SkinnyG's V8 Pontiac Firefly

Injectors not big enough? 

Couldn't sleep  this evening, so I got up and mucked around with TunerPro software to figure out how to re-map the TBI for the new engine. I have experience with Megasquirt, but not this.

gearhead-efi seems to be a good source for GM bins.

Oh.  My.  Gosh.

21° max at full throttle?  No wonder the 305 TBI is a gutless turd. Peanut cam aside.

Was breaking in the cam in the 350 on the test stand at work, when the upper rad hose blew off (my fault). Engine was totally up to temperature, too.

1st and 2nd degree burns on my arm and abdomen. I hurt. I hurt a lot.

Good times.

In reply to SkinnyG :

dude, that sucks a lot.  i hope you had the GoPro running!

Seriously, though, Glad it wasn't worse. Heal well.

Didn't get me in the face, though, so I'm still devilishly handsome.

Some of the skin is bubbly on my tummy, and my arm skin is pretty wrinkley.

One hour 'till my next Tylenol.

You don't fully own a project until you've bled on it.

I didn't want to pay what they were asking for valve cover bolt spreaders, so I drew these up in Fusion 360 and cut them on the school's Baileigh PT22 plasma table.  My first CNC project:

Also got the engine running on our test stand.  I still have an oil leak up front to fix (Speedi-Sleeve?).

Turns out you can't actually bore a TBI intake out to fit the 2" Big Block unit.  You hit the water jacket.  Good thing I have two more intakes.

Front seal appeared to be leaking like a mofo.

I had a kid rebuild this motor three years ago, and while we put in a new front seal and the harmonic balancer looked ok (it had been Speedi-Sleeved), it leaked like a mother back then.

Taking a good look at the leak from this new front seal (maybe the kid installed the seal wrong?), I wasn't convinced it -was- the seal.

Bolt missing in front of the fuel pump mounting.  I plugged that. No change.

I took it apart and pounded in a new seal, as well as replaced the Speedi-Sleeve with a new one.  No change, but then I saw oil weeping from the driver's side timing cover locating pin through the cover.  So, I pulled the balancer off again, pump, and popped the timing cover off.  Cover was slightly dented around the pin area - I must have missed that.  Hammered them straight again and a nice smear of Permatex Black, and we'll see tomorrow if it still leaks.

Marked out where to clearance the factory TBI intake for the 50mm TBI unit. Knowing how little meat there is in there, I'm pretty gentle on how much to cut.

Then I need to trim the center bolt holes on the intake to fit the 882 heads.

Moates chip burner and chip arrived today, though for a fleeting moment I debating just running a Rochester......

I've been toying with TunerPro for a few days now, and familiarizing myself with GM TBI tuning.

Tonight I burned my first "tune" merely using more traditional SBC spark settings, but I also disabled EGR (there is no VSS in this trans), turned off speed limiter, turned off VSS and EGR trouble-able codes.

Apparently, if I tell it we have a manual trans, I can program a shift light for whatever rpm I want.

I haven't found any sort of rev-limiter in here.....

I soldered the new chip socket into the ECU, and we'll get to tuning once the engine is in.

I'm going to be in the neighbourhood in the next few weeks and would love to check out your projects if possible. Too new a member to PM, hope its ok to leave this here.

I missed the updates about getting burned.  That sounds pretty awful.  I hope you're healing up alright.

Crazy about hitting a water jacket in the intake like that.  Wonder if an aftermarket intake makes sense here.  

There are aftermarket intakes, but I have more TBI intakes.

Today I altered the center holes on a TBI intake to fit the old-school heads.  Also carefully marked the throttle bores to 2" and blended them in about 3/8" in with a carbide cutter.  WD40 makes for a good dipping sauce to keep your carbide from clogging up with aluminum.

Savage, once I'm posting on here that it's back and running again, let's meet at Timmy's.  Double-double and honey crullers, my treat.

I hate those automated "chats" that pop up on various websites. I'm not convinced they are real people.

Oh crap.

Apparently you cannot use the old-school intake gaskets with a TBI intake - you need to have a restrictor in the coolant passage at the rear.  Nuts.

Apparently I'll be picking up proper gaskets tomorrow.

The 350 is sitting on the floor of my shop now.

TBI-specific intake gaskets are on.  Also had to buy a 153-tooth flexplate for the two-piece crankshaft.  I have stacks of flexplates for both one and two-piece cranks, but not one is 153-tooth.

I know I could run the larger flexplate, but I don't have any extra matching starters.

