My folly - supercharged megasquirt 2L TC or die trying

[TimpanogosSlim]

As got stated over and over in that other thread, I'm setting out, cautiously, to do something I'm not qualified to do, that doesn't need to be done, that i shouldn't do, which will be hard to do right. If at all.

I intend to keep this thread technical and on topic, and will enlist moderator support to that end if needed.

But i want to make it clear up front that i invite you all to bring any technical disagreement or questioning you may have. Philosophical arguments will be ignored and/or deleted.

I believe that knowledge wants to be shared. In fact i have a burning hatred for trades that are predicated on secret knowledge, so i will share all that i learn in this process.

I have a spare engine. Pulled from a junked 2.0 EFI spider which was titled as a '79. I have the bottom end, head, intake manifold, injectors, fuel rail, and throttle body. I have most of the wire harness and sensors. I don't have and don't intend to use the original AFM and TPS. Mileage unknown. Evidence of a prior rebuild, or at least a prior hone and re-ring. Previous owner struck the oil pan hard and broke the oil pump, but the rotating assembly turns by hand.

This may or may not end up in my '77 124. I may go looking for a spider 2000 body to put it in. That is likely to be at least a year or two out, possibly much more.

Starting objectives are as follows:

Horsepower and torque numbers similar to / slightly in excess of Volumex spider - roughly 140+ horse / 140+ torque

Vastly improved low-end torque and extended top end revs.

Street performance, not track.

Commodity rather than specialty parts where possible. Rare vintage parts are out of the question (no OE Volumex if i can avoid it).

Microsquirt v3 + Ford EDIS, MAF, MAP, knock sensors, wide-band O2, data logging. Compression ratio a bit under 8:1. 7-8 pounds of boost.

No annoying compromises like running stupidly rich. I've gotten nauseous driving behind engines tuned like that, and refuse to be That Guy.

Known challenges at this time:

1: Ignorance & general foolishness

2: May or may not have to go to some lengths wrt. bottom-end bearings & con rods

3: Unsure of cam selection - the descriptions of available cams for these engines all seem to refer to NA applications.

4: Source for turbo pistons, possibly 85mm turbo pistons. I'm given to understand that this shouldn't be a big deal.

5: Fabrication will likely become a bear, wrt the supercharger.

6: Need a TPS that will mate to the throttle body and is compatible with MS.

To get a couple questions out of the way:

Q: Why not a turbo?

A: $400 for a turbo manifold w/o turbo or custom exhaust work vs. $400 for a supercharger that will spool a lot faster. I know i can get more boost with a turbo but maximum boost isn't part of the design goal.

Q: Do you know that you'll ruin the transmission?

A: Yep. Or i might not. Or i might have to source a transmission from a 131/Brava.

Q: Do you even know what you are doing?

A: I think I've made it clear that i don't.

Q: What makes you think that you will succeed?

A: Foolishness and blind ignorance. You're welcome to doubt me somewhere other than within this thread.

Q: Aren't you effectively taking another spider off the road by wasting an engine on a project that will almost certainly fail?

A: I can virtually guarantee you that the salvage yard i bought this engine from would have ended up selling the engine as scrap metal had i not purchased it. Another yard here destroyed a 2.0 EFI block just last year. My '77 will continue to contain it's original 1800 carbureted engine for the time being.

Q: Isn't this going to be a massive waste of time, money, effort, and engine parts?

A: Absolutely!

[TimpanogosSlim]

Looks like i need a TPS that accepts a D shaped shaft, and there are Bosch units that will work just fine. Also possibly Ford units, so I'll poke around the yards at some point, probably when i go hunting for EDIS parts.

Yeah, MS can work with nothing but a MAP sensor. or nothing but an o2 sensor. But that's not how i want to do things.

[SoFlaFiat]

I had to subscribe to this one if for no other reason than to not miss the number of posts you find the need to delete.
There are some brilliant, if not sarcastic, members here who will challenge your challenge just for the sake of it!
Good luck with the build and I do hope that the thread works out exactly as you have so clearly defined it should!
Ok, you can delete my post now...
No, seriously, a challenging project is my favorite way to learn!! Go for it!!

