what do fo you guys think of the Edelbrock Performer Multipoint EFI for our trucks?

[2LOW4ND]

what do you guys think of the Edelbrock Performer Multipoint EFI for our trucks?

http://www.jegs.com/webapp/wcs/store...45185_-1_10299

for 1987-95 Chevy/GMC truck and SUV 5.7L or 7.4L engines originally equipped with throttle body injection, these systems utilize the stock computer, sensors, and throttle body unit (without stock injectors) for an easy, effective multipoint conversion. Includes everything shown except a fuel pump (applications vary).

Stock Throttle Body Fuel Injection vs. Edelbrock Performer Multipoint EFI
TBI has two injectors above the throttle blades in the air valve; fuel spray hits the blades, does not stay suspended in the air stream, and results in uneven mixture distribution. Uneven distribution reduces fuel efficiency, horsepower, and torque for overall sluggish performance.

Performer Multipoint EFI has eight injectors that spray fuel directly into the cylinder head for ideal fuel distribution and efficiency. Only air is flowing through the manifold and when it combines with fuel at the intake ports, a high-velocity mixture packs the combustion chamber making the most out of every drop. The results are maximum performance, improved fuel economy, crisp throttle response, and broad torque curve for power where you drive the most.

Note: 50-state street legal via EO #D-215-43 on most 1987-95 Chevy/GMC truck/SUV with a 5.7L or 7.4L TBI-equipped engine or a factory replacement small block Vortec or 8.2L 502 engine

[Red94Chev]

Common question. Here is a good article on this kit: http://www.off-roadweb.com/tech/0310or_edel/. Edelbrock did their own testing using their performance parts (cam, heads, exhaust, etc.) and came up with about 270 hp. I use it, but I’ve matched it with Trick Flow heads and a cam from Comp Cams roller with more duration and higher lift. Engine output is around 385 hp according to engine dyno software simuations. Tuning your engine is the key to better performance. Here are the pro's and con's on this kit.

Pros:
1. I called Edelbrock and the supplied injectors are rated at 20.5#/hr at 43 psi. With tuning and maximal FP (~65 psi), these injectors are good up to 360 hp at 90% IDC. You can also swap the injectors for larger ones, so you'll never exceed the hp limit of the fuel injectors (particularly if you're thinking of adding a supercharger later or thinking about using a roller hydraulic cam setup with performance heads),
2. Least expensive manufactured multiport fuel injection system on the market that's brand new.
3. Single plane intake design that works well with high flow heads/camshaft upgrades. Although torque is lower than a dual plane setup at lower RPMs, torque output is still significantly more than stock.
4. There is an aftermarket adjustable FPR available for it. There are several manufacturers, including Holley, Jet, Automotive, etc. I purchased the Holley one (512-502) and switched the output connector with an AN-6 one (Barry Grant 140028). Easy peasy. There is a schrader valve for a fuel pressure gauge off the driver's side fuel rail. It can be swapped out to work with an inexpensive underhood Autometer fuel pressure gauge. In order to make this work, you'll need to exchange the position of the fuel rails (driver's side fuel rail to passenger's side and vice versa for passenger's side fuel rail) and rotate them 180 degrees (Edelbrock engraving towards manifold). The fuel lines hook-ups will still be at the back, but on the opposite side. You will also need to drill a hole in the throttle cable mounting bracket to easily access the AFPR with your allen key,
5. Better fuel economy through direct injection.

Cons:
1. Relatively expensive for the performance gain on stock setup
2. Some improvement in fuel economy, but not much (this is all relative of course because more power means less pedal on the highway going up hills),
3. You can achieve similar performance from a TBI/chip for less money BUT you'll need larger injectors to match your power output (about 290 hp at 90% IDC with 454 injectors - this is all with stock fuel pump of course. Higher fuel pressure will support more hp),
4. Need a custom chip if you use any camshaft or cylinder head other than Edelbrock. The Edelbrock tune is not optimal anyway, and probably explains the poor performance some people have experienced. You can save some money by ordering the 3502 kit, which is the same system w/o the Edelbrock-supplied chip. Under $1000. I think you can even download the 3501 .bin from the GMECM site and burn the chip yourself if you want. Otherwise, you'll need to find a qualified tuner who can work directly on the truck with a scan tool. Mail-order tunes IMO are a waste of money the more you've deviated away from the stock configuration,
5. Not a true PFI setup, since the PCM fires the injectors using the TBI firing strategy (twice as often as PFI). For a true conversion, you can use the PCM from a 93-95 truck ('7427/'8625) and convert it to PFI or get the EBL from DynamicEFI.com if you have an 87-92 TBI truck with the 1228747 ECM. Great upgrade in general for these older trucks.

