2 litre 8v conversion - various tuning questions.

Hi guys,

I have done my research quite thoroughly for the popular 8v conversion, but still have some questions.
I have found a good healthy AGG-engine with low mileage and started to disassemble it.

The plan is to run it with 2 x 45 mm Weber DCOE's, a new camshaft and some other modifications.
I already have the throttle linkage, DCOE manifold, 4-1 stainless steel manifold and Jetex 2,5" from manifold and back.

The car is a 1,5 litre, so the engine mounts should be OK - right? And the 020-gearbox should fit with the AGG-clutch?
I will keep the gearbox, because it is a 4+E (5 speed) and in very nice condition.

The head is tricky as I would like to keep the AGG-one and the 1,5 is not usable. I don't really want to have to buy a new one.
But it depends on what I would gain from buying a PF head and install this instead? (in terms of HP and performance).

Shopping list:
- AGG Engine (Done)
- Weber DCOE/manifold, throttle linkage, soft mounts, airhorns, airfilters (Already bought).
- Manifold and exhaust (Already bought)
- Camshaft - Techtonics 276
- Adjustable camshaft gear - Techtonics
- TSR dizzy kit with blanking plate for crankcase breather
- Steel headgasket from ABF, gasket set and camshaft seal
- New sparkplugs and leads
- New timing belt kit and waterpump
- New engine mounts (old must be worn).
- New lifters
- Fuelpressure regulator
- Paint etc to finish it off
- Oil, coolant etc.
- Stretch bolts for head

Questions:
- Is the engine mounts the same as in my 1,5 litre JB-engine? I would think so.
- What is the powergain from using af PF instead of the existing AGG 2 litre head? (as I do not really want to have to buy another head).
- How can I tell whether my AGG is an OBD1 or OBD2? The engine has "95" stamped in it so I guess, that it is OBD1.
- Which clutch should I use? The AGG one or the 1,5 JB?
- Any inputs as to the TT 276 cam? Seems that this is an overall good choice.

 

First I am not an expert engine builder/tuner, but I don't like twin sidedraughts on these 8v engines. There is very little room to fit them with a decent intake runner length, they also sit in what is probably the hottest part of the engine bay. Thirdly I think you would have to spend a fortune on the cyl head to make it need the flow capabilities of twin 45,s. However its your car and its best to actually do what you want to do instead of being held back by other opinions.

you cant use the AGG head with carbs as it has large odd shaped ports for the injector cut outs, (unless your manifold takes this into account) unlike a mk1 or 2 GTi head which has injector holes you can plug. dont know what a PF head is. all i can see is its a low power USA head
the ungine mount off a JB 1.5 will go on, the AGG is a tall block so you may need exhaust alteration.
odb1 was twin connectors and odb2 is the shape connector in most modern VW's.
use a new AGG clutch and its flywheel
 

abfmk1 said

First I am not an expert engine builder/tuner, but I don't like twin sidedraughts on these 8v engines. There is very little room to fit them with a decent intake runner length, they also sit in what is probably the hottest part of the engine bay. Thirdly I think you would have to spend a fortune on the cyl head to make it need the flow capabilities of twin 45,s. However its your car and its best to actually do what you want to do instead of being held back by other opinions.

Hi,

Thank you for the post.

I have decided to use the 2 litre AGG engine and also decided for an 8v project with counter-flow head.

I have a 2 litre 16V 9A engine already, so I want to try a different route this time Otherwise I would have loved to try out a modified ABF.

I have the sidedraughts fitted on the 1,5 JB and it will accommodate at least 1,5" runners or airhorns depending on your airfilter setup. I have used modified airfilter socks from Pipercross, that takes up no space at all. Agreed - it is not ideal compared to a crossflow head, but there is plenty of space for it to work.

Any comments as to which head to use?

volkswarren said

you cant use the AGG head with carbs as it has large odd shaped ports for the injector cut outs, (unless your manifold takes this into account) unlike a mk1 or 2 GTi head which has injector holes you can plug. dont know what a PF head is. all i can see is its a low power USA head
the ungine mount off a JB 1.5 will go on, the AGG is a tall block so you may need exhaust alteration.
odb1 was twin connectors and odb2 is the shape connector in most modern VW's.
use a new AGG clutch and its flywheel
 

Hi.

Thanks for the post!

Haven't really tested out the intake-manifold to the AGG head, as the old engine is still in the car with the sidedraughts fitted. Want to try this out soon.