Cheap is fun, but it certainly opens you up to a whole world of new disappointment.

In with the new.

The EGR got a block-off plate, and the intake got opened up to fit the Holley big-bore TBI unit.  I frankensteined a factory GM injector pod onto it.

Notice the size difference between the two.

So far I have the fuel system and sensors all hooked up. Needed to take a break to get refreshed.

Today: Remove collector flanges (not enough clearance, previously), weld collector to header in preparation for band clamps. Install headers. 3hrs.

Still have to install plugs and wires.  That's another 2 hours.

Plugs are mostly in.  One didn't make it (cracked).  The plugs that did now have wires.

To put the plugs in, you need:

* 3/8" ratchet

* 5/8" spark plug socket

* 5/8" wrench

* 5/8" stubby wrench

* 3/4" wrench (to turn the spark plug socket)

*3/4" stubby wrench (also)

* Longer fingers.

Front four go in through the top, back four go in through the bottom.

As an aside, to put the headers in, you need:

* 5/16" long Allen wrench

* Stub of 5/16" Allen wrench, cut to 3/4" length

* 5/16" wrench

* More knuckles and wrists.

OMG the starter was hell to get back in. Kind of like taking an old-fashioned typewriter, and shoving it up your bum.

I cut off the header collectors, and welded them onto the header. I switched to band clamps, since clearance is a premium.

You did a great job making something fit where it didn't want to.  As a result, some things are more difficult to work on than others.  It's the price of awesomeness if you ask me.

SkinnyG said:

Kind of like taking an old-fashioned typewriter, and shoving it up your bum.

It's not as bad as it sounds.

Well, it runs.

Not running super happy yet.  "feels" like too much spark timing, but I haven't put a light on it yet.

Brief datalogging through a home-made WinALDL cable was.... interesting. Still working on it.

I am successful at getting TunerPro to datalog through my home-made WinALDL cable.

Reset the IAC, adjusted the TPS voltage, unplugged the ESC and set base timing.  Yay. Timing was Retarded -  I can still say that, even in 2018.

BUT, I'm getting a pretty significant surging at idle.  It will start and run dandy for maybe half a minute, and then it will start to surge all over the place. BLM pulling fuel everywhere. O2 is seeing rich everywhere.  Could be the O2 is drunk.

I confess I re-used the EGR gasket when I fab'd the block-off plate, so I'll get a new one and see if that is the issue.  I hosed the base of the TBI with WD40 to no avail, but I didn't think to hose down the EGR plate.

Grrr.

You know, the more I think about it, the less I'm sure it's a vacuum leak.

Point being: "It will start and run dandy for maybe half a minute, and then it will start to surge all over the place."

The ECU has a 30 second delay on hot restart before going into closed loop. Watching the datalogs, it runs fine until it goes into closed loop and then all hell breaks loose. The O2 is allegedly reading rich in open loop, but the engine seems happy. As soon as the O2 is active and the ECU starts pulling fuel, it surges all over the place.

At another point, O2 is reading really high, so ECU stops looking at it and goes open loop.  Idle is reasonably stable at that point.  

Might pick up an O2 sensor tomorrow.

Replaced the EGR gasket, there was some oily residue under the gasket, so I suspect that was a leak.

Replaced the TBI gasket with a 454 gasket. This gasket covers much better.  There was two suspicious areas on the smaller TBI gasket that looked like it might be contributing to a leak.

Picked up a new O2 sensor.  Old one looked sooty, but nothing glaring.

I also went back to my first tune, so I'm not chasing my tail.

Fired it up, and got a much better vacuum reading at idle...... until the engine went closed loop, and the O2 started pulling fuel out of everything. The O2 signal looked a lot more sober than the old one, but for some reason it's pulling fuel.

Drove it around the neighbourhood, but the more I drove it, the more it pulled fuel. Definitely way lean, to the point of lean misfire and popping through the intake.

I'm suspecting the culprit might be because the O2 is screwed into exhaust runner #2 since I cannot get to the collectors or merge at all. But, I drove this just fine with the old 305, no issues at all, no trouble codes, nothing.  Why can't it work for me with this engine?

So, I'm going to put a heated O2 somewhere in the pipes under the car. I'm not running a Wideband at the moment, I was intending to get it running first, then deal with WB for WOT later.  Later might be tomorrow.

Unless I give up, and wire in the Megasquirt.....

Quadrajet.

Just sayin.

The only reason to have TBI it to be able to tell someone you have fuel injection. Other than that, it's not worth the hassle.