Porting & Polishing Results

[600Eric]

Although my intention was just to have the heads freshened up to be on par with the overall restoration Matt at Leistung along with 5thscaleracer could not help themselves and had the guy that works on their Cosworth 16V heads spend some additional bench time with them. I'm not sure what this will translate to in terms of a power gain but I guess it is proof there is some room for improvement with the M119 heads. Anyways looks like CFM was increased roughly 15% at top lift. I would love to hear some opinions from the heavyweights on the board (good or bad). Just butt dyno gains or real numbers???




Before.JPGAfter.JPGGraph.JPGHeads.JPG

[gerryvz]

Very cool !! I don't think you're going to know anything until you do some dyno and/or drag race testing. Your butt dyno should be off the scale, though.

I think a mod like this would go nicely with some optimized cams......and one of those Scale Racer exhausts.

[600Eric]

Very cool !! I don't think you're going to know anything until you do some dyno and/or drag race testing. Your butt dyno should be off the scale, though.

I think a mod like this would go nicely with some optimized cams......and one of those Scale Racer exhausts.

Yeah fortunately I already have a Scale Racer exhaust. As far as cams I'm sure you are right but.... (especially since we are talking about 4!). I seriously need to get this car put back together.

[Christian_K]

HEy Eric great. Im about to do this to one of my spare sets of heads in the next month (that was my plan).
Can you ask what the did exactly? Porting to the intake manifold<->Head Ports and polishing Ok, but did they also change the valve-seat geometry?

I will get my cams regrind at Dbilas into the Hagmann Profile, i will try this just to see if and what is possible. If that kills the engine - fine i have another two spares with very low miles sitting in my garage ^^

[gsxr]

Very cool! Don't expect a big gain, but there might be some improvement. Remember that the stock M119 cams are only about 9mm lift max, which is around 0.375". Looks like there is a decent airflow improvement even around 9mm. Bummer you didn't get a "before" dyno graph, but an "after" wouldn't hurt!

[samiam44]

Guess Dave already pointed out you need bigger cams to take advantage of the lift increases. 0.5inch ~12.5 mm. Did you port match the intake and do any polishing there?

Nice to see the head doesn't level out between 10-11 mm which gives you lots of potential.

Combustion chambers are unpolished. Were you going to do an coatings on the valves?

Michael

[gsxr]

FWIW... the RENNtech and AMG cams for 6L are only 10-11mm max lift, depending on the particular profile/cam. I'm not convinced there is much to be gained going beyond that amount of lift.

[gerryvz]

I think some dyno pulls after everything is back together would be hella cool. We basically know what a stock E5er can do, from multiple people doing dyno runs. So this mod'd motor should be interesting.

Personally, with stock cams I'd expect perhaps +10-12 HP (maybe 15 max with exhaust), probably mostly at the top end rather than down low.

That's a pure guesstimate though. I also wouldn't be surprised to see as little as 0-2 HP just because everything that we've seen on these M119 engines has pretty much shown that MB did their homework up front, and there's just so darned little low-hanging fruit HP to get with these things....

[5thscaleracer]

Can you ask what the did exactly? Porting to the intake manifold<->Head Ports and polishing Ok, but did they also change the valve-seat geometry?

I will get my cams regrind at Dbilas into the Hagmann Profile, i will try this just to see if and what is possible. If that kills the engine - fine i have another two spares with very low miles sitting in my garage ^^

Changes:
Valve seat for intake is 5 angle with a 45* valve seat (stock)
Exhaust gets a radius cut with 45* seat.

Intake and exhaust ports were reshape to direct air down into the chamber.

Areas behind the guides were enlarged and cleaned up to optimize flow.

New guides with a different profile was used and custom Viton valve seals.

Intake manifold/plenum/throttle body were cleaned up slightly nothing to brag about as the factory units have good air velocity going in. The biggest benefits is porting the head.

Stock valves were recycled but there is improvement with new valves and different tulip profiles. To keep costs down Eric opted to use the stock valves. "If it ain't broke why change it"

I don't advise doing re-grinds on cams.. While you can get some power from re grinds typically they don't last. Hope you have an extra set of cams for when the Re-grinds go flat.

Guess Dave already pointed out you need bigger cams to take advantage of the lift increases. 0.5inch ~12.5 mm. Did you port match the intake and do any polishing there?

Nice to see the head doesn't level out between 10-11 mm which gives you lots of potential.

Combustion chambers are unpolished. Were you going to do an coatings on the valves?

Michael

Intake plenum/manifold were flow tested and proved to be non restrictive. The stock parts have great air velocity by enlarging them all you are doing is increasing air volume but reducing speed.

It's all about moving high volume of air at a short amount of time.

They were cleaned up and matched to the heads.

Combustion chambers are left stock because after CC testing they were with in 3% which is good. Polishing will lower compression slightly and since the bottom end is not being bumped up there was no need.

