Has anyone had experience with the Edelbrock multi-port fuel injection setup for TBI? I've been seriously considering this for my 350. It uses the existing computer, existing TB for air only and squirts fuel direcly into each cumbustion chamber just like regular MPFI. Edelbrock says they gain 25hp just by switching to this setup from standard TBI.

I have a 670cfm TBI, so I would think that would be plenty of airflow for 350hp or so. The fuel supply would be no problem either. I also have Edelbrock's 6085 heads which will make it a matched setup.

What do you guys think? BTW, it's only $900 including 8-injectors! It would still be considered TBI, right?

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'92 RS, ZZ4 10:1 350, Edelbrock 6085 heads, Crane 208/214 467/482 cam, GM/LT4 1.6 true roller rockers, Holley Projection TBI intake, Holley 670 TBI, SLP/Jet-Hot 1-5/8" headers, Catco 3" cat, Flowmaster 3" catback, Hughes 2500 stall converter, stock 700R4, Auburn Pro posi w/3.42, 17x9" SS rims w/BFG tires, Medium Quasar Blue w/white SS stripes, 48,000 miles....

 

No, it would be considered multi-port fuel injection. Throttle body injection means injecting the fuel at the the TB. Port injection means injecting the fuel at the intake ports.

If you are gonna go with port injection, then pick up the 90-92 harness and ECM 1227730. Just MHO. You *may* be able to do the above for less than $900.

 

Only one I know of uses the 747. Which really isn't designed for TPI, and you wind up with a rather mismatch of parts.
That and they really didn't look to get to clever in the chip to run it.
Take the 900 and go with a late MAP system.
Or get the Ebroke system and then wire it up for the 1227730 ecm.

 

I have a friend who has a brand new GM '92 TPI harness, so that's easy, but what about this 1227730 ecm? Why would the Edelbrock system not work with the ecm it was designed for ('90-'92)?

And I've priced the alternative:

TPI Harness $250
Injectors $400
Big Mouth $500
Runners $300
Plenum $200
52mm TB $350
Fuel rail $ 50
Fuel pump $100
Custom chip $350

Total: $2500!

I figure I can do the Edelbrock MPFI complete for far less than 1/2 the price, so where's the disadvantage?

 

I think Howel engineering tweak the edelbrock setupt to use the TPI or some other computer. whatever they do its supposed to be better an I think they add $500 or $600 to the edelbrock $900. so $1500 or so. Honestly I don't like the idea of the small injectors. Check out the holley stuff on my EFI page.

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-Tas
'89 Formula WS-6
[soon to be Performace Red =) ]

305, TBI, auto, 14x3 chrome flat based open element with K&N, functional Formula hood, cross-flow Flowmaster, '99z28 rear pipes and tips....

Super GRK_Taz World
EFI & Intake Options
AOL IM: superGRtaz
ICQ 82881207

 

ummmmm ok 25 hp?? r u seriously telling me that 25hp is worth 900$?? Well not to me. I think for 900 u should get some gears and port and polish ur heads for that. I bet the increase between the 2 would incredable.

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1989 pontiac firebird
bright red exterior(just repainted)
grey interior
5 spd
305 TBI (stock)
WS.6 formula wheels
3.73 posi rear end
-------------------------
system: 2 10" MTX thunder 2000 in a Professionally done custom bandpass box.
Blaupunkt CD player
Blaupunkt 4x6 and 6x9
600 watt rockford fosgate 4.6 amp

http://members.aol.com/j007golden/Mikey89.html

 

lol im sorry i didnt see ur sig, maybe it might be worth more for ur set up

 

Exactly...Edelbrock gained 25hp over a stock TBI setup on a stock engine. In other words, they added nothing but MPFI and gained 25hp. Add a bigger TB, heads, cam, rockers, etc...and it should make an even bigger difference.

I'm just looking to find a good but not rediculously expensive MPFI setup for my 350. Since I already have a 670TB, I thought the Edelbrock might be a good idea.

I've looked at the Holley stuff too. I'd actually prefer the complete Holley 1000cfm setup, but it's like $2500! I just can't see spending that much on simple fuel injection. And the $255 MPFI intake would still require the injectors, harness, fuel rail, pump, chip, etc., so it would not be cheap either.

[This message has been edited by Scott C (edited November 26, 2000).]

 

$2500 is for a system capable of 500 HP easy, you'll never see that with the $1200 setup.

For a stock TPI to match the same HP level as the Edelbrock
$50 for the harness (I've bought 4 at this price, takes shopping)
$50 for the ecm (bought dozens for this)
$200 for the software and burner
$250 for an oem intake complete (have bought and sold a few for this)
$109 for a real fuel pump (for a 600 HP walbro 340 is fine)

To get you edelbrock really right will also take the $200 for software etc.

 

.

[This message has been edited by Pablo (edited November 26, 2000).]

