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Car was originally generator- alternator upgrade complete. Under hood wiring upgraded, all accessories are wired through relays.

Triple gauge is oil press., temp, and volts mounted under dash. A/FR and boost are black w/blue LED mounted on A pillar.

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1960 Seneca 225 turbo soon to be EFI

I bought an advance timing light and am trying to learn what I can about timing. Right now, the car likes 19* initial.

Carb now has #72 jet and #65PV

Knowing that I will be adjusting air bleeds when I install turbo, I bought a Barry Grant Race Demon 500 CFM 2 BBL. replaceable air bleeds, modified choke horn, etc, etc, 319.00

Turbo adapter is in hand. Time to mock-up for brackets and exhaust.

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1960 Seneca 225 turbo soon to be EFI

I bought a Flowmaster 4 piece weld together tailpipe kit at Autozone 88.00

Its listed as a fit for an '85 Ford 350 Diesel/ universal truck.

A little cutting and I was able to run a straight shot in the stock location over the differential and out the rear with a turn down. I stopped under the driver seat because I have to fab a downpipe from the turbo, then thread the needle through the torsion bar/shift linkage area.

This changed the personality of the engine tremendously. Absolutely no lag between accelerator depressed and speedo moving. Very smooth off idle. I used a Thrush welded muffler because its all I could find on short notice in stock. Its a little loud, very deep tone. I think It will quiet down some more once I'm pushing the turbo.

Down pipe is looking ok so far. I'm setting up for an external waste gate to rejoin the down pipe 15-18" downstream.

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1960 Seneca 225 turbo soon to be EFI

Barry Grant Carb came way out of whack for /6 application.

Right now I have a good A/F curve- 12.5 everywhere but low RPM medium load- around 11. I would like to check on an adjustable vacuum pot for this distributor, to see if the low A/FR is due to advance curve.

I have a Holley #76 main jet
.034 idle air bleeds
.045 cruise air bleeds

Timing is 22* initial with 30* total

Idle is smooth and consistent @ 650 RPM

No miss anywhere.

I know nothing about carburetors but what I've learned on this project, I have no experience with anything but Holley style. I do not know if a different carb would be "better" or "worse" "easier" or "harder", but I would recommend this carb (replaceable bleeds, 500CFM, 2 BBL) to anyone for almost any application. My jet and bleed sizes are "in the middle", I'm not struggling to make the carb fit or work, I have no hesitation or "flat spots", the 5.5 PV works as designed, fuel economy is decent considering the cam I have and that I can't keep my foot out of the carb.

Out of the box this carb was nearly unusable. Twenty minutes and a couple of air bleed changes made it a very driveable, though inefficient carb. A good night's sleep and a fresh approach made it a monster. It is extremely tunable.

I removed my distributor and replaced the advance springs with a light and heavy from an old points type I had laying around. World of difference over the extremely heavy pair on the later electronic model.

Engine now pulls past 5000 RPM

After a tankful of test and tune on the hillbilly dyno and countless jet and PV changes I got 12.7 MPG.

This tank should be better, I got 16 with the Holley, a rich A/FR and unruly mechanical advance @ 80MPH for 200 miles.

I have replaceable emulsion jets, but I haven't played with them. This is how things are gonna stay until I'm pressurized.

Saturday is set aside for completion of down pipe, installation of turbo, coolant and oil lines. I think the slick set-up for me will be a bracket welded to the down pipe to bolt to the bell housing bracket beneath starter.

Next week I'll work on wiring in the master boost control and maybe installing a vacuum gauge in the intake manifold so I can see the difference between charge pipe and manifold.

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1960 Seneca 225 turbo soon to be EFI

Although overall I am thrilled with this carb and would buy another one, there are some areas the need to be pointed out.

1) Holley bleeds show much better workmanship, to make them work in a Road Demon carb requires decreasing the diameter of the "head" of the bleed to clear the carb body. No great shakes.

2) Holley accelerator pump actuator is superior in every way- the adjustment bolt is bigger, longer, held securely captive. I swapped the Holley onto the Grant.

3) The accelerator pump arm is grossly inferior to the Holley- again, I swapped it for the Holley.

4) My carb came without a timed vac port in the base- again I swapped for the Holley.

