another weber install (3A-KT)

General discussion about our beloved Tercel 4WD cars
Kumppari
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My tercel:: 84 4wd
Location: Finland

another weber install (3A-KT)

Post by Kumppari »

Hello all!

Yes, i also swapped my stock carb to weber. The difference to most other installs I have seen on this site is that my weber is DAT32. Those of you that know your webers, have probably allready guessed what kind of mod this truly is. For the rest of you who have never heard of this carb before (like me) here is a hint:

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Yup, its desinged to work under pressure :wink:

The whole project started as a stupid/crasy idea. I needed something to pull my jetski out of water, and generally tow it around in trailel during summer, and commuter for going to work during winter. So I bought a tercel (paid 550€ for it). It soon became apparent that 1.5 liters is a bit too little for dragging 500kg trailer. I had the turbo and carb lying around from a nother project that my friend and I started, but never finished. So I tought, why not :D . I started by removing the head and changing the head gaskets and valve stem seals. Intake valves were good, exhaust valves were little burned, but nothing too bad. Also, a pleasant suprise was that on top of the pistons was number 0,50 witch explans why the engine doesent consume any oil. Othetr than that, no big proplems with the head or manifolds, and only two broken bolts. No pictures, sorry (forgot to take any :oops: )

The real work started after I got the head back on. First thing was to get the turbo in place, so I started workin with the exhaust pipe and manifold:

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Being lazy :roll: I decided to go the easy way and used the original manifold. I chopped the flange off from my original exhaust pipe and attached two 90 degree bends in it, and on top of those, the turbo flange.

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Exhaust side and downpipe is in place, witch is made from all sorts of junk pieces I had lying around. it connects to the original pipe just before the first silencer. Also in the lower picture you can see where I made the oil retun. I was going to do it properly in to the oil pan, but it seems to be pretty nasty job of removing it while the engine is in place. So I just drilled a big hole in the block (yikes) put some theads in it and attached a suitable fitting. It doesent even leak, yay! The important thing is to drain the olipan AFTER you have made the hole so that the shavings come out with the OLD oil. Ask me how I know this...

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Rest oft the turbo is in place, onwards tho the carb. It didnt fit straight, so I had to make an adapter plate.

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Front side with cable operated choke and pressure lines going to the fuel pressure regulator and waste gate actuator. Also visilbe at the bottom of the picture is oil pressure line, which comes from the oil pressure warning light.

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Throttle linkage is taken from the original carb.

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All done! Notice the fancy color of the fuel lines :mrgreen: goes well with the car colour. Fuel pump is located in the firewall in front of driver, and is making a hell of a noise. Have to do some sound insulaiting bracket for that. And no itercooler, yet. Wont bee needing one sice winter is coming, but I will install one next spring. Also my boost pressure meter is currently danglin from its hose, spinning in the passenger side floor :)

So after I got it all together enough to get it started, me an my friend (holding the boost meter for me :lol: ) went for a spin. And no boost :cry: We stopped, and after awhile found out that the waste gate actuator linkage was not connected :P This fixed we try again, and WOW what a difference compared to stock! With only 0,2bar the engine pulls easily in the top rev range as high as 7500rpm, and propably more, while still making plenty of power. boost starts to rise very early too, around 1700rpm there is already 0.1bar, so low down torgue has improved also. Ofcourse we had to start raising the pressure, and around 0,4bar the clutch started to show sings of slipping :? we also quickly discoverered that my driver side front brake is in need of some R&R. And since I dont have intercooler yet, we backed up the boost a bit an announsed it succsesful test drive, went back to home and cheked for leaks. None, only bit too much coolant in the bottle. so all in all I am happy, and waiting for the first snow to fall so I can start to drive with 4wd on! :D

Thats it! Feel free to ask, and try to ignore any spelling errors, as Iam not native English speaker.
Last edited by Kumppari on Mon Sep 29, 2008 4:00 am, edited 2 times in total.
My other toyota is a toyota (mr2 to be precise)
Teddy
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Location: Seattle

Re: another weber install

Post by Teddy »

Kumppari,

That is some sweet hotrodding, dude. You have built yourself a 3A-KT (Toyota 3A-Kumppari Turbo).

What Maserati, Fiat, Abarth, Lancia or Alfa Romeo are those blower parts from?

I suspect as long as you keep retarding your timing and running rich, you should be able to keep dialing in boost.