 

They added a little more than just mpfi, if you really wanted you could add mpfi to your stock intake and REALLY do a comparison of MPFI vs tbi instead of this foolishness of conning people into thinking that there is such a huge difference between TBI and MPFI when you changed a huge part of the intake tract (intake manifold) and added "performance" programming and who knows what else (aicleaner?) etc

I think thats borderline false advertising (implying that the MPFI made all the difference)

 

I think the difference is mainly the 6 additional injectors at the optimum locations. Droplets of fuel trying to make their way to 8 separate combustion chambers has to be far less efficient than a spray of fuel shooting right at the intake valve, right?

I was just reading a past issue of GMHTP where they reviewed the Holley Projection II MPI with 1000cfm TB. They claimed 50rwhp by just adding the MPI and the software. That setup is about $2500.

Oh well, I'm still searching for the best way to fuel my new 350. I'm just looking for a mild setup to give me 350hp or so. I'm sure my current TBI setup could get me there, but at it's peak level. MPFI is very happy all the way through 500hp+, so it's a cake walk to produce 350hp.



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'92 RS, ZZ4 10:1 350, Edelbrock 6085 heads, Crane 208/214 467/482 cam, GM/LT4 1.6 true roller rockers, Holley Projection TBI intake, Holley 670 TBI, SLP/Jet-Hot 1-5/8" headers, Catco 3" cat, Flowmaster 3" catback, Hughes 2500 stall converter, stock 700R4, Auburn Pro posi w/3.42, 17x9" SS rims w/BFG tires, Medium Quasar Blue w/white SS stripes, 48,000 miles....

 

I think the difference is marginal in terms of peak power production

The only things i see mpfi doing better at are #1 big airflow changes, like shifting gears, which i think would cause some fuel drop out in a wet flow manifold

which is no doubt better for track times but im just hypothesizing

#2, the idea that 8 injectors are better isnt neccessarily true when you consider that all injectors have a variance, and every port of the heads sees varying amounts of air just due to runner design and whatnot, for example, an edelbrock performer manifold sees something like a max of 9% variance among the runners cfm wise in airflow. Consider that even if you had a perfectly balanced set of injectors, they will be shooting the same amount of fuel into the cyl with the highest airflow as the one with the least

even if you could see what each individual cyl was doing, youd have to drop some coin on a vic or sfi to correct it and that would be still more tuning since airflow through a port isnt neccessarily linear to engine speed, that varies too

a wetflow manifold you could say feeds the cyls on demand which would be advantageous, of course, no system is perfect so there are losses in the wet flow system as well such as fuel puddling as it hits the manifold floor, or drop out on rapid throttle opening or engine speed transitions.

As with any system, these things are known and there are all sorts of things you can do to minimize them... all problems that is, with any system.. so in the end, a properly designed system vs another properly designed system isnt really all that cut and dry in terms of performance, for example on the top end a carburetor can actually atomize better than the current crop of injectors on the market however since injection holds atomization to more of a constant than does carburetioin you frequently see better low end torque numbers from FI setups and many times better top end from carbureted setups.. just my theory on that


Theres no doubt that port injection is better.. but just how much better to make it worth a grand? in theory you could probably tune for better fuel mileage, better throttle response, better transitions like gear shifts

you COULD tune for it, the same way someone could tune a wet flow system for it, everything can be optimized to where someone who was cuckoo could setup any one of those to make incredible power with minimal losses

thats my 2 cents, take it or leave it


Grumpy knows his stuff about this hopefully he will have some comment on it all

 

also consider that batch fire systems are firing on a closed valve most of the time at WOT.. not that its a huge issue ive seen dyno tests to where the difference between sfi and bfi was like 7 hp on a 650 hp motor (that was in GMHTP)

 

With the proper PROM work and cam/head/exhaust combo, the edelbrock system is EASILY capable of 300hp! I guess that's not tons, but that is with a really mellow CR (less than 9:1) and a really mellow cam (204/214 ish) so it is VERY drivable and will pass emmissions easily.

With bigger injectors other motor/PROM/exhaust work, you should be able to get 400+ hp out of it. Just depends how much you want to spend and how capable you are.

 

You need to have a goal in mind.
There are lots of issues, if you want a well mannered 325/ 350 wither TBI ot TPI will do it just fine.

HP is about burning fuel.
You have two ways in which to make it burnable, atomization, and vaporization.

And you have two areas of concern. Low speed and high speed.

At low speed the TBIs use atomization, ie notice how well spacing the injectors up can help. Then at higher speeds when you lose the shearing effect of the butterfly you need to have vaporization come to your aid, notice how involved the runner heating is with the coolant.

On a TPI while there is some atomization, the injector is usually blowing the fuel against a closed intake valve (BTW, the backside temp of the intakes is in the neighbor hood of 600dF. So that does an excellent job of vaporizing the fuel, even in SEFI GM blows the fuel at a closed valve.

The oem bummer with the TBIs is that the XFire was the only one to use a single plane. While the XFires can be made to run well the mags were so fast to make fun of them, that the dumb being lead by the dumber just repeated that long enough that it become a popular opinion based on ignorance.

TBI suffers from the same advantages and disadvantages as any wet fuel manifold. You just have to make it work for your APPLICATION.