The PF engine is the eurospec 1,8 litre 8v GTI with 107 HP, from the Golf Mk2, From what I have read this is similar to a DX head, that flows better than the 2 litre AGG.

Can anyone tell me which counter-flow 8v heads that flows best for an AGG-engine?  Then I will find and buy one of these instead of the AGG-head.

The question as to OBD1 and OBD2 is because the OBD1 (early AGG engines) has stronger crank and forged pistons, as well as stronger head with stronger valve springs.

Very good to have confirmed the enginemounts and clutch/flywheel setup. I hope that the 4-1 manifold will clear the steering rack.

Thanks!

Actually sorry you will need a 1.8 GTI clutch the Agg box is the same as a 16v mk 2 so has the larger centre shaft, your mk1 box won't, but the mk1 dx clutch is the same size but small centre.

volkswarren said

Actually sorry you will need a 1.8 GTI clutch the Agg box is the same as a 16v mk 2 so has the larger centre shaft, your mk1 box won't, but the mk1 dx clutch is the same size but small centre.

OK - thanks.

That would be the 210mm one with small centre shaft. Luckily not really what messes up the budget

the mk2 and mk3 gti heads flow the same or close enough, its a myth that the mk3 heads dont flow as well as the mk2. if you look closely at them you'll see the casting is almost identical, apart from the odd shape cutouts for the injectors.

as you say the pf head is almost identical to the DX, and is the same as the later digifant PB head, so will work fine if you had a mk1/2 type carb inlet.  as said the mk1/2 inlet wont fit a mk3 head due to the odd injector holes.

not that any of the above matters anymore since you're going crossflow

with the clutch its a mk2 16v one you need if the gearbox is a 2.0 8v one, the mk2 1.8 8v clutch kit is the same as the mk1 1.8 8v kit. Pluis you'll need a mk1/2 1.8 210mm flywheel to match the 16v kit if the AGG is all original, the late mk3 flywheel wont fit a mk1/2 clutch. you could of course use a late mk3 2.0 clutch kit with the flywheel, but note the late type flywheel is heavier than the early mk3 and mk1/2 ones. To ID what type it is check the locating dowels inside, if it has 2 dowels this means its a mk1/2 or early mk3 flywheel, 1 dowel means late mk3.

All the 1.8 mk1/2 kits are 210mm, your old 1.5 clutch will be 190mm so if you wanted to fit the old 1.5 gearbox and its on the original clutch you'll need a mk1/2 1.8 210mm flywheel to go with the new mk1/2 1.8 8v clutch kit.

To know for sure what gearbox is fitted to the AGG check the code on it, no telling if its been changed as mk3 are harder on boxes than mk1 and mk2. Post the code up here then we can ID, also before you make the final decision to use this gearbox be sure to check if it has the holes for the MK1 gearbox brackets, some dont have them!
020Mount

rubjonny said

the mk2 and mk3 gti heads flow the same or close enough, its a myth that the mk3 heads dont flow as well as the mk2. if you look closely at them you'll see the casting is almost identical, apart from the odd shape cutouts for the injectors.

as you say the pf head is almost identical to the DX, and is the same as the later digifant PB head, so will work fine if you had a mk1/2 type carb inlet.  as said the mk1/2 inlet wont fit a mk3 head due to the odd injector holes.

not that any of the above matters anymore since you're going crossflow with the clutch its a mk2 16v one you need if the gearbox is a 2.0 8v one, the mk2 1.8 8v clutch kit is the same as the mk1 1.8 8v kit. Pluis you'll need a mk1/2 1.8 210mm flywheel to match the 16v kit if the AGG is all original, the late mk3 flywheel wont fit a mk1/2 clutch. you could of course use a late mk3 2.0 clutch kit with the flywheel, but note the late type flywheel is heavier than the early mk3 and mk1/2 ones. To ID what type it is check the locating dowels inside, if it has 2 dowels this means its a mk1/2 or early mk3 flywheel, 1 dowel means late mk3.

All the 1.8 mk1/2 kits are 210mm, your old 1.5 clutch will be 190mm so if you wanted to fit the old 1.5 gearbox and its on the original clutch you'll need a mk1/2 1.8 210mm flywheel to go with the new mk1/2 1.8 8v clutch kit.

