Supercharged Flathead EFI, Megasquirt

Zack, I was going to do the same thing, but minus the blower. MegaSquirt is the best solution in my mind, and what is more cool than tuning a 70 year old car with your laptop!!! You did a great job.

One question: What did you use for a throttle position sensor? That was my dilemma.

 

you can also do it with a palm pilot or other PDA....

 

I am getting ready to put MS on my 200 inliner. intake is cast with head so welding in some injector bungs into the head. it is going to be ran off a stock duraspark dizzy with locked out timing. future plans are a ford EDIS setup and a soon to be released Alloy race head (heads are currently in production first batch due in OCTOBER!!!)

 

For forced induction you just use a MAP vs. RPM based fuel map. A thottle is just a pressure regulator if you think about it. You can use a thottle position sensor for acceleration compensation and that will go a long way to help throttle response with a MAP based map. We run our N/A Formula SAE cars MAP based with no TPS... and it works alright.

 

Hey man, anybody that can put together a megasquirt system like you did and make it work, you're a better man than me. Congrats! It looks great!

 

It's nice to see a lot of good questions, but even better is I've got answers for all of them.

As has been said, the injectors are above the blower both because of clearance issues below the blower plate and port geometry. When starting I took a few rough mesurments for port injection and ran into problems getting the fuel rail under the blower. The angle required would put the injectors facing INTO the flow, the effects of which I can't really speculate. The big problem with them being above the blower is pretty severe wall wetting which isn't a problem at all when increasing manifold pressure (when it counts) or at steady state. It creates a rich condition (13.5 AFR) for a few seconds when letting off the throttle as the gas all gets picked up. I can take care of it in software but haven't gotten that crazy with tuning yet.

I had some trouble getting a TPS because I needed it to be counterclockwise to go on the back of the manifold. It mounted very easily, I just filed flats directly onto the carb shafts and the TPS goes right on that. Here's the one I used: http://www.mouser.com/search/ProductDetail.aspx?R=9812R5KL2.0virtualkey68200000

 

Very cool set up.

Its nice to see another FSAE student on the board.

Your 16 AFR seems a bit lean to me. But I not a master calibrator either. Im trying to learn as much as I can about calibration so Im just wondering why you are running at 16. I would think you would want to be around 14 maybe even 13.5 since you are running the blower. Please correct me if Im wrong.

 

Wow... looks great Lapdog, great workmanship. I'm glad to see others doing the fuel injection and other moden improvements to the flathead. I am also building a flathead and will be (trying) to run fuel injection and no distributor. Didn't have the guts to try a blower and not smart enough either. I am making (again trying) to make the injection system look a little like the ford carbs. I will be using the TEC3 system to control the fuel and coils. I like the injectors under the carbs, a nice looking system. Here is a pict of the injection but not 100% complete on the one and a ways to go on the other. I will keep checking on your build to see how it ends up. Thanks for sharing.

 

Zack; I think it's time for YOU to be inducted into the HAMB - "TECH-O-MATIC" society.

So we can keep track; maybe have your OWN HANDLE!!

How about "Flatdog_Zack" ???

Thanks for a great TECH piece from a fellow "Flat - Head" nut!!

 

I call him flatpuppy.

 

Nice work. Definitely one for the archives...

 

As a motorcycle dyno operator I can safely say the most modern motors like the 13.2-13.9 range. 16 is way lean. On race bikes I tend to tune for around 13.9-14.2 especially with oxygenated fuels. I could dig up some runfiles to show you examples of the horsepower differances with what I am talking about if you guys are interested.

I am by no means an expert dyno operator but I have had some great training and quite a few dyno runs under my belt. If anyone is interested in knowing what kind of dyno we use, is a dynojet 250i with load control and a real time air/fuel sniffer, so you can actually simulate real road conditions while tuning in real time. Its a REALLY neat toy .


I was on the fsae team for NJIT when I was in college too, I had TONS of fun.

 

This is really awesome, Zach. I've done PEFI on my autocross car and am now planning a megasquirt install for my hotrod. It's a roadster with a 'Y' block. The plan was to use a late-'80s or early '90s TB from a Ford or Chevy - the kind that has a 4bbl carb base but has two big injectors hidden inside and disquise it as a carb. This will give me a TB that looks like a carb, has injectors hidden inside, and comes complete with a TPS. Hmmm maybe a pair of them on a dual 4bbl manifold...

