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Discussion Starter · #1 ·
In process of rebuilding a B20F to put in my 122. I plan to use my SUs and need to plug the FI holes. I have heard that freeze plugs can be used...anyone know what size?

Also will need an 8-bolt flywheel if you got one layin' around.
 

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In process of rebuilding a B20F to put in my 122. I plan to use my SUs and need to plug the FI holes. I have heard that freeze plugs can be used...anyone know what size?

Also will need an 8-bolt flywheel if you got one layin' around.
Will the SUs fit with the injectors left in place?

George Dill
 

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Nickels with o-rings under them also work believe it or not, but you gotta make some kind of toe clamp to hold them in.
 

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I have been accused too many times of doing things half ass, but my guess is that RTV will be enough to hold anything, since you are having vacuum you are trying to seal against. Nickel sounds too expensive :), I would try pennies first! Or a short bolt that just gets through the hole, with lots of RTV everywhere! Why leave the injectors there? Sell them to somebody that plans to use them as injectors instead of hole plugs.
 

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Discussion Starter · #6 ·
7/8" domed freeze plugs, the type you expand by flattening, like all the others on a B20.
Thanks Phil...I'll source these, as long as less than a nickel a piece!
 

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Discussion Starter · #8 ·
So the B20 has 120K on it and appears in fairly good shape. I just plan on a cursory cleanup, replace gaskets and stick it in. I'm not looking for a 160hp performance engine, just reliable daily driver with maybe a little more power than my B18. Given a limited budget, what are things I should look for and should replace? Does this engine have hardened valves for unleaded gas?
 

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Yes, it's new enough to have exhaust seat inserts from the factory. And it's low compression, so regular unleaded will be fine -- no advantage to using premium.

Check the needles in the SU carbs -- you want KD needles for that engine.
 

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if you want more power, you should consider replacing the head gasket with a lower thickness and bring compression ratio to B20B standards. You may have to use 89 octane gas, but the added power (possibly close to 10%) may be worthwhile, not to mention a bit better fuel economy.

And if you use the water injection system, you may be able to get the engine happy with the 87 octane fuel too! ;)
 

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I have an 8 bolt flywheel thet came out of a boat of all things. As far as I can tell it's the same as one for a manual transmision. The boat drive uses a piece of sheet metal that bolts on the flywheel like a pressure plate and has splines in it like a clutch plate.

I'd give it to you but the the thing was so rusted together that I had to resort to a sledge hammer to get the drive off the motor and ended up breaking a tooth on the ring gear.
I don't know what kind of boat it came out of or how common thay are but it would be one place to look anyway.
 

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Discussion Starter · #12 · (Edited)
OKay...getting closer...I should receive the head back from the machine shop early next week and begin reassembly. I intended to use the SUs from B18 but I am currently having issues with my carbs and I'm not sure I want to continue using these if they remain problematic (or maybe it's just my lack of ability to successfully adjust, tune, and maintain them). My buddy has recommended putting the LH 2.2 FI system from a 85-88 240 onto the B20F.

Does anyone have experience with this? What all would I need for conversion? FI parts and wiring harness, high pressure fuel pump, injectors and temp sensor? Would I need an in-tank fuel pump?
 

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I never had serious problems with them once I learned how to set them up, and I had SUs from a '56 A-H 100/4 up to '74 140s. The only problem I had with CD carbs was that bugger of a Stromberg in an '82 245. There is a web site that has all the info you need on SUs, but I need to search for it, or maybe someone else here knows where to find it? As for the swap to LH-2.2, do a search on Turbobricks as there are others there who have done it, but be wary of the stock 85-87 biodegradable harnesses and make sure that you get the later replacements.
 

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Generally speaking, if you are willing to tolerate your engine not working in "perfect tune", i.e. not perfect stoichiometric mixture, and not always instant cold starts or hot starts, etc, and/or willing to be tinkering occasionally with adjustments, the carburetors may be preferable over an unknown injection system. The carburetors will almost always get you home. The FI wither works "perfectly", or yo call the tow truck. Once you understand how the SU's work, you will not have that much trouble with them. I think that their reputation came from people not putting the effort to understand how they work.
 

