Options If I Can't Run a MAF

[terpngator]

OK guys, I'm really struggling here trying to get plumbing set up to run a MAF on my 96 LT going into my 1939 Checy project. These cars 'pinch' really hard in the front making cooling and air intake plumbing VERY challenging. So what are my options if I can't run a MAF in my hot rod?

[fbody_Brian]

OK guys, I'm really struggling here trying to get plumbing set up to run a MAF on my 96 LT going into my 1939 Checy project. These cars 'pinch' really hard in the front making cooling and air intake plumbing VERY challenging. So what are my options if I can't run a MAF in my hot rod?
Tune it for speed density.
I believe that without a maf that's your only option.

[fbody_Brian]

That intake elbow looks like it may stick out farther than the ones on a fbody. Have you tried an fbody intake elbow?
Of course there may still be too little room for a maf.

[EDZIP]

Recently installed an LT1 in my son's 37 Chevy. Made my own motor mounts so the engine would set lower and back further. Still lacked room for a pull fan..so we installed the biggest pusher fan made by Derale 17" (2) speed.

We wanted to keep the MAF setup so just put together an elbow setup...looks great in person and he hooked up LED's that really light it up at night.

BTW: Check out my forum at: www.RustyBowtie.com

Ed

[Six_Shooter]

I was going to suggest the solution that EDZIP has shown. There's a car locally where the same solution was used and he has been driving that car for a number of years that way.

[terpngator]

Recently installed an LT1 in my son's 37 Chevy. Made my own motor mounts so the engine would set lower and back further. Still lacked room for a pull fan..so we installed the biggest pusher fan made by Derale 17" (2) speed.

We wanted to keep the MAF setup so just put together an elbow setup...looks great in person and he hooked up LED's that really light it up at night.

BTW: Check out my forum at: www.RustyBowtie.com (http://www.RustyBowtie.com)

Ed

Thanks Ed. Yeah, that's the route I'm heading in. (see pics) I'm using a Flex-Lite 2700 CFM dual speed fan. My issue is the hood is hitting the sides of the radiator tank. Looks like I'm going to have to move the radiator back about 2" to get it to clear. As you can see, I have VERY little room.

I'm determined to use this LT engine. Caught a LOT of guff from fellows in the club dogging this engine. It runs strong. Any tips you can impart, I'm all ears.

[EDZIP]

If you need a source for a silicone elbow and aluminum pipe, I can ask my son where he bought it. We have the opti vacuum line and air temp sensor mounted after the elbow. Runs strong and sounds really great.

I bought one of those Rand aluminum radiators on eBay...usually under $150...I have one in my 33 Chevy and a couple of buddies use them also..work great. The Rand radiator fits the radiator support nicely and clears the hood...I suspect it drops down further than yours.

My son drove the car this summer without a temp problem...next year we may drop in a 180 thermostat and drop the fan kick on speeds to match. Installed fan by-pass switches just in case...but never had to use them. I'm just not used to cars running 220(+) degrees and that being normal.

[Six_Shooter]

You need to get away from that bend you're trying to use. Most off the shelf aluminum bends will be too wide of a radious to do what you want. You might have to make a custom box/plenum that makes a tighter bend around.

[terpngator]

You need to get away from that bend you're trying to use. Most off the shelf aluminum bends will be too wide of a radious to do what you want. You might have to make a custom box/plenum that makes a tighter bend around.
No doubt ur right Shooter. I've looked at every elbow available and all have about the same radius. I searched the local U-Pull yards for something else with no joy. I could probably make a box style connection from HVAC sheet metal.

[steveo]

honestly after spending many hundreds of hours tuning LT1s in every way possible; i will tell you that just ditching the maf is WAY better. simpler plumbing, less wiring, less failure prone, and it seems, from a seat of the pants difference, better transitional fueling too, probably due to the fact that the lt1 maf is an antiquated design? a good speed density tune always feels a bit 'snappier' to me.

it's all at the expense of a bit extra tuning time, but you're on a tuning site, so lets assume the idea of spending some time tuning doesn't bother you too much.

[terpngator]

honestly after spending many hundreds of hours tuning LT1s in every way possible; i will tell you that just ditching the maf is WAY better. simpler plumbing, less wiring, less failure prone, and it seems, from a seat of the pants difference, better transitional fueling too, probably due to the fact that the lt1 maf is an antiquated design? a good speed density tune always feels a bit 'snappier' to me.

it's all at the expense of a bit extra tuning time, but you're on a tuning site, so lets assume the idea of spending some time tuning doesn't bother you too much.

Hey Steve, I really don't mind the tuning, in fact I enjoy trying to get the most out of this engine with the tune. You did the initial tune for me over a year ago when I first installed the engine in the chassis. I'm the one that sent you the spare ECM for your help. I still have not driven the car, issues with getting the body done and painted. So once I take the MAF off, what do I have to do with my tune? Here is my engine:
ENGINE

5.7 Gen II LT1, bored .030 to 355. Block decked to .015. aprox 11.5 to 1 comp.

HEADS:
CASTING # 1020764, 54CC COMBUSTION CHAMBERS
10128374 = Gen.II LT1, 54cc, angle plug, aluminum, reverse flow cooling, 175/68cc port volume
Valves: 2.02 Intake 1.60 Exhaust
Runners smoothed and matched to intake.
32 Lb/hr Bosch Injectors (http://shop.ebay.com/?_from=R40&_trksid=p5197.m570.l1313&_nkw=bosch%20injectors)

CAM:
Cam Style: Hydraulic roller tappet
Basic Operating RPM Range: Idle-6,000
Valve Springs: LT4 Hot Cam springs
Intake Valve Lift: Int/Exh .525/.525
Duration: Int/Exh 218/228
Lobe Separation (degrees): 112

TRANSMISSION:
4L60E Rebuilt with Sonnax Performance Pack HP-4L60E-01 Kit. Billet pinless accumulator pistons.
Sonnax 1-2 and 4th Super Hold Servos.
VSS IS connected to ECM

REAR:
Ford 8.8 from 2000 Explorer. 3.55 gears.

