on efi?
 
Efi alone will get you so far you need a overdrive trans to really get better mileage.If it was me i would use the tbi these trucks got later on or tpi off a 3rd gen f body and a 700r4 and regear the rear end.If you want max mileage out the truck a diesel swap can break 20mpg easy but is costly to do.

dieseldawg142 02-04-2013 03:46 AM

Re: Bolt on efi?
 
Quote:

Originally Posted by andrewmp6 (Post 5866367)
Efi alone will get you so far you need a overdrive trans to really get better mileage.If it was me i would use the tbi these trucks got later on or tpi off a 3rd gen f body and a 700r4 and regear the rear end.If you want max mileage out the truck a diesel swap can break 20mpg easy but is costly to do.

absolutely! the pro-flo on my crew is feeding a 454 with t400 with 4:56's, hardly any diff in mileage, tbi on my stepper with od & 3:73's pullin almost 20mpg's. if you could find a good junkyard set up, i'd go tbi. cheap, reliable, easy to install/work on, but tpi is little bit more efficent, nicer eye candy too i think.

INSIDIOUS '86 02-04-2013 03:58 AM

Re: Bolt on efi?
 
I'm going tpi on my k5. From what I hear is you can hook an ls commuter to them and make them even better
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Samhecker 02-04-2013 06:38 PM

Re: Bolt on efi?
 
I got a 700r4 and 4 inch lift, do u think its worth it or should i look for another option. By the way i dont know what gears i have yet
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76stepsidechevy 02-04-2013 08:21 PM

Re: Bolt on efi?
 
Ive run an old holley pro-jection 2d and currently run a fast ez-efi setup. I didn't see any notable mileage increase with either unless you count fuel saved by not having to let the truck idle for 10 mins on cold mornings. It does run good though, good throttle response and the ez efi pretty much tunes itself after you give it a starting point.

dieseldawg142 02-04-2013 08:51 PM

Re: Bolt on efi?
 
Quote:

Originally Posted by Samhecker (Post 5867484)
I got a 700r4 and 4 inch lift, do u think its worth it or should i look for another option. By the way i dont know what gears i have yet
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the size of your tires & gear ratio would really help. your halfway there with a od tranny. the thing is do you want to spend big bucks for small gains? maybe a good tune & knowing what gears you have will net you some mileage. there's plenty of good threads for increasing your mpg's, but a lifted truck is not going to be challenging a smart car for fuel mileage anyways. in hindsight, i love how my motor is now with fi, but for the amount i drive it (2500 miles in last 3 yrs) i think i should have spent that $3500 on a coilover conversion

Samhecker 02-04-2013 11:13 PM

Re: Bolt on efi?
 
So a newbie question here, can i just swap a new intake and a tbi on my carburated engine or do i need to buy a whole new block
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85burb 02-04-2013 11:27 PM

Re: Bolt on efi?
 
I had a ez-efi from fast. It is a great product. I went from 7mpg with out of tune wrong size carb to 14 mpg with the ez-efi. It was on the 6.0 in my sig. It was 1900 shipped from summit cause they price matched the cheapest place i could find for the master kit. The only reason i sold it is to possibly go turbo/blower down the road on my burb.

dieseldawg142 02-05-2013 01:56 AM

Re: Bolt on efi?
 
wow! your carb must have been way out, thats a 50% increase in mpg's. i dont think that's representitve of gains you'd normally get switching to fi.

samhecker, you wont need a block. you will also need the harness, computer, distributor ( or convert your hei to hall) & you'll need to re-plumb your fuel system (elec. pump for fi & a return line)

andrewmp6 02-05-2013 03:34 AM

Re: Bolt on efi?
 
To use the truck tbi take a look at http://67-72chevytrucks.com/vboard/s...d.php?t=352321

piecesparts 02-05-2013 05:06 AM

Re: Bolt on efi?
 