To know for sure what gearbox is fitted to the AGG check the code on it, no telling if its been changed as mk3 are harder on boxes than mk1 and mk2. Post the code up here then we can ID, also before you make the final decision to use this gearbox be sure to check if it has the holes for the MK1 gearbox brackets, some dont have them!
020Mount

Hi Rubjohnny.

Thanks for the good info.

Just to clarify - not going crossflow, but staying with counter-flow head I have seen a nice refurbished PB-head, that I would like to buy and which will fit my DCOE-manifold intake-holes. Good to know that this is the route to take. Will the standard lifters and springs from the PF-head be fine or is it recommended to upgrade these with my engine setup?

I will reuse the 1,5 JB 020-gearbox, which is a 4+E in excellent condition and use a 1,8 mk1/2 210mm clutch kit (clutch/flywheel).  Also makes it easy by reusing the existing driveshafts etc. I will not use the AGG-gearbox (I sold that off).

Any advices on which camshaft to use? Is the TT a good choice?

the pf bits are all the same as pb, so unless you're going mental with the cam your old stuff will be fine if in good condition

as for cam its a personal choice really, do you prefer usable low down torque or loads of power up high, you can get cams so wild they're barely drivable on the road and you have to keep the rpms high at all times

once cam is chosen you can then go for manufacturer recommendations on the lifters/springs, but yah if you keep it reasonable all the standard gear is fine. all comes down to what sort of figures do you want and the size of your budget! I kept mine pretty much standard with a GS1H cam (but only because it was very cheap!) this was enough for my needs in my mk2. I even prefered it in standard form over the 1.8 16v I swapped in later, as it had more low down torque. the ABF engine still wins tho

So personally I would say keep it cheap n cheerful, as you got to think if you spend a will get out of a 2.0 16v as standard before you even spend any money

rubjonny said

the pf bits are all the same as pb, so unless you're going mental with the cam your old stuff will be fine if in good condition

as for cam its a personal choice really, do you prefer usable low down torque or loads of power up high, you can get cams so wild they're barely drivable on the road and you have to keep the rpms high at all times

once cam is chosen you can then go for manufacturer recommendations on the lifters/springs, but yah if you keep it reasonable all the standard gear is fine. all comes down to what sort of figures do you want and the size of your budget! I kept mine pretty much standard with a GS1H cam (but only because it was very cheap!) this was enough for my needs in my mk2. I even prefered it in standard form over the 1.8 16v I swapped in later, as it had more low down torque. the ABF engine still wins tho

So personally I would say keep it cheap n cheerful, as you got to think if you spend a will get out of a 2.0 16v as standard before you even spend any money

Good - Then I will look for a decent PB / PF head to fit the AGG-bottom and the new camshaft (with standard springs, but new lifters). I will go for the TT 276. In terms of figures I will be happy with 140 HP or around that mark.

Any advices as to the belts and pulleys for the alternator?

One belt goes from from crank to alternator and climate pump. And one belt goes from crank to waterpump and to power-steering pump.

Can i swap some of the pulleys from my 1,5 JB?
Ie. crank directly to alternator and waterpump.

if you want to delete aircon/climate remove the compressor and swap the waterpump pulley for a mk3 1.8-2.0 non-aircon version, then use the right non-aircon belts matched to the year of the car it came from (2 lengths of alternator belt) to dlete power steering just delete it and its associated parts, the waterpump on the non-aircon setup is run from the alternator belt

you can fit all the older alternator parts if you like, but the mk3 stuff is better

Thanks so far.

I have gone ahead and bought a few new items.
For the head I have found a 1,8 litre G60 PG-Head fitted ex works with 40mm intake valves and 33mm exhaust valves.

It seems that it is possible to fit 41mm intake and 33,5mm exhaust valves in the existing seats - Can anyone confirm?
I want to get the head P&P'ed and in the same time fitted with stronger springs etc.
I will go for the valve kit with 41x33,5mm staines, from Techtonics-tuning.
Any ideas of how high this setup could/should rev to (Redline)?

For the camshaft I was lucky to pick up an almost new Schrick 276 cam, that I Will use with new lifters.

if you're sending the head away for work aim those questions to the guys doing the work

the 2.0 bottom end internals are quite heavy so i believe that will limit just how revvy the car is, but im not a massive expert on 8v tuning as I looked into it, saw how much you had to spend to get near 16v power levels and gave up on that route altogether

Hi…I'm guessing your in the USA?

For a cost effective road going set up the std valves will be fine…a 2ltr with a ported std valve head with a 276 cam and 45's will make 160hp with ease if the head is done right.

