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Small Block tuning and options

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Right then, a bit more power eh?

Sounds reasonable enough!

There's 2 options really. Option 1 tune the engine. Option 2 Replace the engine.

According to Wiki mk1 golfs had 59 horses out the factory.Lets start here and we'll talk about gear boxes in a bit.

Option 1 - Tuning Many options here but the simplest and most effective bang for buck is to change the carb. 3 options really.1, Easiest is to go with a twin choke Weber Single Carb conversion. Bigger ports mean more air and fuel = more power.  This would probably fit but talk to them , bolts straight onto the inlet and comes with everything you need to make it work except an air filter. Get a decent one and you'll see some gainshttps://www.dellorto.co.uk/shop/weber-carburettors-parts/weber-twin-barrel-carburettors/dmtl-carburettors/vw-golf-1-3-weber-replacement-carb/Should see around 10 more bhp but will improve torque and throttle response and make the car feel a lot more alive. Also easy to install and to set up properly. Any 'old school' garage should be able to set it up for you.

2, Twin Carbs - Need a manifold (which can be quite hard to find used) and some carbs. Manifold is here https://www.dellorto.co.uk/shop/car-accessories/inlet-manifolds-and-fittings/inlet-manifolds/vw-pologolf-1-1-1-3l-to-suit-twin-dhladcoe-40mm Simply bolt on with a new inlet gasket and then you can use either Dellorto DHLA or Weber DCOE carbs. (I prefer Dellorto personally). Very expensive to buy new and if you buy second hand will require re-build and probably new jets etc to match the requirements for your engine.https://www.ebay.co.uk/itm/DELLORTO-DHLA-40-G-TWIN-CARBURETORS-VERGASER-FIAT-ABARTH-ALFA-FORD/292941495889?hash=item4434ac7e51:g:gVcAAOSwSxVcUxYv   https://www.ebay.co.uk/itm/twin-40-carbs-Dcoe-Weber-With-Linkage-Short-Trumpets/133087567943?hash=item1efca32047:g:VcoAAOSwAUJdBoCI&frcectupt=trueHave a look through Euro carb website to assess the cost of the re-build kits https://www.dellorto.co.uk
 You'll need a linkage for the carbs, a linkage to the carbs (throttle cable linkage) and some fuel pipe and other bits and bobs. Filters are optional. I don't run any but others do.You can use the mechanical pump on the engine block and simply link the carbs to this. Works fine and produces enough flow at the correct pressure to run twin carbs with no problems. You DON'T need regulators, filter kings and pressure regulators if you use the mechanical pump. If you want to go down the route of electric pumps then you can put one in the engine bay and then you'll need a pressure regulator.Ideally these will need setting up on a rolling road.As it's been done many times in the past it is easy to buy all the correct internals for the carbs from a stockist.

Option 3 - Bike Carbs.First off you'll need a manifold. You can buy an inlet manifold gasket, get it laser cut and weld on some some tubes at the angles required to meet the carbs and away you go.Or you can buy a DIY kit like this https://www.ebay.co.uk/itm/POLO-8v-1-3-1-4-DIY-BIKE-CARB-THROTTLE-BODIES-INLET-MANIFOLD-KIT-38mm-PIPES/151946458624?fits=Car+Make%3AVW&hash=item2360b6f600:g:6ioAAOSwaA5Wk3rE&frcectupt=true  or you can go to ST Engineering and they'll make you one https://www.ebay.co.uk/itm/VW-Polo-1-4-16v-Lupo-GTI-AFH-Manifold-for-CBR600-Carburettors-Bike-Carbs/331904652186?hash=item4d470f139a:g:oxkAAOSwygJXgWzH  The one linked doesn't fit the engine in question so don't buy it, but they do make them to order!Next some carbs. You'll need to choose the carbs first then get the manifold made to fit the carbs as they have different port sizes and spacings depending on carbs.
I use CBR 600 carbs but know of people using Yamaha 1100 carbs. the biggest problem you will find is getting someone to set them up for you. They have to be balanced to ensure the same amount of fuel and air is going in and then they have to have the jets drilled out in increments to get the correct amount of fuel into the engine.
Fueling - You need a bike carb pump to pump fuel at the correct pressure to the carbs. All bike carbs seem to use the same pressure so any bike carb pump will work. Don't buy the £20 ones on ebay! Go for a second hand original equipment one. Trust me I know!!!!!!!!!! They need to be mounted close to the tank as possible as they are a 'push' pump not a 'pull' pump. Luckily there is room under the drivers side right at then back where the GTI has a pump/filter mounted. It's tight be do-able.
Pros - Bike carbs are cheap compared to Twin Carbs. Pumps are cheap and plentiful
Cons - You need to find someone to set them up which is difficult. Manifolds will probably need to be custom made = expensive.