Anyone hook up an EZ EFI to a truck with dual tanks? If so, how did you do it? As I stated earlier, I have considered the TBI setup and one of the issues is the fuel feed requirements. I think that the external fuel pump could be a problem in this deal.

dieseldawg142 02-05-2013 01:20 PM

Re: Bolt on efi?
 
i dont have EZ fi, (edelbrock fi), but i have dual tanks on my crew. i use an external Aeromotive fuel pump mounted upstream from the switching unit & you'll need a return line to each tank, other then that everything stays the same

Firebirdjones 02-05-2013 03:28 PM

Re: Bolt on efi?
 
Quote:

Originally Posted by dieseldawg142 (Post 5869123)
i dont have EZ fi, (edelbrock fi), but i have dual tanks on my crew. i use an external Aeromotive fuel pump mounted upstream from the switching unit & you'll need a return line to each tank, other then that everything stays the same

Yep, I run an external electric pump on my dual tank 79. Pump mounted in front of the switching unit. However mine already has factory return lines back to both tanks that works in conjunction with the switching unit, so it was a simple matter of just mounting the pump and running juice to it. Works fine.

MalibuSSwagon 02-05-2013 04:41 PM

Re: Bolt on efi?
 
Quote:

Originally Posted by INSIDIOUS '86 (Post 5866391)
I'm going tpi on my k5. From what I hear is you can hook an ls commuter to them and make them even better
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http://chevythunder.com/tpi_harness_upgrade.htm

I'm getting this setup for my TPI Malibu. Newer electronics, better software, newer and more plentiful parts. You can control a 4L60E transmission as well.

jimbonice 02-05-2013 11:30 PM

Re: Bolt on efi?
 
If your rig currently has a good running quadrajet, don't expect any mpg gains.

Having owned 454 and 460's, carbed, tbi and multiport, I've seen zero difference. The biggest gains I've seen is because of o\d trans. Fuel injection is not the panacea in full size trucks. If your economy sucks, spend $330 and buy a new carb.

Rich84 02-06-2013 09:15 AM

Re: Bolt on efi?
 
Quote:

Originally Posted by MalibuSSwagon (Post 5869474)
http://chevythunder.com/tpi_harness_upgrade.htm

I'm getting this setup for my TPI Malibu. Newer electronics, better software, newer and more plentiful parts. You can control a 4L60E transmission as well.

I wonder what you do if you already have a good 700r..What do you do to control lockup??
I sent him an email asking a couple of questions, but never heard back from him...Really interested in this upgrade as it seems the weak link in the tpi is the "buggy" computer. My understanding is that the tpi sensors work fine with the ls, it's the conectors that are different. I have a spare tpi harness. I wonder if I were to get a donor ls computer and harness and swap in the tpi connectors, along with the crank sensor etc...etc.. Just thinking out loud..

gchemist 02-06-2013 09:52 AM

Re: Bolt on efi?
 
Here is probably the most complete least expensive TBI available.
http://www.summitracing.com/parts/hly-502-20s/overview/

You keep your stock intake. A square flange adaptor bolts the TBI on a stock intake. It can support up to 275 HP.

MalibuSSwagon 02-06-2013 12:08 PM

Re: Bolt on efi?
 
Quote:

Originally Posted by Rich84 (Post 5871015)
I wonder what you do if you already have a good 700r..What do you do to control lockup??
I sent him an email asking a couple of questions, but never heard back from him...Really interested in this upgrade as it seems the weak link in the tpi is the "buggy" computer. My understanding is that the tpi sensors work fine with the ls, it's the conectors that are different. I have a spare tpi harness. I wonder if I were to get a donor ls computer and harness and swap in the tpi connectors, along with the crank sensor etc...etc.. Just thinking out loud..

Its very possible. 01-02 Express vans used the 12200411 LS computer to run a Vortec 350 with distributor, etc. So you would just use a Express van calibration, and all the Vortec parts. Seems easy enough.

Many of the LS sensors have not changed since the TPI days, such as the IAT, for example. Which simplifies the conversion even more.

As for wiring up a 700R4. I googled a bit and most people said the LS PCM cannot control the 700R4. You may want to look around a bit more.


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