EZ EFI or LS motor

[zcrz]

Hey guys,

trying to way the options of going Fast EFI on my 350 or going the LS route. I know everybody is loving the ls motors, but is it worth it? What am I really gaining that I wouldnt getting flipping to the EZ setup? The motor in it is 400 ish hp, just want better drivability and startup. This a weekend cruiser at best, I dont drive it much, but I will...just hate the stink and cold start up. Any opinions would be appreciated.

Thanks
ZCrz

[hifi875]

it will still stink w/efi. go ls you wont regret it

[Vegas69]

Unless you want to start over under the hood, efi it.

[6spdcamaro]

being that you already have the motor i would say update to efi. If you were starting with nothing the ls is probably better.

[64duece]

The LSx of the same power but do it with better overall driveability. IF you opt in for an all aluminum version, obviously it'll change the handling characteristics.

Your ahead of the game with respect to "having it already", although I'm abit preferential to a full multiport system with ignition control to gain the best advantage the EFI conversion would offer.

[Scatterbrained]

I am having this exact same issue. Although I was thinking about the Fast on a 383, versus having the LS motor. It seems like everyone is going the LS route, and with good reason, but I think I'm a little old school...

Scatter'd

[GregWeld]

Frank at Prodigy Customs -- look in the GROUP PURCHASE forum here - is running a group purchase on the NEW Fast EZ-EFI...

If you don't know what this is - check it out - because it sounds to me like you're the perfect candidate for a system like this. It's bolt on - replaces your carb - uses the same intake manifold - same linkage etc.... but gives you EFI and best of all - NO PRO DYNO or Pro tuning or laptop required.... It's answer some questions - fire it off... in an hour of driving it's supposed to be ready to go... and keeps tuning itself as you drive.

Worth looking at - because it's a day (or weekend) worth of wrenching -- and might solve your issues...

Just my .00000000000000005 worth.

[6spdcamaro]

I've talked to a rep from comp-cams (also fast) and he said the power difference from a single 4 barrel is non existent and on average they gained 3-6 mpg. It's cool because if you think the tuning is off you can adjust it yourself with the same control module you used to set it up.

[zcrz]

Yeah, i want to do the Ls, cause they are great motors (and everyone is doing them), just not sure on what I'm gaining over just doing the FAST install. I thought most of the stuff i've read shows a slight pickup on HP and TQ?

Thanks for the input!:lateral:

[GregWeld]

Well -- the real question is this --- DO YOU CARE WHAT IT COSTS?


Because if you don't care - and just want to be "late great" - then go for the LSx... because there's little doubt they're the killer motor... You'd save a little weight on the nose..

But - Big Butt - 400 Hp is 400 Hp and 400 Tq is 400 Tq -- while the curves might be flatter etc on the LSx -- it's still "equal" in most ways...

You're going to have to do A LOT of changing around to yank the SBC for the LSx... Radiator - fuel system - belts/pulleys - headers - blah blah blah --- so if $$ is no object - I'd be all over the LSx motor... BUT if you just want to make your motor "better" - "run better" - better milage etc - then just efi the SBC...

'Cause in the end -- it's only a budget decision. IMHO

[zcrz]

I know...its just I have a sh*t load of money in this car and hardly drive it for some reason....takes 10 minutes to warm up,wifey says its stinky, which it is and I just want to make it better to drive. I think this FAST setup may be what I'm looking for...money is always an issue for toys...:D

[94snglturbo]

do the ls motor.. im doing a ls2 motor. and i already had a badass 355 425hp fully custom motor. im doing the swap for drivability, reliability, gas mileage.. im also going to turbo the motor :)

[waynieZ]

I agree with Todd and Greg.
I was thinking of going with the Fast EZ but my motor makes 610 hp and that was at the top limit of the EZ, so I went with XFI set up. Now you can get over 600 with the EZ.
I thought of going LS but instead of changing some things I would need to change almost everything . My trans, clutch, headers just to name a few. Which I would have taken a beating on. If you have a good motor and drive train put the EZ and have a sweet running ride. I have a TBI on my 99 Tahoe and the throttle response is great and thats a 250 hp truck.

[GregWeld]

So.......... any decision on which way you're going??

[6D9]

I say EZ EFI . Lots of hidden costs for the LS swap that will nickel and dime ya. Dont get me wrong I would LOVE to have a built LS but my current combo runs killer and I would loss my butt trying to sell it. I may go for the same EZ EFI set up myself.

[zcrz]

Probably gonna try the EZ shortly. I havent been thinking about it much lately.