SENSORS:
MAF—Hooked up
MAP—Hooked up
TPS—Hooked up
IAC—Hooked up02 sensors—2 installed
ECT (engine coolant temp)—Hooked up
IAT (intake air temp) connected in intake ducting.

CPS (crankshaft position) not hooked up

[steveo]

Hey Steve, I really don't mind the tuning, in fact I enjoy trying to get the most out of this engine with the tune. You did the initial tune for me over a year ago when I first installed the engine in the chassis.

it was you! thanks for that ECM, i basically wrote eehack with it; it's been a great help.


So once I take the MAF off, what do I have to do with my tune?

you learn to tune speed density... which just involves re-shaping the VE table. that table represents how much juice it needs for any particular RPM to meet its target. (actually it represents airflow, just like the maf table, but it's better to think of it in terms of adding/removing fuel) luckily there are tools for tuning them, and i wrote a really easy-to-use one built into eehack.

make yourself a tune with the MAF sensor and its associated error codes disabled, and power enrichment disabled. you'll want power enrichment disabled just so you can drive it at higher RPMs and still get useable data. make double sure your constants like injector size are alright, that'll speed stuff up a lot.

i'd also change blm cell boundaries to something like (rpm)1000/1800/2500 and (map)45/55/65 just to enhance its learning ability a bit.

bring a laptop or something with you, run my eehack program to log data, and start driving the thing.

it'll probably run alright once it warms up, but it'll be a bit jumpy and stuttery in some operating ranges. it'll slowly get better as you drive, but not great.

try to drive in a variety of conditions.. loaded cruising, lug it, cruise at high rpm, low rpm, do some manual shifting, just don't hammer on it too hard since power enrichment is disabled, and it could be a bit lean..

save your logs to disk somewhere, and keep driving till you have at least half an hour of driving data (more is better)

then you load all of your logs at once, and run the cruising afr analysis. the default settings are pretty good.

you might have to click 'factor int into calculations' and decrease your cell count a bit if you want to tune areas that you were scared to drive in for more than a second or two, but that makes all your data less accurate, so i'd do that after tuning the important parts. the nice thing is, the most common driving ranges will naturally be the ones with the most data, so they'll end up being more accurate.

now that you have a nice map of changes that need to be made to various parts of your VE table; you just display the VE table in tunerpro, and start hand-tuning it.

best way to do it is select regions and scale them by a percentage, you'll start to see your new ve table emerge as a series of spikes and cliffs that you just have to smooth out the best you can. the reason you'll do it by hand is that you wont have data for a lot of your table, you have to look at it and 'fill in the blanks' yourself.

hopefully once you start making some changes, you'll be able to visualize what the missing parts of your data are supposed to look like.. using tunerpro to tune your VE table, you can overlay your old table to see how dramatic the changes you're making are, visually. when in doubt, a tiny bit more fuel will be better than a tiny bit less.

after you've tuned it, do the whole thing over again. it'll take at least a few 'passes' to nail it. good tuners can usually do it in a couple passes, you might be spending your entire life on it for a few years, who knows.

[steveo]

oh yeah.. after that you just re-enable power enrichment, maybe dial that in a bit, and you're good to go..except for spark tables, but eehack can do most of the work for you there, too.

[EDZIP]

Terpngator... just curious..96 engine...which PCM are you using?

[lionelhutz]

Look for a reducing silicone elbow to get a tighter bend. I think 4" would fit on the throttle body. Well, you have a reducing coupler on that cast elbow so you likely know the size.

A site like intakehoses.com should have what you need.

And get rid of that corrugated flex hose to the filter.

[steveo]

Terpngator... just curious..96 engine...which PCM are you using?

see old thread;

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?3641-Old-mechanic-looking-at-learning-new-skills

[EDZIP]

No doubt ur right Shooter. I've looked at every elbow available and all have about the same radius. I searched the local U-Pull yards for something else with no joy. I could probably make a box style connection from HVAC sheet metal.


FYI: the silicone elbow that my son picked up fits the throttle body perfectly and transitions to the 3.5 aluminum tubing that then fits the MAF perfectly. I doubt any air flow concern...the car runs and performs great.

[lionelhutz]

FYI: the silicone elbow that my son picked up fits the throttle body perfectly and transitions to the 3.5 aluminum tubing that then fits the MAF perfectly. I doubt any air flow concern...the car runs and performs great.

I believe it is 4" on the throttle body to 3.5" for the ducting.

The site I tried to post didn't give a link so it might get overlooked and I just remembered another one.
www.intakehoses.com
(http://www.intakehoses.com)www.siliconeintakes.com


(http://www.siliconeintakes.com/)

[EDZIP]

Pretty sure this is the one we used....

http://www.siliconeintakes.com/bending-reducer/reducer-elbow-p-147.html

The aluminum tubing a T bolt clamps are on their site also.

[lionelhutz]

You're probably right Ed. I couldn't recall if it's 4" or 4.5" but the right size elbow like that will deform and fit the oval shaped throttle body just fine. And, an elbow like that will make the bend a lot shorter than using a straight coupler and an aluminum elbow.

[EDZIP]

Here is another early picture