5) The Grant base is Billet and a couple of the outer dimensions are not the same as the Holley- This was only an issue regarding the throttle cable and return spring brackets that I chose. Easy modifications.

6) This is by no means a complaint, just an accurate observation. When using a Holley carb in an "odd" application you need a supply of soft parts such as...

Holley bleed kit 190.00
Contains 4 each of all available bleed sizes.

Holly jet kit 40.00
Contains 2 each jet size from #64-#99

Holley PV assortment 9.00 each
Holley PV guide lines are very good rule of thumb, but it is worth it to try different ones at various stages of carb tuning to see what is happening when.

The Grant website lists all the reasons to use their carb and in my opinion, they are true. I believe this carb is the path of least resistance to a blow through.

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1960 Seneca 225 turbo soon to be EFI

Holley's bleed system is interesting when it is adjustable, maddening when it is not.

Although there are 3 separate circuits in a carb, idle, cruise and transition, they are not completely separate.

It seems to me that when selecting a main jet, we are looking for the right one for our car. Every application will be a little different. If your carb has fixed air bleeds, your jet selection is tethered to the bleed size, not dictated exactly but heavily influenced. The bleed allows a fixed amount of air to draw fuel into the intake. A lot like the idle mixture adjustment screws do for the idle circuit. If you have found the jet that gives the right A/FR at the right time, you have certainly satisfied the air bleed, but you may not have satisfied the engine's demand for fuel.

The idle circuit works exactly the same way, with the added bonus of fine tuning via the mixture screws. The car runs on the idle circuit into the transition squirt until vacuum pulls fuel through the cruise circuit. As main jet size is increased A/FR at idle seems to be enriched. With a fixed idle air bleed, you've just got to live with it.

The procedure I used-

1) Grab a main jet- a BIG one.
2) Idle the engine and check the A/FR
3)Rich at idle, install larger Idle air bleed, lean- install smaller bleed.
4) Monkey with the bleed sizes til you like it.
5) Bump the throttle up off idle and look at A/FR
6) If its anywhere on the rich side- drive it and watch A/FR
7) If it is too rich- install larger cruise air bleeds, too lean -smaller ones
Drive it -if you are in a safe range start watching your vacuum gauge and A/FR to see what the Power Valve is doing to your curve
9) If the power valve circuit is "over enriching" (say you're at 12.5 before PV opens and you find yourself at 10 after it opens) try a bigger main jet.
The PV has nothing to do with volume or flow- only timing. Volume and flow are determined by main jet and emulsion tubes.
10)If you try a bigger jet, you may have to change the cruise air bleeds again
11)Check idle A/FR and adjust idle air bleeds if necessary
12)Reset timing and check everything again -timing advance (or lack of it) shows up in A/FR too.
13)If you're reasonably satisfied, check and adjust accelerator pump actuator.


NOTE: Hold a cup under the lower right float bowl screw when removing it. Remove it first and you won't spill a drop of fuel.
NOTE: Put a rag in the mouth of the carb so you don't drop an air bleed into a bad place.

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1960 Seneca 225 turbo soon to be EFI

So far so good. Manifold to turbo adapter is a perfect fit. Clocked the housings so everything blows and sucks in the right places. Oil in next to fender, oil out toward engine. Coolant lines out the bottom via 1/4" NPT nipples, street 90*s into 1/4" to 1/2" reducers to 1/2" x 5/8" barb fittings.


Spectre air filter where battery used to be.


Bracket to support turbo will most likely be a tab welded to motor mount.

Tomorrow will be spent fabbing down pipe, waste pipe and collectors.

I still have plenty to do before boosting the motor but this is an exciting bit of progress.

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1960 Seneca 225 turbo soon to be EFI

I put collectors on so that I can remove down pipe without disturbing the rest of the exhaust. My plan was to route waste 15" to 18" downstream, I managed 12" due to linkages etc. in the way. A/F probe bung is on the other side, easily accessible at the firewall.

I had some Por 15 manifold paint left over, so I gave the pipe a coat. The surface was very smooth so I doubt adhesion is very good. We'll see.



The bends in this down pipe and the mandrel bend over the differential are the only bends in the 3" exhaust.

Because I opted to mount my turbo right off the end of a stock manifold, it hangs low enough to use the motor mount as a base for a bracket. I welded a piece of medium angle stock to the mount and installed longer turbo to adapter bolts that go through the brace and are nutted on the back. Really solid mount.

