Next begin searching for desert dry Pinto doors. There have to be a few left. Oh, right, they said that about the passenger pigeon....
Next begin searching for desert dry Pinto doors. There have to be a few left. Oh, right, they said that about the passenger pigeon....
Good idea Turner.
The color match is... well they are both blue:
New door seals installed. While not perfect, this is better than it was before, and should slow the corrosion down a bit.
The fuel fill had to fit into a tight spot on this car to work with the cell. It's always been difficult to fill, requiring a very slow flow rate. Lets see if it can be improved. The cell originally was vented with a long 3/8 hose with a filter on the end. To improve the filling rate the idea was to route the cell vent to the top of the filler neck, then add another fitting from the filler neck to the filter.
First, cut a tube and add some barbs:
Then drill a hole and weld onto the filler neck:
My stainless welding has improved since building this originally.
Then hook it up:
At first, I cut a rubber seal to sit in the neck to try to keep fuel from overflowing . On the first trial, the fuel could flow at full speed! However, the pump didn't shut off when the fuel backed up in the neck leading to spilling. After removing the rubber seal, the pump can run at half speed, and will shut itself off before overflowing. This is a vast improvement!
Sometimes it's the little things that make a big difference! Nicely done
Thanks Racingsnake!
I agree, if there is a bunch of little stuff reminding you the car isn't quite done, it gets hard to ignore. When everything you touch works, its really enjoyable.
To finish up the fuel venting system for now, a quick fuel catch tank/breather that will be routed to the top barb:
Next up on the car, improve the passenger experience. My catch can has been extremely effective, and since adding valve cover baffles, has mostly collected watery/oily scum. The issue, is that the location of the catch can means that the passenger airflow picks up some of the steam coming out of the catch can when the engine bay gets hot. After considering a few options to rework the catch can, I decided to try a traditional pcv system first, to see if the catch can is really necessary.
So, buy a pcv valve and grommet for a 302 powered truck, drill a hole in my valve cover, and add a hose barb to manifold vacuum at the back of the carb.
This experiment seems to be promising. Before passing judgment, I'll need to retune the carb. I'm thinking this may be the final tune for the carb, as I have hardware building up in my garage for the next stage. For now, I have returned the idle feed restrictors to stock size, and returned to the stock secondary spring. The car seems to run well, but its a bit sloppy with a stab of the throttle, and at half throttle acceleration.
While considering new reinforcement of the radiator support link, I removed the link and did a bit of exploring. To my surprise, the passenger side of the radiator support was far less rigid than the drivers side. It turns out, some of the sheet metal that connects the frame rail to the radiator support and the fender well was cracked. This discovery seems to confirm that there has been more vibration on the passenger side than the drivers side. The area that is cracked is tough to access without some proper disassembly. So to test the theory, I whipped up this bracket:
As you can see this area is easy to access, and there is a bolt that goes in the top from the engine bay with another fender washer. Hopefully this will help pinpoint the areas that need reinforcement in the front.
The Bean is still one of my favorite builds on here. i'm always happy to see it on page 1.
I figure anyone knowledgable at least likes Pintos, the haters do not grasp the car's geometery or philosophy.
So, to continue the current effort to make the car solid, reliable, and confidence inspiring, I decided to swap in a rubber transmission mount. When I built the car I used the poly mount that came with the transmission. After chasing vibrations and shakes for the past few years, its finally time to try a rubber mount. Here are the two mounts side by side:
Unfortunately, although the car was originally built to be very serviceable, there have been many additions since then. In order to get an impact on the transmission mount, I needed to drop the cross member. To do that, I needed to drop the y-pipe. Finally, the mount was swapped:
That was pretty easy, but while its out...
Lets swap in those v-bands on the shelf:
Next, we just have to pull the headers to weld... But now that there is a brake booster in the engine bay, the drivers side is trapped.
...
No problem, disconnect the brake pedal, unbolt the booster, pull out of the way... no dice.
Lets pull the spark plugs... still no dice.
It was at this point that I realized I was pretty deep into disassembly for a transmission mount swap...
So in an uncharacteristic move, I pulled back from the scope creep cliff, and reassembled everything as it was... whew!
Hopefully the transmission mount is a positive change. I'll tackle the v-bands later, back on the shelf for now.
Wow...
Very pleased to report that the rubber transmission mount has made a world of difference. So much so, that I might think about replacing the poly engine mounts at some point. For now, I am very pleased.
I've decided to focus on the brake feel again. To give a bit of background, the pedal feel has never been very good since the addition of power brakes. Unfortunately, I changed quite a few things at the same time. Also, I don't have a reference point for what a stock NA/NB miata brake pedal feels like. The pedal has a good amount of effortless travel at the top. This travel does seem to exert some braking force though. While looking over the miata pedal assembly I noticed the miata has a top position pedal stop. This stop is absent on my setup, so lets add a stop and see what its effects are:
The rod from the pedal to the booster has about .25" of free play before the output rod begins to move with the car off. So I set the stop to take up this free play and went for a drive.
After about 6-7 minutes, the brakes started to drag, and quickly started to lock up. After removing the pedal stop, the brakes released and returned to normal operation. I am interested to hear what peoples thoughts are on what might cause this. I have a few theories, but not enough data yet.