Of the heads I've checked, they will take a 40.5mm inlet no problem but a 41mm is very very tight right on the edge of the seat. As for exhaust the std seat won't take anything other than the std 33mm valve comfortably….0.5mm bigger will gain absolutely nothing in power anyway….so if 160hp with strong torque…around 150ibft…is enough for you save yr self the cost of that expensive kit.

Std springs will cope with the lift of a 276…0.450?…and as it will make peak power around 6250rpm you won't have an rpm issue with them. I would recommend checking the fitted length of the std ones and compressed length to ensure no coil binding as production tolerance needs to be checked but they should be fine…I've not had a problem with the above spec.

The manifold port sizing and matching is critical to getting the carbs to work. The manifold ports are too small as cast…ranging from minor to major porting needed depending on the manifold…early castings are terrible!…New ones much better…but all need matching and "porting through" the align the ports properly. Use 60mm trumpets which fit ok…just…but don't use sock filters!…They are absolutely rubbish and kill flow and power.

Make sure the c.r is correct for the cam…around 11:1 is the aim with a 276…or it will feel flat.

Don't block off the block breather…use the o.e plastic breather box and vent to a vented catch tank.

Hope that's a help.

JMRacing said

Hi…I'm guessing your in the USA?

For a cost effective road going set up the std valves will be fine…a 2ltr with a ported std valve head with a 276 cam and 45's will make 160hp with ease if the head is done right.

Of the heads I've checked, they will take a 40.5mm inlet no problem but a 41mm is very very tight right on the edge of the seat. As for exhaust the std seat won't take anything other than the std 33mm valve comfortably….0.5mm bigger will gain absolutely nothing in power anyway….so if 160hp with strong torque…around 150ibft…is enough for you save yr self the cost of that expensive kit.

Std springs will cope with the lift of a 276…0.450?…and as it will make peak power around 6250rpm you won't have an rpm issue with them. I would recommend checking the fitted length of the std ones and compressed length to ensure no coil binding as production tolerance needs to be checked but they should be fine…I've not had a problem with the above spec.

The manifold port sizing and matching is critical to getting the carbs to work. The manifold ports are too small as cast…ranging from minor to major porting needed depending on the manifold…early castings are terrible!…New ones much better…but all need matching and "porting through" the align the ports properly. Use 60mm trumpets which fit ok…just…but don't use sock filters!…They are absolutely rubbish and kill flow and power.

Make sure the c.r is correct for the cam…around 11:1 is the aim with a 276…or it will feel flat.

Don't block off the block breather…use the o.e plastic breather box and vent to a vented catch tank.

Hope that's a help.

Wow! That was a useful post I am from Denmark Just checked your website - love the section with customer cars and the numbers that Tony Barbers 2litre 8v is pushing.

I would be very happy with 150 hp and thrilled if 160 is possible with this setup and standard valves. Will definately stick with the standard valves/springs and then go for a good P&P, as well as inlet manifold port matching.

Schrick Cam is with 11,5 lift, which must be the same as 0.450.

What is best route to get from 10 in cr to 11? Just using a 0,7mm racing metal headgasket?
The original is around 1,65mm thick.
Found a gasket at Bar-Tek-Tuning.

I take it that you offer port jobs for heads via JMR?

Your welcome…

Thanks…yeah Tony's is a bit special, there's a crossflow head version too racing in the UK.

Well my road & trackday mk2 makes 150hp still on the kjet system and plenum but running a 284 cam and std valves. That's pretty quick on the road with strong torque…It would be better again on 45's…so no reason for you to not see around the 160hp mark with your spec and all the detail work done.

Yes that's right. The problem with std springs is age….they are getting old now, but there's enough around to test. From memory they coil bind at around 0.480-0.490 depending on the fitted length.

The way I do them on full builds is machine the raised "D" section off the piston crown then mill the block down so the whole crown is raised by approx 0.025 into the 1.65 (0.065) head gasket to achieve a 0.040 piston to head clearance. I do that to bring both side of the chamber squish into play.

I sometimes reduce the piston bowl size by further decking if it's a budget competition engine running a sub 300 degree or more cam and 12:1+ c.r. If it's a road engine the c.r is corrected just by head skimming…approx 0.008 per cc reduction.

A 0.7mm (approx 0.030) head gasket is too thin as the std piston squish pad protrudes approx 0.020.

I do yes…current waiting list is long tho pre race season!