Cost goes up but no realistic gains...

Stock valves were not coated again no need it's better to upgrade the valves.

FWIW... the RENNtech and AMG cams for 6L are only 10-11mm max lift, depending on the particular profile/cam. I'm not convinced there is much to be gained going beyond that amount of lift.

Realistically this head would be great with a 10-11mm lift camshaft.

Exhaust ports will be flow tested soon. Still playing around with port angles and bowl shape to maximize cfm.

Exhaust Manifolds are being port matched to head.

[samiam44]

Comments-

Dave I dissagree completely with your statements. Renntech/Brabus/AMG *all* had to meet emissions. 10mm seems to be the limit with factory springs and 11mm is probably with new springs only. All these tuners had to meet *emissions*. I don't give care about emissions.

Greater lift requires greater ramps which may impact emissions. Our OE MAF's are sensitive to overlap.

"Intake and exhaust ports were reshape to direct air down into the chamber." Many times ppl add material to change the short-side radius (SSR) which is a common porting technique. You can induce more tumble and/or swirl , generate more power with lower CFM.

"ntake plenum/manifold were flow tested and proved to be non restrictive. The stock parts have great air velocity by enlarging them all you are doing is increasing air volume but reducing speed. "

Absolutely!! You can port those heads to push 500 cfm and then it would generate power till 10,000 rpm. What good is it? I think everyone's will be excited to see how it dyno's.

Thanks for the info on the valve guides being changed. I kinda thought that would need to be done looking at my heads. I'm 2 steps behind you. My heads are going to the porter in June.
Michael

[gsxr]

AMG definitely had to meet emissions standards. RENNtech, I'm not sure... I have a feeling that as long as their cars weren't failing smog tests (remember, this was mid-1990's) they could do whatever they wanted with cam profiles. They couldn't remove catalysts or delete EGR, but if the computers weren't throwing codes, it was probably fair game. Now if you dink with overlap & whatnot enough to make the LH freak out, and have to switch to full standalone ECU... you're getting into a totally separate set of issues. ROI starts to go downhill fast at that point.

Again, I still find it odd that there were no high-lift (12mm+) cams offered via aftermarket sources for the M119 in the 1990's or early 2000's. If there were significant gains to be had with a bunch of lift, *someone* would have cashed in on that train a long time ago hawking cam+spring kits. Not saying there isn't improvement to be had, but I'd recommend conservative estimates in the power gain department.

[samiam44]

Are those Graph's Eric- the Intake or Exhaust flow?

Dave, sniff testing has been here in Texas for a long time- not a new thing. I'm sure to sell the configuration in Texas and California major cities- Renntech had to pass the sniff test.

There was no cash to be made by offering bigger cam packages. That's why it was never done. Out of the 1991-1995 SL and E500E's. How many 11 mm cam motors can you count from Renntech?? All the cars I've seen except for a few W210's and the 6-spd car were stage I engines. So maybe 5-10%? Maybe 1 or 2 customers were willing to spend more ?


Michael

[gsxr]

Sounded like Eric's graphs are intake, and he's working on exhaust next.

Very hard to get data on exactly what RENNtech built, and how many of each. I have a feeling their stage 1/2/3/etc was a very fluid concept. I'm also reasonably certain that they switched to using the same 11mm cams on most all M119 6L builds somewhere in the mid/late 90's, although I can't prove this. Their 1998 brochure lists stage 1 (displacement increase only), stage 2 (adds cams), and stage 3 (adds headers, porting, polishing)... however, the 2004 and 2006 brochures do not mention stages at all.

For the record, my W210 would appear to be a "Stage 2" engine, since it has RENNtech cams. I've never actually seen or heard of a 6L motor with 5L cams but their literature implies it's possible.

[5thscaleracer]

Blue = Stock intake
Red = Ported Intake
Yellow/Green = Stock Exhaust
Purple = Ported Exhaust with different valve seat cut

There was not much to gain from the exhaust side, the split port design for exhaust was very efficient.
Restriction was the Intake ports

[whipplem104]

those are some really good flow gains in the intake side at the .350 lift area. You should put this car on a dyno and another 500e the same day to see if there is really anything there. Or is the rest of the setup the restriction rather than the heads. Even though I have been told that I could get some gains out of porting on my m104 I am hesitant to do so after spending so much money on other things for more obvious flow increases, not to see significant gains.

[600Eric]

All done and I cant get those exhaust manifolds out now fast enough to be ceramic coated:

IMG_8158.JPG

[ubodepaode]

Nice to see work like this done proper and backed up by some data. You will most definitely notice increase in throttle response, which in most cases means more than maybe some 20-30hp gain that you may get here. Cams would be sweet to add.

[samiam44]

I thought I'd add a quote from Vizzard:

So how do you decide whether a port is too big or too small?