So that's the air and fuel in. To get it back out is the next step.

ExhaustYou'll need a 4 branch manifold.  https://www.ebay.co.uk/itm/STAINLESS-4-2-1-DECAT-DE-CAT-EXHAUST-MANIFOLD-FOR-VW-POLO-1-0-1-1-1-3-86C-6N/351812634225?fits=Car+Make%3AVW%7CCars+Type%3A1.3&hash=item51e9aac671:g:QqMAAOSwgSpb1z3f   You'l then need an exhaust. Don't go too big as it won't fit and won't create the back pressure you need.We could into Cams etc but I'm not going to. With Carbs and an exhaust you will see between 90 and 100 bhp, more torque, lovely noise and better response. The MPG should remain around the same too.Check out Clubpolo and the Polo Facebook pages for more info as it's a Polo engine.

My Derby (mk1 polo saloon) on twin carbs is here: https://www.tapatalk.com/groups/mk1poloclub/it-ain-39-t-easy-bein-green-t1073.html  or herehttp://forum.retro-rides.org/thread/67193/1980-vw-derby-gls?page=1  as since Photobucket went mad stuff has disappeared from the mk1polo website.
Click on the Mynx thread in my signature for stuff on bike carbs.


Engine Swaps.You can use anything from the early Polo's   https://en.wikipedia.org/wiki/Volkswagen_Polo upto and including 'Third Generation' as long as it's the same size and shape with the same mounting points. Avoid the diesels though as I believe the engine mounts will be different. Later engines may fit but I have no knowledge of this.

Polo GT engines are sought after and the price is getting silly,the G40 is a supercharged version of the 1.3 8v engine and are very expensive (2k and upwards) the 1.4 AFH twin cam 16v is the same and the 1.6 twin cam 16v is also getting mad. People use a 1.4 top end mated to a 1.6 bottom end for top BHP.
 I bought 2 AFH 16v engines and both were rubbish. I had the 'best' re-built using bits from each and new bits as required. With a re-bore,  a head skim, all new pistons, rings, bearings, seals, valves, valve springs and a bit of custom work to the head it cost me about £1600. Just as an idea of cost. (makes sticking with the current engine and tuning it seem cheap now right?!)
With it running bike carbs and a good exhaust manifold and after market exhaust the rolling road said I had 146bhp at the crank. Not bad for a 100 bhp engine from the factory.

If you go with an injected engine you can either ship across all the injection stuff or you can chuck carbs on it (see above).I'd suggest that if going with an engine swap you buy a polo and take it all out and move it over. Plus that way you will make sure the car runs ok before buying an engine that needs a re-build. Probably cheaper too tbh. A polo can be had for £400 - £600 quid and a scrap shell is worth around £100 plus whatever you get for selling off the rest of the stuff.

Gearboxes.

Hmmmmmmm.

All VW gearboxes are rubbish. Lets get that out of the way to start with.

Small block 5 speed gearboxes are really rubbish.

They are made of chocolate and glass! When you chuck larger bhp's through them they really don't like it.

I have one (currently in the car) that has a sticky first, crunches into 2nd, hates going into reverse and has just decided to eat it's own diff. I have a second one and that seemed ok until i used it and the only gear it would go into was third once it had been running for 5 minutes.

Lets ask a really basic question. Why do we want 5 gears? Is it for cruising economy? is it so we can say 'it's a small block with a 5 speed box' ? or is it so we have an extra gear to play with? or is it so we can go faster?

Mynx will not pull in 5th at all. All the power is top end therefore I have no torque low down at 2500 revs due to the way the engine works and is tuned. I live in Cornwall and our main road out of Cornwall is the A30 and is 100 miles from me to Exeter and the beginning of the M5. It is also known as being extremely hilly with some of the biggest elevation changes over a short distance in the country. Scotland and Wales have bigger changes but not over 100 miles.
As such in Mynx I have to change gear a lot to get up the hills. This doesn't make for relaxed cruising! It does depend on the ratios in the gearbox however.
VW made 5 speed boxes for 1 litre cars that have different ratios to the bigger 1.4 cars. I presume due to torque differences in the engines.
The current gearbox does about 2.2k revs at 70mph. The one that sticks in 3rd does about 3k at 70mph the same as 4th in my box! The current box also allows for reaching close to 70mph in 2nd!!!!!!!!!
Great for long acceleration but rubbish for throwing her along B roads at 40 -60 mph. Where I would want to be using 2nd and 3rd I'm trying to use 2nd and 1st!!!! That doesn't work. 2nd is too long.