Your project is awesome. I love new tech hidden in classic looks.
-Ben M.
​

 

Okay,this is Zack, I registered a name for myself. If you see zackbass on the internet chances are that it's me.

Most of the widsom that I've read or heard on the subject has said that I want to cruise lean for fuel efficiency and a nice clean burn. I don't want to make the most power with high vacuum at low to mid RPM, I just want it to to run well while using little fuel. The blower doesn't have any impact on this area at all besides air/fuel mixing, the lower manifold is solidly in vacuum terrirory until about 3500 RPM. I run about 16 in the crusing portion of my map, slightly richer further down to get a nice idle. I decrease my AFR to about 14.5 nearly linearly as I go up in manifold pressure or RPM and then drop it pretty hard to about 13.2 when I start making boost or get above 4500 RPM. The engine makes its maximum boost of about 13psi at 5200 RPM.

 

Did I Read 13 Psi!!!!!!!!!!!!!

 

LOL!!

Flatpuppy (from dad) was funny too.

I agree, 16:1 does seem a little lean. Are you sure your wideband is giving accurate readings? But if it's true and it's not eating plugs or pistons, it is gonna give some pretty phenomenal gas mileage...

 

HAHA, my thoughts exactly. Holy shit, that thing must run..... Any idea of hp and torque numbers?

 

I've heard on this board that Flatdog's car was hauling some serious butt long before the EFI.

I can believe 13psi with a flathead's (relatively) inefficient intake design. Don't shoot me for saying that... Just depends on the supercharger's displacement and drive ratio.

 

I'm pretty sure that's right, the volumetric efficiency of the Flathead is a joke. Having said that though, most people that we have talked to have said that we're supposed to be blowing head gaskets and overheating. After tuning tonight I'll post some datalogs.

 

That's great....I look forward to seeing the track times now.....should be really interesting.

Similarly to others posted before, whilst it would require an entirely new, fabricated intake (below the blower), and I recognise that the huffer would need to sit significantly higher than it currently does, the performance element would be so much better.....

Anyhow, great to see, look forward to seeing more.

Cheers,

Drewfus

 

16:1 is alright for a lean cruise setup. And you are doing good with the 13.2:1 while under boost. I know some more modern engines(LS1, etc.) make peak power around 11.5:1 while under boost. I wonder if the flathead does best with ~13:1

What timing are you running at peak torque and at peak horsepower?

 

Awesome work Zack but Id like to know what kinda timing (both initial and total), ignition curve and static comp you're running too?

Rat

 

Sounds good Zack.

We run our FSAE car with an AFR at around 12.5.
Make sure to keep us updated.

 

Dang,

This has to win for the best ever "What I Did During My Summer Vacation" presentation.

Surely beats: "My first day of summer vacation, I got up. I went downtown to look for a job..."

Mike

 

And...does Megasquirt make a vacuum tube controller for us traditionalists??

 

hey man, when's the next time you guys plan on taking her to a car show or cruise, I'd love to swing by and check it out. I purchased a 49 GMC pickup about 4 months ago that I've been working on getting running again, and am on Rutgers Formula race team (chassic team leader this year), would be great to meet another ME into the whole vintage car thing, HAHA, maybe race our classics out to detroit this year, def drop me a PM

 

Your humour is wasted on the masses....

Danny

 

Rad setup Zack, call me up next time you take it to the drags.

 

Well, I sure laughed about it.....

 

There really were vacuum tube electronic injector systems...briefly. I think 1957...Nash, Chrysler, Pontiac, and Chevy introduced FI at around the same time, with lots of hype. All except Chevy were recalled very soon and exterminated by the factories...
If I remember correctly, the Chrysler and Nash ones--Nash ain't right for this period, I think...were Bendix electronic systems with a primitive electronic brain! These are DIRECTLY ancestral to modern systems; Bendix sold the whole mess to Bosch, and as computers and solid state stuff developed the system became practical and the most generally used type...
Anybody have any documentable detail? This is all from an old and very dimly remembered article.