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Better with Boost: My Turbo Spider Journey

45K views 267 replies 30 participants last post by  nealric 
#1 · (Edited)
EDIT: Working on fixing broken photobucket links.

I've been asked about a build thread for my spider a few times, and realized that the original was languishing in obscurity in the engine conversion thread, as it was originally an ITB build. As explained on the thread, the initial turbo build was fantastic engineering beyond my personal capabilities.

Where the build left off under the hood:



http://www.alfabb.com/bb/forums/engine-conversions/165308-itbs-megasquirt.html

Since I am continuing the project, it's time to post a new thread. As it sits, it's running 5psi of boost (will likely bump to 7-8 sooner rather than later) and probably around 140-50whp (hope to get it on a dyno soon!). I've run it in a few autocrosses and found to be a total blast with the upgraded suspension and brakes. Unfortunately, it would take a pretty wild build to make it competitive in autocross (SSM would be its class with the turbo).

I expect this to be an ongoing project over many years, but my ultimate vision is a spider with around 250whp, T5 transmssion (or if I hit the lottery, the Alfaholics sequential transmission), watts linkage in the rear, upgraded diff, a new paint job with a color change, and perhaps some fender flares for bigger rubber.

But, before any of that, I wanted to get this thing driveable a real track so it's capabilities can be properly exploited. I'm planning on having a roll bar similar to msiert's fabricated in January, and just installed a pair of race seats to get the roll bar fitment squared away. Next will come 6 point harnesses and probably a new steering wheel (the old one hit my legs even with the stock seats).

 

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#2 ·
will be interested to read more. how does your head go with the roof up? I tried some classic style bucket seats in mine but had to send them back as on installation they sat up a bit higher and my head hit the roof.... I see yours are side mount though. is that the trick? or did you change the whole floor as per Alfaholics?
 
#5 ·
very interested in your turbo spider project. my dd is a highly modified 2014 Fiat Abarth. I know first hand, how much you can get out of a small displacement turbo engine. Mine is only 1.4 Liter to begin with. Started out with 160 HP stock, it's estimated to be in the 220-240 HP range currently, but at 20 on the boost side, sometimes as high as 24.

I will be following your build closely. What turbo are you using in this car? One off of a Saab turbo perhaps, they seem to be a popular one with conversions.
 
#6 ·
Heck, there are 4cyl turbos with well over 1,000 hp (not very streetable though). The new Golf R makes 300 stock out of a 2l turbo.

I'm using a Garett t3/t4 .48 housing. Not a take off from any car, but very common turbo.
 
#7 ·
You are quite right, the Garett's are a popular choice in turbo's. There are some in the Abarth community currently working on much larger than stock Garett's, hoping to get to the 300 HP mark. Lots of other issues - special mounts, larger injectors, coil packs, etc.

Me, pretty well finished with mine, and I am sticking to stock turbo that came with the car. Still needs to be a reliable DD for me. 200 plus HP in a 2,350 lb. car is still a decent weight to HP ratio to me, at least.

Good luck with yours, most interesting. Gets me thinking on my own Spider.
 
#9 · (Edited)
Took it out to a track day at Harris Hill Raceway over the weekend. The car performed great- not the slightest hiccup in five 1/2 hour lapping sessions and 6 hours of driving to and from the track.





This was my first time really using a 6-point harness. Really made quite the difference in being able to stay focused on the line rather than staying planted in the seat!
 
#10 · (Edited)
One more track photo came in:



(it only looks like I'm missing the Apex here :p )

Mechanical updates:

Temps were getting a bit up there on the track and summer is fast approaching, so I thought it was finally time to make use of the integrated oil cooler on the radiator my friend installed. Mmmmm anodized fittings...



It was also time to ditch the hot air intake...



Fitment is a bit tight, but it gets the filter into the fender well. The car now makes a distinct sucking noise from the driver's side fender well :laugh:

Next up, I got this from an alfabb forum member:



The brakes were always a bit squishy no matter how well they were bled. Time to go boosterless. Will be adding a remote bias adjuster so I can spin into the wall on command. Because racecar!
 