Bravo!
Kumppari
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My tercel:: 84 4wd
Location: Finland

Re: another weber install

Post by Kumppari »

Teddy,

Turbo is garrett t25, most likely from nissan bluebird (dont know what its called elsewhere) but it is used in other cars also. Carb, I have no idea if its used in some cars from factory or is it aftermarket item only. Only thing I know of mine is that it was attaced to ford ohc intake manifold when I got it. funny thing was that when I drove whitout pressure it run horrilbly rich, but as soon as I got my waste gate working, the carb started working too. Seems that it has been in roughly the same size engine before, as I havent touced it at all. Lucky?

3A is very strong engine, and I have no doubt in my mind that it would not handle more pressure, with intercooler and a proper exhaust pipe (the stock is VERY restrictive). But then it would most likely destroy clutch, transmission, and rest of the drivetrain. so I am going to leave as it is, and try to shift gently :wink:
My other toyota is a toyota (mr2 to be precise)
takza
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Re: another weber install

Post by takza »

Kumppari wrote:Teddy,

Turbo is garrett t25, most likely from nissan bluebird (dont know what its called elsewhere) but it is used in other cars also.
If I remember right this is the turbo used on the 280ZX and early 300zxs...a 3L engine. Don't turn the boost up? :mrgreen:
Give a boy a gun-give a biatch a cell phone-and pretty soon you almost got yourself a police state.

Orwell said: War is peace! Freedom is slavery. Ignorance is strength...

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GTSSportCoupe
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Re: another weber install (3A-KT)

Post by GTSSportCoupe »

Very nice work! Thanks a lot for sharing this! I've often thought of doing this, but would need to find a nicer tercel 4wd than mine to justify it. Where did you get the fuel pressure regulator? I guess it is a special rising rate regulator? It must always maintain 3psi above your boost pressure or so?
Current:
91 LJ78 Landcruiser EX5
95 A32 Maxima SE
Former:
87 AW11 MR2 Smallport 4AGZE
93 Taurus SHO ATX
86 AL25 SR5 6spd 4wd
90 AE92 GTS
82 KP61 SR5
85 MX73
87 AE86 GTS 4AGZE
85 AE86 GTS
83 AL21
Kumppari
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My tercel:: 84 4wd
Location: Finland

Re: another weber install (3A-KT)

Post by Kumppari »

Takaza,

Im not sure about 280zx, but 300zx was V6, right? That would mean two turbos, 1,5 liters for each. And I have purposefully left that small but very dangerous screw under the hood, out of reach from drivers seat :wink:

GTSSportCoupe,

Yes it is, made by Malpassi in Italy. Rising rate fuel pressure regulator, hence the pressure line going into it. There is also nifty little screw on top of it that you can use to adjut the pressure. Weber recommends 2psi in this carb, and almost every other carb for that matter. I adjusted mine to 1,5psi since the important thing is not so much pressure, but good flow to keep the bowl full.
My other toyota is a toyota (mr2 to be precise)
takza
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Re: another weber install (3A-KT)

Post by takza »

Kumppari wrote:Takaza,

Im not sure about 280zx, but 300zx was V6, right? That would mean two turbos, 1,5 liters for each. And I have purposefully left that small but very dangerous screw under the hood, out of reach from drivers seat :wink:
http://en.wikipedia.org/wiki/Z-car

Talking about the 300ZX Turbo 3.0 L V6....

"For the 1988 models, there were again a few small changes. The turbocharger was switched from the Garrett T3 turbo to a lower-inertia T25 turbo, and the engine from 7.8:1 to an 8.3:1 compression ratio in order to reduce turbocharger spool time and provide instant boost at any usable RPM."

I drove a non-turbo...and everyone with the turbo or converting an na wanted the T25. They got some serious HP out of these cars...some around 350-400 RWHP with intakes...intercoolers...exhaust...high boost.

After '89...they made a twin turbo.

So you've got all the boost you're going to need? :shock:
Give a boy a gun-give a biatch a cell phone-and pretty soon you almost got yourself a police state.

Orwell said: War is peace! Freedom is slavery. Ignorance is strength...

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Kumppari
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My tercel:: 84 4wd
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Re: another weber install (3A-KT)

Post by Kumppari »

A V-6 with single turbo? I always tought it only logical that with any turbocharged V-engine there would be two turbos... I would love to see the exhaust manifolds and pipes in one of those things :) Great looking cars by the way, ecpesially the older ones. And the skylines from that era too.