Any of you guys get the Fast setup installed yet?

[GregWeld]

I've got the ECM and harness -- and the Inglese 8 stack intake manifold - but it will be a week or so before the engine is on the dyno and I get to actually use the EZ EFI. :cheers:

[GregWeld]

Ran my new 406 on the dyno today -- with the new Inglese intake and my Imagine Injection throttle bodies - 36 lb injectors - and EZ EFI controller.

I can tell you that once I got all the throttle bodies sync'd up (there is some adjustment to make sure the blades are all set "equally").... in less than half an hour - the motor was making power pulls -- and every run got better and better - until each pull was exactly the same. The A/F's were right on the money - the exhaust temps were within 100 degrees of each on each cylinder - and the motor ran GREAT!

550 TQ @ 4600 rpms - 525.4 HP @ 5600 rpms

AMAZING STUFF I TELL YA! AMAZING... and I've been messin' with EFI for 10+ years now... this is so simple a friggin' caveman could do it!

And I'm talking a fairly big cam - with 8 stack EFI... :woot: :cheers:

[Vegas69]

Are you sure you didn't leave some top end hp on the table Greg? Peak torque at 4600 doesn't jive with peak hp at 5600.

[GregWeld]

It does - when you use baby heads on big cubic inches....

The Dart Pro 1 - 180cc heads are going to kill HP at higher rpms. But that was the way we planned the motor. It's a HOT ROD motor... I wanted big TQ down low in the band -- and was willing to toss the big bragging HP numbers in order to get there.

My Nomad weighs 4023 pounds - runs a 700r4 - and 3:70 gears... Tranny shifts about 5500 rpms... I have smallish tires in the rear. It burns rubber but won't set any 60' times! LOL

I wanted a "smoothish" running and torquey motor. The cubes and small heads (fast air flow) - give me the torque - but the small heads are going to kill the HP numbers. Here's something to look at:

RPMS TQ / HP

3286 478.3 / 299.3
4000 513.4 / 391.0
4600 550.0 / 481.7
4900 541.5 / 505.2
5100 527.6 / 512.3
5500 500.4 / 524.0
5900 455.4 / 511.6
6200 419.3 / 495.0

[GregWeld]

I would also expect the FAST EZ EFI to continue to tune itself and bring the A/F ratios in better and better. They are "set" in the programmer at 12.8 WOT - and the pull I posted above - shows 13.24 @ 4600 -- a little lean for torque production. This will tune itself as the ECU builds better VE tables. At 6000 rpms it was making 12.52 A/F

When Tom Nelson and I discussed this build - he said that the 8 stacks tend to add air so quickly - that it's hard for the fuel to catch up. I'm sure that having watched how quickly the ECM learned and adjusted from first start up to making some pulls -- that it will fatten the A/F as it learns more. But we felt - since the motor would run and behave differently as installed in the Nomad - rather than the dyno - there was little point in in continuing to flog the motor just to bring these to perfection.

The EZ EFI goes into learn mode as soon as the ECT hits 140* -- so every time you drive - it's honing in on the perfect A/F ratios...

[GregWeld]

Here's something else I was impressed with - and again - given the little amount of actual time to have the FAST EZ EFI learn...

Check out these EGT's

Starting with #1 @ 5000 RPM

1146 1045 1078 1050 1013 1087 1052 1090

[Vegas69]

It's definitely making some killer torque. It will be a great driver that will move that Nomad with ease. :thumbsup:

[BBC69Camaro]

Greg nice flat torque curve, seems like you had the same goal I did when I choose my setup :) Been thinking about EZ-EFI as well, thanks for sharing!

[GregWeld]

I just posted a new thread -- FAST EZ EFI under the EFI section

I'm 100% positively sold on this system -- PROVIDED you do your homework and supply some good vacuum signal for the MAP sensor etc. Super simple - super effective! :woot:

[BBC69Camaro]

Hey Greg, you do anything with your fuel system for the setup?

[Vegas69]

I just posted a new thread -- FAST EZ EFI under the EFI section

I'm 100% positively sold on this system -- PROVIDED you do your homework and supply some good vacuum signal for the MAP sensor etc. Super simple - super effective! :woot:

Cart>Horse:unibrow:

[GregWeld]

Hey Greg, you do anything with your fuel system for the setup?

No -- I already had EFI - so no changes - only change was the "rebuild" - intake - Computer.

This system does require a vacuum referenced fuel pressure regulator - and a return line just FYI.