Not quite what I expected

Not exactly sure what has got your goat about these filters, as I can testify from personal experience that they didnt rob my (ex MattD) ITB'd valver of 20BHP..The quality of the filters, however, was indeed poor.

Mapped to 193BHP/148lbs/ft on the Track & Road Dyno Dynamics RR by Steve Greenald happily making power to 7700rpm (socks fitted).

If the engine had a further 20BHP in it Steve would have mentioned it & removed them for the mapping being the clever bloke he is.

An XE is a better engine & easier to coax power from, so maybe the filter socks become a limiting factor in high BHP applications, but you wont gain ~20BHP on a mild spec VW by removing them

 

did you test them properly back to back?

SBdev

"Important Notes
Read below before you waste all the BHP you have spent lots of hard earned money on achieving & throw it away on the intake system.

1. Never use Ram pipe sock filters of any type, you will lose between 20 to 60 BHP."

the surface area is restricted to the bellmouth diameter, whereas with a remote or DFV type filter it can breath through the whole thing.

 

I can vouch for the db absorbtion of the SBD airbox, the fibrelass making a difference between a day marginal on noise, and a day untouched, at Goodwood a few years ago.

 

I ran with and without filters on me old jetta way back when....

the losses from socks fitted were less than 10bhp, and on the dyno used at the time, in the realms of measurement scatter

 

It would be better to state you may suffer a performance penalty in % rather than actual measured numbers as we have been discussing ultimate dyno numbers vary.
And you are correct without testing back to back the "loss" if any, may just be speculation on an otherwise STD head and block.
The plot shown by altern8 looks like the torque correct profile for one of these engines in STD but optimised form. I do not know what that Sun dyno is like in measuring 16v engines generally to correlate to what we see on here to what was tested there. From operating experience on a Dyno Dynamics mahcine a typical good ABF engine will peak around 140-150lbft and more torque if K jet is tweaked or mapped properly and up to 160lbft if you really have a log time to develop the cal. On the dyno I am associated with 130ish+ lbft is average for this engine, usually observed on a MK3 16v with emission controls Digifant 3 and lambda 1 requirement to 4500rpm where it then switches to open loop fuel. After this condtion occurs you achieve peak torque which then dips slightly due to protection fuel. On such an application the torque profile is peaking around 4500rpm then dips slightly to around 5K or so where it ramps down, dropping off sharply at 6.3K or so.
On a more optimised example the torque will peak at 5.5K then ramp off to 6500rpm or so then drop off sharply.
In a ITB set up with the stock cams and compression and a good SEM cal, the torque will peak around the same 5.5K ( usually at the same value as a plenum inlet) but will ramp down much slower to around 6.7k or so rpm then drop off but still much slower than the other examples. There may be a time to max torque penalty at sub 2.5K engine speeds because of the ITBs and or lack of a plenum.
altern8 plots shows the latter trend suggesting the itbs are assisting trapping efficiency as expected with a good SEM cal.
So how does this vehicle compare to a previously tested "150bhp/145lbft" on dyno brand A, that is known to be reletively quick when operated on the road or track. If we can answer that objectively then we can start looking into any potential benefits or drawbacks for the given hardware. This is fairly difficult to validate when behind a PC screen and keyboard.

 

My response was to those saying, hmm looks a bit low that, start with the obvious stuff first, then delve into cam timing/calibration etc

 

I agree. Except we do not really know if for that dyno the car is actually reading "low".

 

There is something a little bit more to a 155bhp output than whether it runs filter socks or not though...

For SBD to say 20-60bhp lost is a sweeping statement and very bold.

There was no way my engine had an additional 20BHP in it. Replacing the filter socks for an airbox would not be a priority of mine.

I agree that additional power can likely be found on a higher spec engine when airflow becomes all the more critical (higher rpm/hotter cams etc etc). With the mild spec of this motor though, I think bigger gains will be found elsewhere initially.

It needs mapping properly for starters so each loadsite is optimized for fuel and ignition. With no disrespect to tommies, a DTA expert with the ability to hold the engine at each load site and trim the fuelling and ignition will find power for certain.

 

Also very vague!

 

We do not know that the engine is already at MBT or LBT in certain points of the WOT plot for that calibration. You are also assuming that the measurements posted in this thread the same as the typical results we read about on other machines mentioned on this forum. You may find there may be a delta compared to reality. That is not to say that the general map table settings and config, cannot be polished up to change response of the system.
Not an exclusive job for a DTA "expert".

 

SBD were trying to sell their filters & airboxes obviously. However, they do appear to be pretty thorough in their engine development and vehicle prep, so it's worth following up their statement

 

someone who is familiar with driving the DTA software and has load dyno, afr, knock etc etc would/should be able to optimise whats there tho. you would hope!

 

I am assuming, of course that the rolling road in question is producing "realistic" figures, such that a stock ABF engine on plenum injection would produce ~150BHP, and is not reading very low.

The fact the operator thought it would make more would indicate the power output is indeed somewhat low

I'm sure that SBD have done research and socks can limit airflow and output, however, I don't see the socks being a -20BHP factor when the engine is still running KR cams.

These are very mild for an itb'd setup, especially on the inlet side

 

One airbox

 

one question, why have you changed the abf head for a kr head?

 

You can't do back to back filter tests with ITB's as the ECU needs re-mapping between tests to compensate for the change in air quantity at any given throttle opening, due to a potentially different air restriction. If you don't do the above you could get less power from the better quality filter due to weakening in the mixture.

Back OT: The engine in question looks over throttled to me.

 

I already had a ported 027 head in the shed so I used it on this engine

After I fit the new airbox I'll get it mapped again.

So far I have done about 500 miles and it hasn't missed a beat.

I still need to lower the radiator to get more air in and get some of Bills spacers.

 

Personally mate I wouldn't go back to 'that' roling road. When I took my mk1 there he cooked it and THEN said that he think the head gasket might have gone. He also loaded the rollers soo much I didn't think the wheels would turn hahaha. Honestly, avoid the old bugger, you're only going there cos you're too tight to drive somewhere else