[vandor]

About 10-12 years ago, when programmable FI was not quite as affordable as today, some guy on the East Coast built a Volumex supercharged engine for his Scorpion (Montecarlo) and simply installed a stock FI system from a late 90s Saab turbo. Since it was made for a 2 liter turbo engine, it worked very well.

[FiatMac]

Looks like i need a TPS that accepts a D shaped shaft, and there are Bosch units that will work just fine. Also possibly Ford units, so I'll poke around the yards at some point, probably when i go hunting for EDIS parts.

Yeah, MS can work with nothing but a MAP sensor. or nothing but an o2 sensor. But that's not how i want to do things.

There is a Hyundai TPS which has the proper D shape to fit. That is what I have. I am not at home now but will look it up when I get home and post the part number. You will have to fab an adapter piece to mount it. I made one out of piece 3/8" thick aluminum plate stock.

[ORFORD2004]

My TPS from my running megasquirt setup is from Volvo 850.

[TimpanogosSlim]

My TPS from my running megasquirt setup is from Volvo 850.

Aye, it appears that the part to find is Bosch 0-280-122-001 - as found on 88-01 volvos and saab 900/9000 of similar era.

per this thread:

http://www.turbo124.com/forum/viewtopic ... 65&start=0

[ORFORD2004]

And I use the stock piston with Total Seal ring and forged connecting rod from GM 350.

[burgandy81]

Love it!

My plans are similar although I yet to start on the supercharger mounting. My "designs" have bounced around several different mounting options with the two favorite designs being a "Hot-Side Mount" with the blower over the exhaust manifold and a cold side mount with the blower in the place of the alternator on later cars. Miata kits exist for a hot side set up that seem to work well and the Volumex was located roughly where the alternator is.

Miata example: http://www.fastforwardsuperchargers.com/

I used a Lancia intake manifold with lancia TB that came with TPS. Should be able to source on on eBay Germany. (Still have an extra Lancia intake if you are interested).

With your low power ambitions I think stock US spec pistons would be fine.

Some resources for you.

Blower crank pulley source: http://www.millersmule.com/MillersMuleS ... ulley.html

Best MS forum I have found (you probably have found this) http://www.msextra.com/forums/

Some musings on a FIAT supercharger set up. http://www.turbo124.com/forum/viewtopic ... &view=next

An older thread on my MS tuning efforts. http://www.fiatspider.com/f08/viewtopic ... 17&t=19304

Generally I think this is a brilliant idea and Spiders are an ideal platform to hot-rod. This is not the most popular perspective on this forum as you may have noticed.

Best of luck and keep us posted.

Cheers,

Jordan

[TimpanogosSlim]

Thanks for the links! I'm gonna try and keep the original intake manifold and tb if i can.

I'd considered hot side high where the smog pump would have been on some years, and hot side low where the smog pump was on other years. But I'm seriously unsure of room with the low mount.

I was kinda thinking about a Toyota SC12, as found in 94-97 Previa minivans, and some MR2, and other things.

[131]

I started down this path nearly 10 years ago, using my car as my daily driver has been my biggest drawback. I've got everything required to finish it off, manufacturing blower mounts is the current holdup. Everything is available to do this, and mine would be done if I hadn't procrastinated for so long. I've bought and sold bits as plans have changed, I've done a lot of homework and learnt a lot, and a lot of what not to do. I'll be using a Fiat Tempra manifold, throttlebody and tps, bolt on parts from the Fiat parts bin. I started off with an Eaton M90 from a Ford supercoupe, but after exchanging a few emails with this bloke: http://www.hiperformancestore.com/super ... ercharging book, I sold the M90 and bought an M45. A small roots blower is more efficient turning fast than a larger roots turned slowly. I've modified a Fiat crank pulley and mounted a serpentine pulley from a Saab on to it, I can't remember the drive ratio, but I'm looking at around 8 psi. I've sourced a set of 0.6mm oversized Fiat Croma turbo pistons, CR should be around 8:1, but won't be confirmed until I make measurements. A Fiat Regata 100s head has been overhauled then a mild port and polish done, cams will be stock, or I may source a warm inlet cam. I've decided to fit MS, EDIS and injection to my current motor, get it running and sort out the tuning, before fitment of the low compression motor and blower. Hopefully your journey will have faster progress than mine, I find the speed and skills of this bloke inspirational: http://www.turbo124.com/forum/viewtopic ... 11&t=13032