Ive been doing a bit more driving, and found out that heat soak is a bit of a proplem. The turbo is fairly close to the carb, and also the adapter plate that is in place of the bakeltie spacer, is made of aluminum. This is most only noticeable after any amount of slow driving (off roading). Propably wont be a problem during winter, but it seems that I have to do some refining to the setup at next spring.
My other toyota is a toyota (mr2 to be precise)
GTSSportCoupe
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Re: another weber install (3A-KT)

Post by GTSSportCoupe »

Kumppari wrote: Ive been doing a bit more driving, and found out that heat soak is a bit of a proplem. The turbo is fairly close to the carb, and also the adapter plate that is in place of the bakeltie spacer, is made of aluminum. This is most only noticeable after any amount of slow driving (off roading). Propably wont be a problem during winter, but it seems that I have to do some refining to the setup at next spring.
Maybe you could have the exhaust manifold and hot side of the turbo ceramic coated? And add a small intercooler before the carb?
Current:
91 LJ78 Landcruiser EX5
95 A32 Maxima SE
Former:
87 AW11 MR2 Smallport 4AGZE
93 Taurus SHO ATX
86 AL25 SR5 6spd 4wd
90 AE92 GTS
82 KP61 SR5
85 MX73
87 AE86 GTS 4AGZE
85 AE86 GTS
83 AL21
Typrus
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Re: another weber install (3A-KT)

Post by Typrus »

Go take a gander at a 7.3L Powerstroke. Garret GT-45 if I remember right, sitting up in the valley. Uptubes to the turbo from either side.

Pretty common to single-turbo vees....

Sweet write-up! Albeit makeshift, still awesome!
They make up to Stage 2 clutches last I checked? Should hold your power. However, clutch burn or tranny blow? You decide.... lol.

I want to cryo-dip a fresh Z52F/Z54F... See how much more oooomph it'd take....

Could nab a Garret GT-15 off of an early TDI perhaps. Up to 12PSI boost on a 1.9L diesel that revved to 4600RPM. So It'd feed a Paradise Racing's double-valve spring equipped 8000RPM 3AC to 6PSI any day. Maybe get a little strained higher up, but really revving past 7000RPM regularly probably isn't the best bet on a non-balanced set of internals... We've seen up to, what? 50 grams off balance on the piston-rod assemblies? However we share the same part number oil pump as a 4AGE so oil supply is very unlikely to be an issue, unless internal block flow is constrictive or filter media is too constrictive.


May I suggest idling your engine for 60 seconds before shutdown to help cut back on heat soak?
RIP 10-07- 1984 Toyota Tercel SR5 4wd Wagen 6 speed

RIP 04-05- 1986 Toyota Tercel SR5 4wd Wagen 6 speed

1st Terc- 1987 Tercel SR5 4wd Wagon 6-speed, Sadly cubed

1985 Tercel Standard 4wd Wagon w/ 3-speed auto, Living a happy life in Boulder last I knew
Typrus
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Re: another weber install (3A-KT)

Post by Typrus »

http://cgi.ebay.com/ebaymotors/_Car-Tru ... 06.c0.m245

Suggests the GT-25 is one half of the equation in a twin-turbo 3.0L V-6.

So. 1.5L I-3 is it's home engine.
Not to mention with an off-base firing order, so uneven exhaust pulses.

So, 1 extra cylinder + even spread of exhaust pulses= smoother spool thus faster spool? Thus the 1.5 PSI at just under 2k? 3PSI giving good benefits up to 7k... Big factor here being flow perhaps?

6 PSI starting in at clutch slip? Though it is essentially impossible to say there is a concrete factor for calculating power increases, one could say that assuming 62HP at 14.7PSI (1 bar) that there might be 87.3HP at 5200RPM. Then, because of the increased fuel and airflow above that, it would be safe to assume that the power curve continues to climb above the factory 5200RPM peak. Extrapolating it out, at 7000RPM we could be seeing 130HP according to one calculator thingy that compensated for air temp, bore, stroke, number of cylinders, vol efficiency and turbine efficiency using a generic turbine flow chart.
80% engine vol efficiency and 80% turbine efficiency
70F ambient temp
3.05 bore x 3.03 stroke
6PSI boost
7000RPM
Est. 137BHP est 103ft/lb

Lets make it .001 boost.