DV:- Well you have to understand that as a head porter you could be approaching this situation from two different vantage points. First the head porter may be called upon to produce a design for a spec of engine where certain aspects are already decided on. Let’s say we are going to do a hot street head design where the valve lift is limited by the need for long term reliability. Here the port should not be so big that it continues to deliver an increase in flow significantly past the point of maximum valve lift. If it does than you have just designed a port for a valve train which the engine is not using.
In the second situation the head porter could be called upon to port a head for the maximum power output possible. Here the head is made to flow, consistent with having good port velocity, as much as possible. When that’s done the engine builder then has to come up with the appropriate parts that compliment that cylinder heads characteristics. This is especially important in the cam department.
In the second instance it is really important to keep an eye on the flow increases made versus the port volume increases. When flow only goes up marginally for a given volume of material taken out then the port is probably already too big. However making that statement is close to oversimplifying the situation. At the end of the day it is vital that the port be velocity mapped to establish where the port is hyper active and where it is lazy. Again though this is simplified we can say that the lazy areas need to be filled in and the active areas need to be enlarged.
At the end of the day there is a certain port area that best suits a valve diameter and that this port area is dependent on the down draft angle of the port and just how good the porter is at getting air to go around a corner that normally, it has no desire to do.

So you can optimize a head for a cam and intake or you can increase an flow and find a cam and intake to match.

I don't see 18.9 cfm increase @ 0.35 inch lift = 20-30 hp.


Michael

[Christian_K]

Yesterday i did just read Vizards opinion regarding 4-valve ports in the book "How to Port and test flow cylinder heads". He said that he found the majority of 4 valve intake ports are already way to big which results in low port velocity, so his first step is usually to make them smaller.

[samiam44]

Yep,

Ppl think airflow and don't think mass flow. Air is heavy and it takes energy to go around things. Look at AMG. The LH cars use the 38 mm intake and when MB went to 35 mm intake valves with Motronic- did AMG use the 38mm intakes? Nope- they used 37mm. Could be that 37mm fit the original seats as the parts book doesn't call out a unique valve seat(my hunch). But they got the # with a smaller valve and port.
I've spent some time looking at Guy Croft's work. Most of those 4V heads, they build up the SSR and get more flow.




Michael

[5thscaleracer]

Mass flow?

How is that measured?

Weight vs time?

Volume vs time?


Air flow is usually used to describe the path taken like checking to see aerodynamics.

Air flow does not quantify an amount of air.

But I don't understand what you mean by "MassFlow"

Btw
Valve size is irrelevant it's all in the tulip and seat cut. Those two factors will produce results vs simply increasing valve size.

In reality stock valve size is ideal you never go bigger than stock unless you are altering CR, crank angles, piston or rod speed, cams etc.

The LH valves had a higher tulip profile and no back cut

The motronic had a lower tulip profile so the valve head got smaller.

So you can't really compare the two based on head size alone. A lot of things were changed for optimal fuel atomization.

[samiam44]

Massflow.. I'm saying there is no consideration for the weight of air.

Think of it like starting a siphon, the weight of the liquid pulls it down. Never seen a high-output manifold which was underslug. They are all high-mounted. Look up hp change versus air temp on a NA engine =0)

"In reality stock valve size is ideal you never go bigger than stock unless you are altering CR, crank angles, piston or rod speed, cams etc." Yep and that is were the 6.0 liter crowd is at.
My work on this remains centered on the 6 liter crowd. I believe they are the only ones which will pony up $$ for a workable mode.


Michael

[5thscaleracer]

Ok

Weight of air is air density.

Flow benches are corrected for this based on temperature and pressure.

So the flow numbers take air density (mass) into consideration.


Calculations are corrected to 28" of h2o

[whipplem104]

I would think that the air flow on a flow bench would account for air mass since it is measured at a specific gravity in mercury. So if you knew the air temp and pressure and humidity you would know the air mass flow. This of course does not account for velocity in the engine itself and a ton of other factors in a running engine. I still think that the air flow issues in these engines is the mostly the exhaust and intake manifolds and well the hole package. It is optimized for low end torque and one thing no matter what it is is not going to change that in any significant way. And mostly it will need to be tuned to any changes to take real advantage of them.
And I would love to be proved wrong so do not take this as a definitive answer of absolute knowledge.

[samiam44]

Fluid statics from physics 101.

Pressure=rho g h.

Manifold design creates pressure (dynamic.. mass) which works against the engine. Compact. Yes. Good for max power no.
Whipple 104. Absolutely right. Tuning is key with any fi engine mods to extract power.

M

[BigWillieStyle]

Just so we keep all the data available in the same place. See attached from the details on another thread regarding 119 flow bench #s.

I put the numbers in a brief summary. The variation between the two results is obviously "material" but at least it is a start.

[BigWillieStyle]

Air Flow CFM @ inH2O Conversion Table
Flow Conversion Table.jpg

http://www.dtec.net.au/Tech%20Articl...on%20Table.xls