[v6spider]

Dude, do it! It can be done anything can be done with the right amount of research and development. Over 14 years ago I became a member of this forum and with the sole purpose of putting a 300hp+ vortec v6 in a spider. In the beginning that was sort of an unheard of thing and did not receive favorable support here. After I finished the first version I started to get taken seriously.. Now that the second one is running. And there have been some others that have built other spiders retrofitted with other power plants there has been more acceptance.. Don't give up.. You will succeed!

Cheers!
Rob

[TimpanogosSlim]

Huh, Coil-on-plug EDIS is possible, as is dual EDIS for no wasted spark / better recovery time. And these have been used before, though on a 1.8 corolla. And yes, by some crazy ozzie.

The argument i saw was that at higher RPMs a wasted spark system can kinda run out of breath. I am glossing this over hard-core since i don't seem to have that page open anymore. I'm sure an EET would lecture me at length about how i got it wrong.

As long as I'm spending the year scavenging parts from the yards - which fwiw i find therapeutic after a week at the widget factory - why the heck not?

It looks like I need some toyota/lexus coil packs from an early 90's v6 that didn't have a wasted spark configuration. And I'll want to fabricate a hold-down bracket for the coil packs. But i won't be forging new territory here.

Yeah I'll make sure i get an edis4 coil pack so i can start with or fall back on the regular edis4 configuration.

In other news, i didn't bring home the air intake tube or the idle air plumbing from the junked spider 2k. Starting to think this may have been a mistake, particularly if the tube is flat in the middle for clearance reasons. Yeah i have a big bump hood - i even have a 97% intact hood blanket for it.

I can probably fab something out of plastic DWV pipe if it needs to be flat.

It's still possible that a lancia manifold would be easier but like I said I'm gonna try to use the OE manifold. I can use a starion / conquest intercooler or similar to get both ports on one side of the engine bay. Yeah, more length, but time needed to compress the charged air system is probably less of a concern with a supercharger.

[timinator]

Just a couple of thoughts about where you are going with your build. Wasted spark is not rpm limited. If you put 1&4 on one amplifier and 2&3 on another heat build up is nothing. Then use a coil pack or COP. Both use the same ECU drivers.

Intake tract length with boosted systems is not the problem you would think. Cars are running rear mounted turbos or water cooled inter-coolers with very long runs between turbo and intake valve.

No need to impose limitations on your build before you find out what parts are available.

[TimpanogosSlim]

intake tract volume is sort of an issue. You'll notice that STS tries to keep the charge piping diameter small on their rear-mount turbo kits. I have a friend who used to work there.

I recently broke a big hole in the side of the original intercooler on my 07 vw gti, so i replaced it with an aftermarket all-aluminum intercooler that is roughly 2x the volume, and it's been interesting watching the ECU gradually adapt to the larger volume of air it has to compress - but in this case, the original ecu program has the blow off valve partially open when tooling around at low RPMs, so it's gradually, ah, not doing that so much.

But that car has no boost to speak of below about 1800rpm, which won't be as much of an issue on a supercharged system, which will also have a mechanical BOV triggered by intake vacuum.

Just a couple of thoughts about where you are going with your build. Wasted spark is not rpm limited. If you put 1&4 on one amplifier and 2&3 on another heat build up is nothing. Then use a coil pack or COP. Both use the same ECU drivers.

I'll do some more reading on the rationale behind dual edis4 configurations