LOL... It claims 110HP. LOL.... Maybe my VE is a bit high.... Lets try 65%.
Well, 65% with all the above only .001PSI boost yields an est 66HP/67ft-lb@5200RPM, 89/67@7000. Lets bump it to 6PSI.
65% @ 6PSI 83/84-BHP/TQ @ 5200RPM.
65% @ 6PSI 7000RPM- 112/84 BHP/TQ

Shall we dare go to 12 PSI? We are 9.0:1... THINK THE HEAD CAN HANDLE IT????

65% @ 12PSI 5200RPM- 98/99 BHP/TQ
65% @ 12PSI 7000RPM- 132/99 BHP/TQ

Albeit we could likely bump up the VE of our engine relatively easily, reinforce the block (there is some space in the bottom for HARD-BLOK epoxy-iron block concrete) maybe get our head to stay seated as high as 14PSI... Throw a 4AGE bottom end under our 3AC head... Nice non-twist forged crank, forged pistons... sweet rods... Ah, but then the bore is 3.19!!

Assuming everything else same, the extra bore (from 3.05 to 3.19) is good for
@ 12PSI 5200RPM- 107/108 BHP/TQ
@ 12PSI 7000RPM- 145/108 BHP/TQ

Get that head nice and segsay... We'll call her 72% VE!

119/120 BHP/TQ @ 5200
160/120 BHP/TQ @ 7000


Man this Ray Hall calculator sure predicts a flat torque curve for us...


BTW, I just realized that this calculator uses Celcius for the ambient temp...

Burn baby burn! (disco inferno!) no... wait...

But apparently adjusting to 21.1C made no difference. Yay for unrealism!


I'm tired! And Rambling! lol... Bed time...

130HP+2300lb car= WEEE!!! As good of grunt as a
RIP 10-07- 1984 Toyota Tercel SR5 4wd Wagen 6 speed

RIP 04-05- 1986 Toyota Tercel SR5 4wd Wagen 6 speed

1st Terc- 1987 Tercel SR5 4wd Wagon 6-speed, Sadly cubed

1985 Tercel Standard 4wd Wagon w/ 3-speed auto, Living a happy life in Boulder last I knew
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ARCHINSTL
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Re: another weber install (3A-KT)

Post by ARCHINSTL »

Why bother with all of this work?
There is that purty (perty in CO :) ) red engine in that other thread that makes 182 HP sans dramatic add-ons...
Tom M.
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Typrus
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Re: another weber install (3A-KT)

Post by Typrus »

Meh, thats all stuff plugged into a calculator with a tired guy plugging in random numbers with little real world basis for accuracy.

I get the feeling that if handled right, with the right cam, right porting of the head and intake manifold, that the improvement would be dramatically increased.
RIP 10-07- 1984 Toyota Tercel SR5 4wd Wagen 6 speed

RIP 04-05- 1986 Toyota Tercel SR5 4wd Wagen 6 speed

1st Terc- 1987 Tercel SR5 4wd Wagon 6-speed, Sadly cubed

1985 Tercel Standard 4wd Wagon w/ 3-speed auto, Living a happy life in Boulder last I knew
SR5 Tercelerator
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Re: another weber install (3A-KT)

Post by SR5 Tercelerator »

What do you guys think about using a turbo from an older RX7? (we've got one) I've always wanted a car with boost...and one this ugly will be nothing but fun!


But where is the thread about the red engine that rocks? Is that a 7afe swap? 180 HP swapped stock or built up?
Typrus
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Re: another weber install (3A-KT)

Post by Typrus »

http://www.cardomain.com/ride/708655

I dunno how much I believe that... Thats over 100HP/liter on a SOHC architecture with no boost or bottled boost... Sounds a bit high....
Albeit, crank and rods are something we can steal from a 4AGE. Heck, we can pilfer a whole 4AGE bottom end and have a bullet-proof build done. As for the 4AC/3AC head architecture with "dome" pistons and oversized valves... We have room for all of maybe 2 intake valves next to each other with some hardcore unshrouding?
I guess everything but the valves and pistons sounds realistic. However, with money, the pistons could be made.


But thats a different topic.
RIP 10-07- 1984 Toyota Tercel SR5 4wd Wagen 6 speed

RIP 04-05- 1986 Toyota Tercel SR5 4wd Wagen 6 speed

1st Terc- 1987 Tercel SR5 4wd Wagon 6-speed, Sadly cubed

1985 Tercel Standard 4wd Wagon w/ 3-speed auto, Living a happy life in Boulder last I knew
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