In reply to Shavarsh :
You took at least .010" too much free play out. The pushrod must have zero load for the relief valve in the master cylinder to open. As an aside, I have raced in Spec Miata, and raced one long before I drove a few on the street. By my preference, I would disable the booster every time if it was legal to race. The booster masks the feel away at initial bite, and again near threshold. Alas it is not legal to race that way.
In reply to TurnerX19 :
That's valuable feedback Turner. I may just not enjoy the feel of this booster. As a next step I ordered new pads and rotors all the way around. The set currently on the car is from the junked race car that I dissected for parts. At least the rears have visible taper on them, and the fronts seem to be transferring pad material to the rotor. I think starting fresh should cut down on some variability.
Another vote for manual brakes. Better clearance around the motor for sure!
In reply to Shavarsh :
Tapered rotors always cause a long pedal with new pads. Add that to the ugly feel and I know you are unhappy.
Sunday was a great cars and coffee event with the SCCA. Great to chat with some friends and see some other builds, and the car ran great. I've been holding off on the next big project for this car for various vacations and events, but after returning from c&c and realizing I had a full day to play, it has begun...
Starting Point:
Alright, now that we have the pesky carb and distributor out of the way...
Ahhh, I've been waiting awhile to start this project. I have alot of the parts, but not everything yet. I was worried about hood clearance, and worried i wouldn't like the aesthetics of the new manifold. However I am impressed with how the mockup looks, and as you can see there is tons of clearance. More to come.
I'm interested to learn how this stock manifold affects your powerband vs the dual plane/carb. Are you planning on other changes at the same time, or just the fuel injection retrofit on its own?
Gumby,
Good question. Now is as good a time as any to summarize the plan. First an STM Pro ECU:
This is an stm32 based ecu running speeduino firmware. It will allow me to run sequential fuel/spark on 8 cylinders.
So the plan for fuel is:
The plan for spark:
So, as you can see in the above photos, the valve covers are too tall for the intake manifold. Lets fix that:
The welding was fun, but the valve covers are definitely clear anodized, which added difficulty.
Here is a shot with the 3/8" intake spacer:
Here is one with no spacer:
They aren't finished as I need to add a fill tube, and nipple for pcv intake, but they will allow me to keep dust out of the motor for now.
In reply to Shavarsh :
Some nice welds
In reply to Nukem :
Thanks, it's been awhile since I've welded any aluminum. They aren't too pretty up close but should be good enough to hold oil.
The engine has always had a tick since I put it together. I have suspected a collapsing lifter since the beginning, and had an extra trick flow lifter on hand for whenever the intake came off next. Well... 5 years later, the intake is off. So lets try to find that tick.
Passenger side rockers, pushrods, and lifters out (except for the 2 trapped ones on the ends)
Next pull the lifters apart:
As you may be able to see, the wear pattern on the top piece of one of the lifters is a larger diameter than the rest. Turns out the oil regulating washer was upside down. This is likely the lifter I shimmed solid to measure for pushrod length. I must have put it back together incorrectly. This is the prime suspect, although I have my doubts that this would have caused the noise I was hearing. When I tried to push the plunger in on each lifter, they were all pumped up and couldn't be collapsed by hand. The other main suspect is the exhaust lifter on cylinder 7. It was tight in the bore and was difficult to remove by hand. Here are some pictures of suspect sweep patterns and gunk on the intake valves, just for documentation:
Cylinder 6 was a bit darker than the rest. cylinders 5,7,8 look like the above picture.
So, the lifter with the upside down washer was replaced, all lifters were cleaned and reassembled:
I will probably do the drivers side as well while its apart.
After taking all of the drivers side lifters apart, I found 1 that had the oil washer upside down. I know I only took one apart when I put the motor together, so at least one was like that from trick flow. I replaced the lifter with the upside down washer on the passenger side, but on the drivers side, I just reassembled correctly. The exhaust valve on cylinder # 4 has a crumbly spot on the tip, almost like a chip, or material defect:
This is not an issue for today, so it goes back together for now.
Next I focused on getting the lower intake ready to install. Along with the valve covers this will get the engine mostly sealed back up so I can start working on clearing out the old wiring.
First, grind down the chipping surfaces, and clean everything thoroughly. I'll skip the cleaning process for now and revisit it with the upper manifold. My father had the brilliant idea to mask the injector holes with clay. So out came the dollar store playdough:
Meticulously following the instructions:
And finally some post treat with a hair dryer to get a nice even wrinkle:
This is my first attempt at wrinkle paint, and so far I am quite pleased. I hope it holds up well.
Lashing hydraulic lifters is comically easy with the intake removed. I think that is the answer to the hundreds of ticking lifter threads online when confidence in lash settings is in question. A quick visual check after the 1/2-3/4 turn shows approximately the same lash on each lifter.
Next, get the lower manifold on.
After a 1 hr cure @ 200°F:
Even though I know better, once I get a tube of RTV in my hands, there is no stopping me.
Finally torqued down:
Then, a bit of quick and dirty estimation to break the analysis paralysis and get the wire run list finished:
You'll need to log in to post.