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If you are new with SUs you should probably get someone who KNOWS them to teach you about them. There is quite a bit to learn and much of it is not intuitive. Edit: Seeing your location, there are quite a few guys in the Pac NW that know them well, from IPD to Rhys Kent at Island Automotion in BC.
But if they are in good shape and properly set up, they are sweet.
 

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Discussion Starter · #17 ·
Skip the FI but get the SU's fully rebuilt then return here for tune-up details.

George Dill
So my B18 was progressively running worse over the last 3 weeks...missing, no power, black exhaust and lotsa gas fumes in the cabin. After watching countless videos on You-tube concerning SU tuning (where it seems so simple and the guys can dial'em in under 5 minutes) and pouring over alot of the SU tuning documents that can be found on various sites (links often supplied by Mr. Dill and others), I spent the weekend trying to tune the carbs: Videos seem simple enough, the documents are straightforward, and I'm beginning to understand the theory and simplistic design of the SU.

So I dive in, follow the guides and find that my back jet is not secure, ie. the locking nut is not secure and the entire jet is loose. Tighten, syncronise, adjust mixture and idle, everything seems fine. Put my air filters on, test drive and still just as bad. Redo everything, this time being careful to mark my jet adjustment nuts so I can keep track of the 'flats' that I adjust, check my float bowls, clean the hell out of everything...sounds perfect...slap it back together..test drive..WTF!!!..still bad...How can I be such an IDIOT and not do this just like the videos

Limp to parts store...get new air filters...running like a sewing machine!! (not quite, but near perfect)

Guess I could have saved myself alot of trouble had I just recognized the symptoms and put new filters in, but never would have become so intimately involved with my SUs....confident now that I can synchro, set mixture, etc., but you can bet your a!! that, in the future, at the first sign of sputtering I'm sure gonna swap-out those filters.

Short-story-long: maybe I'll just keep those SUs instead of FI
 

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So my B18 was progressively running worse over the last 3 weeks...missing, no power, black exhaust and lotsa gas fumes in the cabin. After watching countless videos on You-tube concerning SU tuning (where it seems so simple and the guys can dial'em in under 5 minutes) and pouring over alot of the SU tuning documents that can be found on various sites (links often supplied by Mr. Dill and others), I spent the weekend trying to tune the carbs: Videos seem simple enough, the documents are straightforward, and I'm beginning to understand the theory and simplistic design of the SU.

So I dive in, follow the guides and find that my back jet is not secure, ie. the locking nut is not secure and the entire jet is loose. Tighten, syncronise, adjust mixture and idle, everything seems fine. Put my air filters on, test drive and still just as bad. Redo everything, this time being careful to mark my jet adjustment nuts so I can keep track of the 'flats' that I adjust, check my float bowls, clean the hell out of everything...sounds perfect...slap it back together..test drive..WTF!!!..still bad...How can I be such an IDIOT and not do this just like the videos

Limp to parts store...get new air filters...running like a sewing machine!! (not quite, but near perfect)

Guess I could have saved myself alot of trouble had I just recognized the symptoms and put new filters in, but never would have become so intimately involved with my SUs....confident now that I can synchro, set mixture, etc., but you can bet your a!! that, in the future, at the first sign of sputtering I'm sure gonna swap-out those filters.

Short-story-long: maybe I'll just keep those SUs instead of FI
Good work - thanks for sharing.

Some thoughts...

Before final SU tune be absolutely certain that ignition timing/system/distributor, valve adjustment, PCV system, choke system, fuel system, cooling system (correct thermostat?), fan belt(s) adjustment, battery, charging system, etc. are in order.

Final tune the carbs with the air filters removed. If the tune goes bad when the filters go on replace the filters.

Tune a fully-warmed engine but not hot. If you can smell "heat" the engine is too hot to tune.

Once the test drive shows good tune start challenging the setup by leaning both carbs three flats then test drive again. Repeat until performance is lessened, you hear pinging and/or you experience stumbling/ hard start, etc. then go back three flats richer, test drive and three more richer until optimum performance is obtained for your driving style and power needs.

Running too-rich carbs is bad news.

George Dill
 

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Discussion Starter · #19 ·
BTW---the air filters in question had only been in car for 6 months...so really didn't suspect them, at first.
 

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Just get some K&N filters and forget about it! I've got this same motor bored .015 over getting ready to go in my 122 as well!
 
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