It's well known that 5 speed boxes are rubbish and all the good ones from low mileage cars are gone. So chances are you looking at re-building it. I've been quoted around £400 for a re-build.
So if your 4 speed is ok, ask yourself do I really need a 5 speed?
These engines are quite happy at 3.5k - 4k revs for long periods. They were designed to do it as the early cars never had 5 speed boxes. Fuel economy? How long do you actually spend on a motorway at 70mph vs how much running around do you do at 30 to 60 mph?

My Derby and Mynx both get around 35 miles per gallon on a run. Derby 1272cc with twin carbs (approx 90bhp?) and a 4 speed box and Mynx with a 1400cc twin cam 16v on bike carbs (146bhp) with a 5 speed box. Very little in it at all. The last time Mynx did a run she wouldn't stay in 5th so I ended up running in 4th all the way to the AGM and back again (around 600 miles) and she still returned about 35mpg!

Here's a list of VW gearboxes https://www.proxyparts.com/wiki/gearbox-codes/make/volkswagen/model/polo/

and here's some threads on polo gearboxes https://uk-polos.net/viewtopic.php?t=38330

Lots of info out there!Give me a yell if I can help anyone with something specific

Cheers

Ian

Cornish Host.
1980 VW Derby
Clive the Cabby
Ujum the Invisible
Mynx the  Tintop

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Hi mate, great info on there.
Just a quick question, would the manifold listed on eBay  for the Polo fit a mk1 golf 1.3 engine?
The manifold mounting flange seems to have a second row of bolts on the left hand side.
Seems different to mine.
Anyone on here fitted one?.

Thanks in advance?

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Tuning a Piano and Guitar is a whole lot easier trying to get more HP out of a 1.3…..

I mean look at the hp of the average Sport Car of the 50/60 imports over here in the US… 948 to 1100 1200 cc British Leyland lines… 40-56 hp…. I was lucky to pedal my Frog-eye to get over 55mph…. 70 going down a really really steep Hill…. :)

"Any one can tune a Guitar, or Car, but no one can tune a fish?"

What do Divorces, Great Coffee, and Car Electrics all have in common?

They all start with GOOD Grounds.

Where are my DIY Links?

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Thanks for that Briano1234

I have managed to get a tune out of a fish once. It was a Bass.  :lol:

Anyhoo.

Andyp-75

Yep a polo manifold will fit a golf 1.3 as they were the same engine. However you need an early polo one. Upto about 1985 or so.

If you're referring to the one above in my meandering post, then yes, it should fit. Do you have your engine code?

Ian

Cornish Host.
1980 VW Derby
Clive the Cabby
Ujum the Invisible
Mynx the  Tintop

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Hi
What would your thoughts be on the 4-2-1 manifold and bike carbs on the1100 golf engine?

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Mattlong said

Hi
What would your thoughts be on the 4-2-1 manifold and bike carbs on the1100 golf engine?



It depends on your goals for the car of course. It will make more power, but don't expect miracles. Since they're mechanical, you could put a monster cam in it too. Shave the head for more compression… But I can't image you'd be able to get more than 80 HP out of it reliably. It sure would make good noises. I'd suggest a 5 speed gearbox conversion as well.

See my videos, Tom AFH

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nedrager said

Mattlong said

Hi
What would your thoughts be on the 4-2-1 manifold and bike carbs on the1100 golf engine?



It depends on your goals for the car of course. It will make more power, but don't expect miracles. Since they're mechanical, you could put a monster cam in it too. Shave the head for more compression… But I can't image you'd be able to get more than 80 HP out of it reliably. It sure would make good noises. I'd suggest a 5 speed gearbox conversion as well.



Thanks for your reply, are there cams for 1.1's or are they coming out of other engines?
I'm not looking for huge increases, 70 would be lovely, to  give it a bit of extra pep.

Matt

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Really interesting post, thoroughly enjoyed the read. I had a mk2 1.3 breadvan that was on 36k and was wrote off, I the cars at a breakers with the engine and four speed gearbox intact, might be worth getting it and rebuilding them for my mk1. my mk1 is a 1.1 with only 59k on the clock so not sure if an engine swap is a good idea but it could be good to have the engine and gearbox from my old breadvan as a spare incase anything goes wrong

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Deffo, why not?

More cc's more power! But it's more the torque that makes the difference.

Ian

Cornish Host.
1980 VW Derby
Clive the Cabby
Ujum the Invisible
Mynx the  Tintop
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