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#11 · (Edited)
Time for an update. Car was off the road for the last 6 months- did its first drive on Sunday. Turns out having a newborn makes it hard to get work done on cars. Who would have thought?

In June, I had a great time running it in the Alfa national convention at the Corvette museum track in Kentucky.



Lap times were a bit of a disappointment, but I think my driving ability was probably the biggest impediment.

Got the megasquirt wired up to program a boost control solenoid prior to the convention, so I can now blow my motor at the click of a mouse :D Boost is now at 7psi, which is pretty safe, but a nice little kick over 5. This thing will be a beast with a built motor.

In August, I decided to finally get the fancy Tilton boosterless setup in. I thought it might be done in a weekend or two. HA!

After taking apart the dash for the pedal box, the first order was to install the nice Sparco steering wheel I had ready to install. My legs finally fit properly!



Removal of the old system was pretty straightforward. The old brake booster probably weighed 20+ lbs! Then the hard part. Spruell Motorsport developed a conversion plate advertised as working on all 105/115 series Alfas for the Tilton setup they I purchased from an Alfabb member. However, I soon found out the conversion plate was the least of my worries. I would like to thank Paul for answering my fitment questions- he was very friendly and prompt. It turns out that you have to remove a "pocket" in the firewall in order to make clearance for the pedals. Wouldn't be so bad, except the main wiring harness sits right behind it. To avoid cutting the harness, I spent hours and hours slowly and laboriously cutting it out with dremel cutoff wheels.



On top of it, the steering column bracket on later cars such as mine interfered with the pedal travel, so I spent hours more grinding it down to make room.

And then, the pedal box didn't fit.



Turns out, later cars have an indentation to the right of the booster that earlier cars (presumably the cars this setup were designed with) don't have. So that took some quality time with the BFH to hammer out the indentation. After endless tweaks and test fits, I got everything to fit! Since getting the pedal box in involved removing the HVAC blower and heater core, I decided to go full racecar and delete the whole system along with the radio.



The plate at the bottom that retains the lines will eventually be used to attach a heat shield. I've also made a rubber grommet to keep the lines from rubbing. Not shown, the redo of all the brake lines. This was my first time running and flaring brake lines. A bit of a learning curve, but no leaks :D I also had to delete the stock brake proportioning valve that ran under the car, as it would override the bias adjuster.

The cherry on top was a nice powdercoated valve cover!



Initial driving impressions: Man, you have to brake like you mean it with a boosterless setup! But I can see how it will help a lot with modulation. I may end up swapping master cylinder sizes if I decide I'm tired of being he-man. There's still a big to-do list before it's ready to go back out on the track.

1) Clean up the wiring. As you can see, it's still a mess! That old pocket and the HVAC stystem were part of the wire retention system, so a new one will need to be devised. I'm in the process of replacing the wideband AFR guage after my old one conked out on me (that's the coil in the corner).

2) Rebleed the system with proper high-temp fluid. I used the cheap stuff while getting the system sorted.

3) Put the interior back together. The bias adjuster is where the a/c knob used to be :p

4) Start playing with the bias adjuster to get it where I want it.

5) Install new guibo and shield that I also bought from Spruell

6) Fix the fuel gauge that decided to crap out on me.

.... And those are just the needs. The wants will keep me busy for years. I've dropped the transmission swap idea for now. The stock Alfa box gives it character, and I think a lighter clutch/flywheel combo will improve shift speed quite a bit.
 

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#17 · (Edited)
Alfaparticle, I'm installing Paul's "ultimate flex disk kit". I found your thread, and your setup doesn't seem to have the cages.



Or did you end up trying the other sort?

In unrelated news, I decided to make myself a new throttle pedal out of some aluminum angle over the weekend. This gives me adjustable angle. Stock pedal was too horizontal and too high for heel-toe.



