3b motor to 500bhp posible? without any problems?

[S2central.net]

you are my man for learn about how to upgrade our 3B engines ignition

wich it is the "wrong wide rotor" as you says??

Thw 'wide rotor' is wrong because it can be cause of phenomenon called 'spark hop' - which is where the spark jumps inside dissy from coil the wrong plug - more common when running high boost as the energy required to create spark in the pressurised cylinder is higher than at ambient inside the dissy... This is essentially why Audi went to direct ignition from AAN onwards.

The combination of uprated ignition amplifier (POS) and coil - used with correct 'thin' tipped rotor arm is a good improvement on 3B - I had no idea it was used for ~1000bhp machines though... That is impressive alright.

Oh and 'spark hop' is baaaaaad - because it causes pre-ignition in the NEXT cylinder in teh firing order - and banana shaped conrods can be the ultimate result of that.

[Rocco]

Thw 'wide rotor' is wrong because it can be cause of phenomenon called 'spark hop' - which is where the spark jumps inside dissy from coil the wrong plug - more common when running high boost as the energy required to create spark in the pressurised cylinder is higher than at ambient inside the dissy... This is essentially why Audi went to direct ignition from AAN onwards.

The combination of uprated ignition amplifier (POS) and coil - used with correct 'thin' tipp ed rotor arm is a good improvement on 3B - I had no idea it was used for ~1000bhp machines though... That is impressive alright.

Oh and 'spark hop' is baaaaaad - because it causes pre-ignition in the NEXT cylinder in teh firing order - and banana shaped conrods can be the ultimate result of that.

and whem we are talking about a "wrong" distributor rotor??

whem it is damaged??because me for example ´the last week i´ve changed it because it lost some part of the plastic


this part it is very cheap ,and i,ve installed the new original part from Bosch but if the 7A it is a bit bigger and betther...,aniway it is enough if the part it is new and we have less than 450hp

thanks Paul

[magarv]

this part it is very cheap ,and i,ve installed the new original part from Bosch but if the 7A it is a bit bigger and betther...,aniway it is enough if the part it is new and we have less than 450hp

thanks Paul

No, the one from the 7A is bigger but NOT better, the wide 17mm rotor can make "banana-rods" at less than 300hp if you are unlucky! As Paul writes: the wide ("big") rotor can make the spark jump to the wrong sparkplug. ("spark hop")
The correct rotor should only be 11mm at the tip

[Jon441cc]

Does anyone rate these or had any experiance with them ?

http://www.034motorsport.com/product_info.php?cPath=26&products_id=277

[Keeper of The Kitten]

Has anybody tested the ground-down rotor arm with the longer trailing edge? The spark-hop issue has been discussed a few times but I don't think this potential solution has ever been fully investigated?

http://www.s2forum.com/forum/showthread.php?t=29457

[Rocco]

No, the one from the 7A is bigger but NOT better, the wide 17mm rotor can make "banana-rods" at less than 300hp if you are unlucky! As Paul writes: the wide ("big") rotor can make the spark jump to the wrong sparkplug. ("spark hop")
The correct rotor should only be 11mm at the tip

and then wich it is the correct rotor to buy and install in our distributors??

oem new 3B ones?? early 3B? or laters 3B??

thanks for your help man

[Jon441cc]

Rotor with an 11mm Tip as magarv has said

[Rocco]

Rotor with an 11mm Tip as magarv has said

yes yes..but where it comes from??model ,year,car,part number...

[Jonnybravo]

I've said it once I'll say it again, I do not believe ALL these power figures from accross the ocean.

Over 1000hp and the best it can manage is that time ?

Don't get me wrong that is VERY fast but strange how cars in this country with less power have run faster and on treads as I expect the Audi runs slicks as most drag cars do out there ?

It takes awesome skill and knowledge to build a reliable 600hp engine let alone one thats approaching 1000hp so I am not saying he doesn't know what he is doing, I just think the power figures are a bit optimistic.

Back on topic though, most engines can be reliable at 500hp if you use the right components, some say its ok to cut corners as its worked for them but to be what I would class as reliable you want some deep pockets.

If the Audi Rally Team thought they could build a 550hp engine without using half the bits they did I am sure they would have to of saved some money, strange how years on (and this works with any manufacturer) people seem to think they know something these people didn't even though they had a budget larger than your morgage..,.. and some lol.

Swings and roundabouts, I've not built a 500hp 3b or ABY but from being involved in Vauxhalls I know what to expect and its mega expensive, I'm not a massive fan of cutting corners as I know, as I have seen it that cutting corners will eventually end in it costing you double what you first intended it to.

[S2central.net]

Anyone running the WIDE rotor arm should file it down to ~11mm width by filing off the *leading* portion of the tip - as per the thread that KOTK points at - I had forgotten that one, but didn't someone post up a part number for some alternative rotor arms - from a spurious application like Toyota or something ?

[Jon441cc]

I think you will find that Audi ran high horsepower rally cars on distribitor ignitions

Anyway, can anyone confirm this part number for correct 11mm dizzy rotor arm for the3b.

Part No: 052905225C

[Jonnybravo]

Thats fair enough but no doubt modified units and either way those engines were used on the limit (as this user or others may use theirs) so the entire engine spec should be well sorted not put in a situation where you are asking 15 year old components to do WAY more than they were designed for when new.

I wasn't actually aiming my post directly at distributors which as it turns out what this thread ended up being about so my mistake there.

The title basically says I want a reliable 500hp 3b, I'm with Jamo on his opinion of what should be used really but either way reliability is a big issue and I am sure like any other engines you are usually better off using modern technology over older methods.

It is just my opinion ofcourse, you don't have to agree

[S2central.net]

No doubt Audi sport ran silly bhp with dissy on the 20VT engine alright, but I'll bet they didn't run with a big fat rotor arm and a feeble coil !!!

That part number seems to look good... my family album lists it as 10mm wide but hey...

Same part lists for late WR and MB engines amongst others - including 'ordinary' engines such as ACE and NG - so its not an exotic rotor arm by any stretch. Notably the KW (sport) has a different rotor arm in there but its maybe made of unobtainium nowadays.

[Keeper of The Kitten]

I tend to agree with Jonnyb here, the new technology mostly is the superior way, and I absolutely agree that even if you fit stock components, it is better to do that than expect many of the old parts to take the load.

My own remarks about the rotor arm were more an idle question about whether the wide trailing edge rotor had been investigated.

However, the original post was indeed about making a 3B operate at 500bhp, and my interpretation was that it meant using the core principles of a 3B ...if you strip away the ignition and the associated ECU and harness and replace it with the ABY system, it is more than halfway to being an ABY. That was really why I thought the distributor question was key to the discussion.

I'll be sticking to the 3B principles for Kitty until I win the lottery or hit paydirt in some other way! Then I would be tempted by some form of coil on plug or other distributorless ignition!

[Jon441cc]

10mm rotor arm is what it shows after having a look.

I also agree with Jamo that the standard 3B ignition system cannot support High hp applications reliably, and going with multiple coil packs is the best option But as magarv has shown it is possible to use the older dizzy drive technology and get good reliable power with a few tweeks to the 3b ignition system.