TPI has fewer inherit faults, but executed poorly is no worse or better then anything else.

Bottom line to all this?.
Establish exactly what you want to do, and then optimise for that...
Just for grins, look at this URL.
I want a sedan to *haul* 4 adults, hehehehe
Grumpy
http://www.gnttype.org/carofthemonth...omdetails.html

 

I'm beginning to see the light! Sure, any form of MPFI has it's advantages, but like others said: "is it worth a grand?" or more?

I'll give my current TBI setup a try with an Ed Wright chip. If I'm not happy, then I'll look to MPFI. If I do wind up with MPFI, then I'd probably choose a TPIS BigMouth base, large tube runners, 52mm TB, ported plenum and other goodies.

All this indecision and I haven't even cranked the new engine for the first time!! Guess I should see how she does before I go changing everything.

Thanks for your input, guys...




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'92 RS, ZZ4 10:1 350, Edelbrock 6085 heads, Crane 208/214 467/482 cam, GM/LT4 1.6 true roller rockers, Holley Projection TBI intake, Holley 670 TBI, SLP/Jet-Hot 1-5/8" headers, Catco 3" cat, Flowmaster 3" catback, Hughes 2500 stall converter, stock 700R4, Auburn Pro posi w/3.42, 17x9" SS rims w/BFG tires, Medium Quasar Blue w/white SS stripes, 48,000 miles....

 

I priced the Weiand/Holley new stuff to make a MFPI and use TBI computer (kinda like ghoSST/Eelbrock conversion systems) and it was about $1200ish with:

Manifold = $255
rails/reg/fitt = $188
Injectors = $400 (ish)
Fuel Pump = $110
Bungs, if needed, = $77
TBI adapter-to-manifold = $45-65
Harness for injectors (Howell???) $30-60

My above prices are a lot if the Howell kit has all the above (less fuel pump) for only $750...

ghoSST, what parts EXACTLY do you get from Howell for only $750??? They will get my business if it is that much better than my prices and is for NEW equipment...

 

I know for a fact that the harness from Edelbrock is 43.24. I called and told them that I had lost the one from my kit and they sent me to their sales department. AAMOF, the PN is 37-0502

Here is the exact email that I recieved from Troy at Howell:

I emailed them last night and spoke briefly
with Troy today. When you look at it, the
injectors, fuel pump, fuel rails and intake are the only costly parts on the Edelbrock conversion. All the rest of it is mostly nit picky crap. If they're picking up cheaper injectors, supplying all the little stuff, then I imagine that it would be possible for them to make a little money off of the whole deal.

Kelly 'GhoSSt' Rosato

 

Well, lets look at this from a sales point of view.

Manifold in bulk from Edelbrock - 150
Fuel Rails - 150
Injectors (SVO 24's) - 210
Fuel Pump - 90.00
Hose, fittings, bolts, crap - 20.00
Harness at Howell's cost - 10.00
1 prom chip - 5.00
No bungs needed
No Carb to TBI adapter
-
I see about 630 or so, their cost. Thoughts?

Kelly 'GhoSSt' Rosato

 

Well, its official, I ordered my Howell/Edelbrock multiport kit today. With shipping it was 775 and change. I'll let you know what comes with it and whether its a viable upgrade or not. Comes (as I suspected) Howell 19lbs injectors and splice in harness. So we'll see.

Kelly 'GhoSSt' Rosato

 

Great. I'd like to see what you get and how the assembled quality is.


I guess those 19lb injectors could support up to 300hp, right??? I have some 28lb'ers but I bet they won't go right into the Edelbrock *** 'y. Are all TPI/MPFI injectors of the same height/o-ring diameter/etc??? ie, are they interchangeable???

 

19lbs is pretty weak! Well, it's stock for a 305 TPI, but what if you want more power in the future? Do you spend another $200-$400 for new injectors? Does Howell have an option for larger injectors?

I'm very interested in the details! Keep us posted on Howell's service, products and knowledge. I've heard they've slipped quite a bit since the original TBI guru passed away. I have not dealt with them in about 5 years, and they were only so-so then.

 

I'm not sure. Remember, I'm coverting to MPFI first, then once I get that up and running, I have about 3 weeks before I pay off the LT4 (bad cam lobe) and a couple of weeks after that to get the LT4 BACK IN the Impala. So I'm about 6 to 8 weeks out from the 406 install, but I need the Caprice to run during that time period. So after I do the MPFI swap, I'll pay off and install the LT4 383, then install that, then do my engine swap in the Caprice to the 406. Once I do that, I'll swap to 30lb Bosch injectors then. So basically the 19's with the chip they;re sending should keep the 350 happy for now.

Quote:

I'm very interested in the details! Keep us posted on Howell's service, products and knowledge. I've heard they've slipped quite a bit since the original TBI guru passed away. I have not dealt with them in about 5 years, and they were only so-so then.

Yeah, I'm hoping. What I'd like to do is see if the product is something that we could replicate with a little effort and cut out the middle man (men).

Hope that made sense...

Kelly Rosato




[This message has been edited by GhoSSt (edited November 30, 2000).]