Coated with plastidip rubberized coating for grip and installed:



Wiring is still a work in progress, but I did manage to get rid of the old aftermarket radio harness from two owners ago.Lots of questionable connectors lurking in there!
 

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#19 · (Edited)
A few small updates. Had time to get the driveshaft out over the weekend, but I got a bit stuck with the driveshaft cage installation due to being a bit befuddled with the instructions. I have a note in to Spruell asking for clarification.



(the garage floor of beffudlement)

In other news, I decided that I wasn't fully happy with the current brake setup. Even with 3 bleed attempts, pedal travel was too long, and modulation wasn't great. Besides, my rear calipers were probably in need of a rebuild. So, I contacted Alfaholics in search of glorious (wretched?) excess. These came yesterday:





(not pictured, rear Alfaholics calipers too). Are six piston calipers remotely necessary on a 2300 lb car? Absolutely not. But they do look lovely. While I'm at it, I plan on installing longer plungers on the brake master cylinders in order to fix my pedal positioning (which is too far towards the bottom of the arc on the pedal).
 

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#20 · (Edited)
It's been a while since last update. Having a baby boy around certainly doesn't speed up the build process, nor does a hurricane dumping 50 inches of rain, but it progresses slowly but surely.

After futzing with it the entire summer, I finally got the Alfaholics/Tilton brake setup fully installed and (mostly) tuned to my liking. Bleeding turned out to be quite the ordeal- the pressure bleeder just wasn't getting the air out and buddy bleeding properly requires 3 people working in concert on a dual master cylinder setup. After all that, I'm still toying with the idea of going up one more M/C size. The modulation and stopping power are great, but pedal travel is a bit too long for heel-toe rev matching under hard braking.



The bias remote knob is now installed where the HVAC blower was supposed to go. After doing that, I've decided I need to make a new faceplate for the center console, that will also have a mounting location for a remote cutoff switch.



New Alfa logo centercaps help round out the look. Next up, I have purchased a new motor and rear end to start tearing into :grin2:




Plans for the rear end:

1) Clean and make pretty.
2) Replace bearings, diff gaskets, and refresh e-brake
3) New differential: Alfaholics or OS Gikken from Spruell?
4) Alfaholics halfshafts? Worth the coin?
5) If I can find the holy grail, a 3:73 ring and pinion

Plans for motor:
1) Forged pistons/rods. Either 8:1 or 8.5:1 CR
2) Ductile liners? O-ringed/piano wired. Epoxied?
3) Headwork? Probably nothing too fancy.
4) 20psi of boost
5) Silly amounts of power
 

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#24 ·
Well, it looks like the next-level for the build will happen a bit sooner than I had originally anticipated. Last month, I took the Spider autocrossing. It was running great, but I had zero traction in the cold weather and on summer tires with way too many heat cycles. On the way home, the car started sputtering and my wideband 02 gauge started showing way lean. Ended up having it towed home.

My first inclination was fuel pump, and it was due for an upgrade anyways and I had no idea when the filters were last changed. After replacement, the car seemed to be running ok, but I kept having odd misfires (and of course, the wideband shows full lean when the engine is misfiring). This last weekend, the problem presented itself more directly:



Yep, that's coolant coming out of the head gasket. Time for a built motor. Was hoping to push the stock motor for another few trackdays, but I have to admit it took some pretty hard abuse before giving up the ghost.

Took the opportunity to start disassembly of the motor I bought a few months ago. It turned over freely, but it was a little gross inside. I think it should be Ok as a core.



Plans for the new motor:
Mild headwork- at least a valve job and port and polish. Not sure if it's worth messing too much with cams on a turbo setup.
Forged pistons/rods. Current thought is 8.5:1 compression. A touch lower than stock, but hope is the head work will keep off-boost response similar to where it is now.
Additional oil passages for #2 and #4 pistons
Ductile iron liners- o-ringed and piano wired to hopefully prevent future head gasket failures

Last, but not least: 15-20psi of boost. Target will be 300whp, though the beauty of the boosted setup is I can run less boost for a tamer car (and drivetrain preservation) most of the time.
 