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1960 Seneca 225 turbo soon to be EFI

After assembling turbo on the car, I realized that I misremembered that the oil return line must exit from the bottom of the center housing. I had to drill a new hole 2-1/2" lower than the first return bung and weld in a new one.

This makes the coolant lines a little tighter than I had hoped. Still very do able but not with parts on hand.

For now I'm running the turbo without a charge pipe as I check for leaks, noises, etc. and plumb the coolant lines. Oil feed is 3/16" steel tube from sending unit.

Three things are immediately apparent by free wheeling the turbo:

1) The turbo really quieted things down. The muffler is unnecessary, other than to comply with the law.

2) The concept of "spooling up" is crystal clear. Up to 1000 RPM no flow from fresh air discharge, past that it starts coming until full on at around 1800 RPM. (NOTE: "full on" is seat of the pants impression only since I have not installed gauge as yet.)

3) I am a child. Hearing that thing sing at 1800 makes me grin big time.

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1960 Seneca 225 turbo soon to be EFI

Stock waste gate is set at 8#. I have set base timing at 5* BTDC and still ping on hard acceleration. Time to wire in the Master Boost Controller.

It feels like the car lost 1000 lbs!

I can't wait to get the timing dialed in so I can work on carb settings and see what the motor can do.

First impression- worth the money, time and effort. Its really quiet- the turbo whine may be louder than the exhaust. It spools up nice, plenty of room for around town driving beneath boost threshold, but touch the gas pedal just a little and its wound up and going!

Hands down the most fun I've ever had- studying, learning, deciding hunting, buying, modifying, installing, testing and now driving.

Its been a six month build and I still have plenty of tuning time to go.

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1960 Seneca 225 turbo soon to be EFI

Great Ken

I cant wait to see some chassis dyno or dragstrip times.


keep up the good work on this build

Keep us posted and MORE PICTURES



Greg

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http://www.youtube.com/hyperpack

I bought a Vortech Boost timing Master used for a good price. I did not realize that this model will not work with distributors with magnetic pick-ups.

I put an old points type distributor in and wired in the timing master. I am able to stay out of detonation by setting initial timing @5*BTDC and setting master to retard 3* per #of boost.

Now I believe I will have to upgrade fuel delivery as I tried to cheap out on pump and regulator.

The car runs and drives really well even when I am pretty aggressive with it, but WOT for any length of time and the A/FR starts to lean out.

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1960 Seneca 225 turbo soon to be EFI

I spent Saturday plumbing coolant lines, installing PTO cable for overdrive and placing a dimple in the side of the down pipe to allow more clearance for torsion bar. Then I started to try to eliminate the WOT 8# boost detonation. I retarded my base timing to 2*BTDC still pinging.

I tried to enrich the carb to get out of it. Still pinging.

I welded the slots on the mechanical advance and took out 7* then set initial at 5* BTDC-no ping.

Sunday was spent testing and tuning the carb to try to get a decent curve.

Its decent, but rich.

I also piped in the intercooler.

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1960 Seneca 225 turbo soon to be EFI

Love the Updates!




Greg

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http://www.youtube.com/hyperpack

The last settings (carb & timing) did eliminate detonation but the cost was performance. I reinstalled the HEI and reset the carb to original 76 jet .034 idle and .045 cruise air bleeds in order to attack detonation from a different angle.

I tried a .030 cruise air bleed and minimized detonation without using the boost timing master, then I installed NGK ZFR6A11 plugs. Ping gone, Zing back but now I only see 7 lbs boost max. I think the richer top end has lowered my exhaust temperature enough to slow the turbo.

I installed a pyrometer just after the turbo as an aid in tuning. 1000* under load is the highest I've seen with this carb setting. I will reinstall the .045 Bleeds just to check temperature while lean. If the temp is substantially higher, I'll insulate the manifold at the elbow in an attempt to recreate the gas expansion while maintaining lower combustion chamber temps.

I also filled up with premium mostly as a precaution, until I'm safely beneath ping threshold, then experiment with regular again.

Engine easily pulls the car through 5500 RPM.

Observation: Turbos seem to like load. I'm guessing that the increased exhaust temperature is the reason.

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1960 Seneca 225 turbo soon to be EFI