This kit isn't for everyone and some would say it is cheaper to run TPI (and look cooler). I thought about that conversion too, but it has its own inherent problems as well (including poor flow over 4500 RPM). But for off-idle/low RPM torque using the stock heads, I don't think there is a better combination out there. It is becoming more difficult to find a donor setup with all the necessary parts. Even the scrap yards sell it for inflated prices. You can easily find one on ebay.

So to answer the question - is it worth it? On a mostly stock engine with stock heads - no. Even on a performance motor, I'm not sure if the added expense justifies the minimal performance gains relative to a TBI setup. TBI is capable of supporting engines with 360+ hp with FP/tuning/injector upgrades. Might have some issues at idle though. Most people would consider other performance upgrades first before attempting this swap.

[bthomas454]

no, it uses pico style injectors that cant be upgraded, dont do well with increased pressure, and arent all that reliable to begin with. fast305 and several other members here have had one, none of which had working eldelbrock setup something was always wrong on it.

[Red94Chev]

Originally Posted by bthomas454

no, it uses pico style injectors that cant be upgraded, dont do well with increased pressure, and arent all that reliable to begin with. fast305 and several other members here have had one, none of which had working eldelbrock setup something was always wrong on it.

The pico injectors are upgradeable and work just fine with increased pressure. I should know since I'm now running 29#/hr injectors and have run the original 20.5#/hr injectors at 65 psi with no problems. Any of the Edelbrock Pico injectors fit in the fuel rails. Edelbrock lists the part numbers as OEM replacement pieces for their Pro-Flo systems, but they are all interchangeable. Fast305 had talked about some idle issues and he had a hell of a time tuning it. It would be interesting to see how it would perform now that he has mastered the PFI setup with the '7427 PCM +/- MAF. The injectors are not the issue anyway with the system, but the price:performance detriment. For the average enthusiast, your money is better spent on a set of performance aluminum heads to replace the stock 083 ones along with a new camshaft.

[Blue71]

I've been running this setup for 2 years, only had 1 injector go bad (leaker).
Injector sizing jumps from 19# to 29# would have been better if they would have
offered some in the 24# range.

Running this setup with the supplied chip from Edelbrock on a stock engine might be ok,
But with any kind of head or cam change it will run like he!!

A modded PCM to run in PFI mode an AFPR is a must to get this setup to idle
and run with any modified engine.

It can be made to run, and very will i might add, with a little help from our friends here on the FSC.

[91chevZ71]

nice dual battery setup, blue.
FWIW
I called edelbrock and they said if you send the 19 pounders back without installing them they'll send you whatever size injectors you need for 40 bucks (shipping/handling).
The 29's are pretty big... like running 4 TBI 350 injectors. that's a lotta fuel

[Red94Chev]

Originally Posted by 91chevZ71

nice dual battery setup, blue.
FWIW
I called edelbrock and they said if you send the 19 pounders back without installing them they'll send you whatever size injectors you need for 40 bucks (shipping/handling).
The 29's are pretty big... like running 4 TBI 350 injectors. that's a lotta fuel

Depends on the output of your engine. When choosing injectors, you want the injectors running at 80-85% duty cycle for accurately metered flow and some wiggle room. Therefore, these injectors would support 372-394 hp. My engine combo has a power level around 385 hp. The PCM adjusts the injector pulsewidth to supply the right amount of fuel. PFI would correct the idle problem with this system.

Add the AFPR like I detailed in my post above and increase the FP to 60-65 psi. This is equivalent to 24#/hr injectors. Make sure to change the injector constant in the PCM for the higher flow.

