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MGB MGB 4 cylinder conversion

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chucknorris255

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So I know everyone has a different opinion about this, and I have read lots of posts and even more posts but still havent found an answer. I was wanting to put a reliable 4 cylinder in my 73 mgb this Spring with minimum effort. What is the easiest conversion.

Thanks!!
John
 
John, whats wrong with the original?
Those things are nearly bulletproof.
Or do you just want to upgrade to something a bit more modern?
Jeff
 
Jeff,
The current engine is alright, its just all the accessories to the engine are in pretty poor shape. I use to drive it as a daily driver, but since then the carbs have given me trouble, the ignition system. Honestly, since the car is not in original shape, i was looking for convience of a modern motor to start, especially when it is cold outside.
 
John, there are many folks here that could give you a better idea than I. I've seen Chevy V-6's as a transplant, but don't know the particulars.
Perhaps Tony will be along shortly to offer his wisdom.
Jeff
 
Just my personal opinion.....its hard to beat the original engine built properly with a good set of HIF-4's or HIF-6's!!

So, you put a VETEC in it, or a rotary, or something else unusual; so.....

Why not rip the original out & take it to the max! Have Hap build a set of HIF-4's or HIF-6's; gear reduction starter, upgraded modern alternator & fuse block, line over-bored to about 40, hot cam, flow the head w/bigger valves & modified chambers, roller rockers, PECO header w/custom exhaust, aluminum fly, distributorless ignition, aluminum 4-core radiator, 5-speed trans - all the bells & whistles.

Add to it Hawke Engineering coilover front suspension, carbon fiber rear springs w/anti-tramps & rear disc brakes.....

& while you're at it, doll up the entire engine compartment with lots of chrome & staimless....
 
On the Spridgets the Datsun 210 engine works and has about the same power and weight as the "B" engine, it is moderately current and easy to get parts for. I have never heard of anyone putting one in but it should work fine and there are 5-speeds for them too.
Bill
 
You will spend far less time and money rebuilding the existing engine and all of its ancillaries than you would doing an engine swap. Even when the swap is done, there will be numerous small (hopefully) issues to work out. I agree with what has been said of the ruggedness of the B-Series lump. It isn't the lightest, coolest or quickest engine you could put in, but are those things really why you bought a B? Heck, if you just want modern convenience and all out performance at a low price, the Miata is pretty hard to beat! That all said, it's your car and if you want to put another engine in it then by all means feel free to do so. Just be sure of what you're getting into before proceeding.
 
I'll have to agree that these engines are reliable when cared for and driven as they should be, always.
 
Go with an aluminium head, Pertronix ignition, upgraded alternator, and (gasp) a Weber DGV carb and you'll be back to a reliable dailey driver. Weber haters insert comments here().
 
wdp said:
Go with an aluminium head, Pertronix ignition, upgraded alternator, and (gasp) a Weber DGV carb and you'll be back to a reliable dailey driver. Weber haters insert comments here().
Click to expand...

This is a Red Line Weber unit. It lists for around $535.00. It can be had at Autohaus Arizona for $355.00 + tax. For the same price or less, you can have your SUs rebuilt, skip the modifications and get far better performance.
k050.jpg

I personally would only go to the trouble of installing this carb on a late model car that came with a single carb. Not a pair of SUs! The single carb models have been known to be very contankerous at times. The DVG has a habit of hesitating when you take off from a standstill and I find that they don't give the same fuel economy as a pair of SUs. If the hesitation and less fuel economy doesn't bother you, go for it! But, don't confuse the DVG with the Weber side draft DCOE carbs. There's no comparison. JMHO. PJ
 
Hello John. The original is as reliable as any. Another plus is it fits the hole already.
 
It's your car, but if it were mine, I'd stick with the stock 1800cc engine. It's a solid unit and sounds better than almost any other engine I can think of.

The twin SU carbs on your car are very, very simple to rebuild and adjust....my lawn mower carb is more complicated.
 
If you're gonna stick any kind of Weber in the engine compartment, you minght as well stuff a Ford VETEC engine in it!

I'll take a good running set of HIF-4's any day & blow the doors off a Weber-equipped car (everything else in the engine being the same)! The dual OE carbs are still doing their thing while the Weber is 'hiccupping' at about 2,000-2,500rpm...& no matter what you do, you can't get rid of that slight hesitation! Just my personal opinion based on a few Webers I've taken off & thrown in the trash!
 
I am in total agreement with Tony. I had a weber on my '80B when i bought it,,,, I immediately switched to twin SU's,,, and I'd never go back.

The weber ran like junk. The hesitation was horrible. And just like Tony,, my setup will outrun and out-perform a weber any day of the week.

Once I figured out,,, if it ain't broke don't fix it,,, and stopped touching the SU's,,,,, they require no tweeking.
 
The aluminum head Nissan 1500 (A15) is lighter and more powerful than the stock B1800. There are a lot of accessories available for them, including twin SU carbs and of course twin side draft webers and other performances enhancers.
Think of having one intake barrel per cylinder.
Also as Bill mentioned you should be able to locate one with a 5 speed already attached. You can also go with a more modern version of this and gain even more, but at increased cost. The group over at datsun1200.com can give you lots of ideas and access to parts as well.

Of course, you can also do this with your 1800 and it will enjoy greater power and decreased economy. Matched with a good electronic ignition and a freer flowing exhaust it could be great.

Personally I think putting a pair of fresher (and maybe larger) SU's on there and tuning it would be enough to keep me happy. Maybe get a book or two and learn how to freshen up the carb yourself. There are a variety of parts & pieces available.

I remember 25+ years ago I used to experiment with the shape of my jet needles, having a supply of them I shaped them and then installed and ran them, shaped some more. Sometimes I'd have to throw them out and start over, sometimes I came up with a shape that pleased me for one reason or another. I also owned a Volvo 122 with twin SU's at the time so I was hip deep in carb parts and had no life at all except my cars.

This is a nice page about the SU - from a Rover but it's still an HS6. Nice drawings & explanations, there are a lot of this on the net - a search for "SU carburetor diagram" turns up a lot of hits.

https://roversd1.info/2600/carburetor.html
 
The ONLY engine swap that makes any sense in a B is this one:

bill2.jpg
 
/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif HALLELUJIAH, Brudda!!!!
 
John,

So, OK... I will freely admit that I am an OC, AR, purist...Not even replacing the 1498cc in my A with an 1800cc... the list goes on....

However, in your statement <div class="ubbcode-block"><div class="ubbcode-header">Quote:]reliable 4 cylinder in my 73 mgb this Spring with <u>minimum</u> effort [/QUOTE] the operative word being MINIMUM...

A well rebuilt twin SU 1800 is reliable and perky enough for all but the speed junkies....

My recommendation... clean up the original, leave the twin SUs in place and drive it till the wheels fall off...

My two cents worth.. /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
 
Wow,

A Corvette buster if ever there was one.... /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
davester, that's purdy!! /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
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