abf cams into 16v KR engine

[Geo7087 10]

Being new to the corrado and new to the 16v engines as my previous car was a VR6 my car has a kr 1.8 16v engine and is apparantly fitted with ABF cams?

 

What effect would this have and what are the advantages/disadvantages of this modification?

[andycowuk 0]

Its been a while since I last fiddled with a 16v... but I put KR cams into a ABF not the other way around. The abf cam duration is suited to lower range torque rather than high end power, and I believe they dont have as high a lift as the KR ones.

[Geo7087 10]

So in theory thats going to be more torquey and slightly less rev happy im guessing? not sure what id rather have

[davidwort 0]

ABF cams are actually higher lift than KR ones, they were developed for the later heads on the ABF engines though with full EFI so in reality you won't get much of a different result from the two, possibly shift the power band up a little with ABF cams due to the higher lift and duration. KR pair work very well though.

[Geo7087 10]

So all in all would it be worth reverting back to KR?

 

Friend of mine has a KR head also so may be able to port and polish the inlet manifold for me :)

[davidwort 0]

KR cams give a nice torque spread but also a nice strong midrange and top end, the more advanced EFI and extra capacity of the 2L ABF means you can get away with higher lift cams without sacrificing bottom end torque.

There's not a massive difference, but KR cams would be my favourite in a 1.8.

[pumbaa 0]

Interesting reading. I'm running abf cams but i have a 2.0l, its been remapped but i dont remember feeling any loss of bottom end torque before. probably minimal anyway.

 

The abf cams do have a higher lift and duration with the exception of the exhaust cam which has a shorter duration. I've never heard of anyone putting kr cams into an abf engine, surely it would only result in a loss?

 

davidwort - would you still recommend kr cams in a 2.0l?

[davidwort 0]

davidwort - would you still recommend kr cams in a 2.0l?

 

absolutely, 175bhp and 153lb/ft on Stealths rollers, that's nearly 140bhp at the wheels, and that's with 140K miles injectors on it that are not spraying perfectly! It makes a very smooth power delivery and pulls right to the red line strongly, admittedly with a slightly worked KR head.

I've got a pair of ABF cams I'm going to do a direct swap/comparison with soon but I can't see they will do anything more than push the torque curve up the rev range a bit, which will lose some bottom end, maybe not much but possibly enough to slow the in-gear acceleration times a bit, possibly make even more of a difference on the original 2.0 16v cars as they have slightly longer gearing than the gearboxes from the 1.8's.

[boost monkey 0]

lbft not lb/ft :D

[pumbaa 0]

@ davidwort. Here's hoping you're wrong, as i've spent a lot of time, effort and money using abf cams and a re-map! (mainly the re-map) Which will always play on my mind if the KR cams produce better results!

 

Yours is a 2.0l audi 6a block with KR everything else right?

 

@ boostmonkey - spot the engineer! Side question - If you're using cad 2011, does it crash every time you close a drawing? Its seriously getting on my tits! Im actually considering going back to '98 or even '94!

[davidwort 0]

:) lbft, more of a pedant than I am :lol:

 

pumbaa, If you've had a custom remap of the KE-jet for your head and cams, I'm sure you're going to be getting pretty much the best you can from your engine, the cams aren't so different to change the whole character of the engine and the ABF cams probably do mean you can get the best from your flowed head.

The only 16v engines I've seen that push out more than about 170bhp are very high revving, very lumpy cammed ones and IMO that spoils the easy-going nature of the 16v at low revs, last thing I want is a car that has to idle at 1500 revs, is prone to stalling and has to be revved like crazy to get that extra 10-20bhp

:)

Would be really interesting to compare our cars, as apart from the cams and KE-jet they are very similar specs, I went for flowed and polished standard inlet and exhaust manifolds, I'd imagine the 4 branch changes the engine characteristics a little too, in theory it should rob a little torque at the bottom end but gain a bit at high revs.

Has your rev limiter been upped too? 9A KE-jet is only about 6,500 isn't it?

[pumbaa 0]

Yep, the limiter has been raised so it revs cleanly to the red line and the fuelling has been adjusted so it doesn't lean out t the top. I think it was originally limited to 6500 or 6800.

 

I do have a kind of flat spot at very low revs but no more than what was there with the 9a cams. I thought that was the 16v character. (or I need a new / stronger clutch) but I do remember my old mk2 feeling like that.

 

It may be all in my head but I'm sure she pulls away harder sometimes more than others. I may have to investigate.

 

I've been meaning to get power run done for almost a year now but I never seem to get the time. I'll be sure to post up results when I finally do!