[seaeagle2]

You're lucky, ususally the feed back you get on this set up is from people who haven't actually got one and have run it. Here's my version, I picked up a used setup on Craig's list for 350, I had to buy a fuel pump and the fuel lines and hose ends. I installed it myself, and once I figured out the timing was off, it ran. for a non gear head, I figure anytime you can pull the manifold off, install a new one and get it to run, I'm doing okay. I did take mine in and get a dyno tune from a place edelbrock refered me to. For what I've got into my set up I figure I paid what I would have for a tbi manifold, new throttle body afpr, etc. and I'm happy with the performance gain I got. I don't know that I'd feel the same if I had bought everything brand new. And I have everything stock except for heated oxy sensor, headers and cai. I'm going to do different heads and cam one of these days based on what the tuner has done for other guys in the past http:////www.fquick.com/images/vehic...jpg?1200091135http:////www.fquick.com/images/vehic...jpg?1200091135

[91chevZ71]

Originally Posted by Red94Chev

Depends on the output of your engine.

yah, I was just saying. pretty healthy engines need that kind of fuel. hence the 19# inj's stock with the system.
totally agree with ya on what you're saying about duty cycle, AFPR's, inj flow rating and chip tuning.

[2LOW4ND]

So basically for the money spent, alot of you guys like the setup. But could justify running better heads and a cam insted of spending money on the fuel system?

[91chevZ71]

Important to note that this setup seems to be worth it only when you can tune it yourself, I think.
Cheaper to go with a suped-up TBI setup, though. Nice to have port fuel, though. I could do this all day...lol
Wonder if the edelbrock MPFI manifold has more volume than the TBI manifold.
I don't see why you could get 400 HP out of the Edel MPFI (with the correct parts, of course). 400 HP TBI is possible too.
Whatever appeals to you

[2LOW4ND]

Well my goal with the motor is to try to keep the original motor and keep it clean. I want a snotty motor, nothing to crazy just some stout power. I have built a couple motors from the block up with carb motors. one for my 72 GTO and one for my good ole v-8 swap in my S-10.. So lets say if i dont run this fuel system but do run a high pressure intake fuel pump fuel reg larger injectors, cam and lifters, already have headers and a decent exhuast, it might be a clean setup to get the 350 to come to life a little bit... ??

sidenote, i dont wanna break the bank on the motor right now. Im in the process of finishing up the bag setup etc and just wanna get a little more out of the motor.

Originally Posted by 91chevZ71

Important to note that this setup seems to be worth it only when you can tune it yourself, I think.
Cheaper to go with a suped-up TBI setup, though. Nice to have port fuel, though. I could do this all day...lol
Wonder if the edelbrock MPFI manifold has more volume than the TBI manifold.
I don't see why you could get 400 HP out of the Edel MPFI (with the correct parts, of course). 400 HP TBI is possible too.
Whatever appeals to you

[oldred95]

Its deffinitely a slick setup but you could also build one and at some point I intend to. Seems like it would be fun to build it too. I like bending tubing, fabbing crap like that and the like.


This place has some injectors that could probably feed the need up to a few thousand horsepower.

http://members.aol.com/bigturbo1/fuel1.html

[Fast305]

The trouble I always had from day one with the Edelbrock setup, NIB was the PICO style fuel injectors. From day one they acted up. I think I replaced a total of 5 injectors in a 6 month period. They would either leak or stick closed, causing a miss either way.

[Roril]

Interesting post. I too was going for a Edelbrock Performer Multipoint EFI but have now decided to go with a new cam, ED 2162, TBI Bored out to 750 cfm from www.rvmorsemachine.com, spacer, MSD coil and TBIchips. Already have the new ED Headers, K&N filter and Gibson 3" catback installed. My goal is to have my "heavy Chevy" be street worthy, run on 87 oct and not kill the mileage.

1995 Silverado Crewcab Longbed, 7.4l Victory Red 74 with matching SnugTop.

[91chevZ71]

Any technical reason WHY edelbrock used the pico inj's?
With all the issues with those things I see how it was 'smart' for edelbrock to use them...

[seaeagle2]

Aren't they made by the company that makes Edelbrock Carbs, I think that's why they use them.

[Blue71]

Originally Posted by seaeagle2

Aren't they made by the company that makes Edelbrock Carbs, I think that's why they use them.

Not 100% sure, But I think they are made by Magneti-Marelli
they use the PICO (smaller size) injectors to place the injectors more in line for a direct shot to the back side of the intake valves

[91chevZ71]

Originally Posted by Blue71

place the injectors more in line for a direct shot to the back side of the intake valves

interesting. I take it the LT1/TPI injectors don't do this as well as the pico inj's

[Blue71]

Originally Posted by 91chevZ71

interesting. I take it the LT1/TPI injectors don't do this as well as the pico inj's

I don't think it would have any thing to do with what type or make of injectors you using.
More on the lines of how the fuel gets into the intake port.

looks to me like Edelbrock ran out of room for the fuel rails by putting the injectors at this angle.
does it make it run any better