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#25 · (Edited)
It's been a while since my last update... but I have some stuff worth showing. More to come tomorrow as I get around to taking photos of what I've been up to.

I spent more hours than made any rational sense getting the old block cleaned up. The steam cleaner helped a bit, but man it was hot work. The old engine looked pretty clean from the outside and turned over nicely, but it must have had just water in the coolant system for some time. It was corroded badly. Fortunately, it was the liners that took the brunt of it.

Old motor is out as well. First time in this car went surprisingly smoothly. Without the clutter of the stock engine bay, everything went pretty smooth. Took around 5-6 hours of work to get it ready to pull. The pulling itself went down in under 10 minutes. With the motor out, I've started stripping the engine bay. This baby is getting painted!
 

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#26 · (Edited)
As for the build itself, key items have arrived! (more photos to come):

Rear end:

OS Gikken LSD
Hydraulic handbrake conversion from Alfaholics
Alfaholics Watts Link Kit


Head:
"Stage 3" Head From Steve Hannaford at Progressive Automotive

Bottom End:
8.5:1 Pistons from JE
Darton Sleves
Carrillo H Beam Rods
Windage Tray From Spruell
King Race Bearings
Spruell "Race" Timing Chains
Surpell "Race" Motor Mounts & Transmission Mount

Oil Control:
Oil Pump by Gordon Raymond
2L Accusump

Clutch: Alfaholics "Fast road/rally" Clutch with 10.5lb Aluminum Flywheel

I have to say the oil pump rebuild by Gordon was worth almost for the write-up and service alone! He turned my pump around in under a week with 20+ photos and a very detailed description of the rebuild.
 

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#27 ·
Pictures as promised! I went at it with the teardown today. The question was: will this thing have carpet when I am done? I'm tired of taking things apart, but I decided I've gone to far and I need embrace the racecar. With the seats and carpet out, I was met with some incredibly nasty insulation. I then commenced to 3 hours of chipping away at the coating over the floor pan. I think I have at least another 3 ahead of me before it's ready to prep for paint.
 

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#28 ·
Engine bay is almost fully stripped. Can't figure out what to do about the steering box. It will be hard to push the car around once it is out, so I'm reluctant to pull it now. Wonder if my painter will let me do it at the shop? Also, mock up of where the Accusump will go. It's going to be a tight fit with the turbo, but it should just squeeze in there. Lots of cleaning left to do for the engine bay. It was filthy!

https://www.alfabb.com/bb/forums/attachment.php?attachmentid=1518180
 

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#30 ·
Final post showing the goodies.

Carillo rods came out to +- gram as expected. Sleeves are interesting. Instead of having flat sides like the stock sleeves, they are round. Despite having less material, this should be a much stronger design. Note also the groove for the "o-ring" of piano wire that will bite into the head gasket. I still debate whether 8:5:1 was the right call with the pistons. I suppose proof will be in the pudding. Alfaholics flywheel nice and shiny.

Finally, dropped the block and crank off at the machine shop today. It's getting drilled for additional oil passages. The crank will be polished and the oil pickups chamfered. Machine shop is not an Alfa place, but they specialize in race motors and were intrigued by an Alfa project!
 

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#36 ·
No dyno yet. I had plans to do some dyno tuning before the head gasket blew. It was good enough to chirp third gear at 7psi on older 200 treadwear tires. Plan is for ~300hp from the built motor in high-boost mode although I will likely run a low-boost tune for safety.

Unfortunately, the manifold is a one-off but a basic log manifold is not terribly difficult to have fabricated. You can even buy kits for fabricating tubular manifolds, but that’s a more difficult proposition. There are also turbo manifolds floating around from the old Jafco kits but you’d probably want a new flange welded on to run a modern turbo.
 
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