the brick hits the dyno

tencentlife · Post by **tencentlife** » Mon Dec 01, 2008 9:55 pm

I pulled the engine I've been driving for about a year, a 2.2 NA 9.7:1 wbx, to try a new cam in it, something that would make better torque down low for a truck motor. New cam is fun, CB 2280, "The Cheater". It's been a popular Type1-style cam for buses. I'm running the hydros on it, too, and they work perfectly. I scoped it out first and the way it met the lifters looked fine, so I stuck it in. I have a few thou on it already. Wear patterns look pretty normal so far.

Got it on the dyno last week, with the 2280, 1.1 rockers, and my 4-2-1 exhaust, this one but without a cat and now it's ceramic coated:

At the rear wheels, 94hp @ 4550, 130ft.lb. @3250.

Torque is above 120 from about 2375 to 4000.

A stock 2.1 puts down about 68-74whp and 88-93ft.lb, depending on who you ask. This looks like it has torque that good from 2k to redline.

The WOT open-loop didn't even kick in, my vac switch is adjusted a little too low for the hot engine, so that was pretty much at lambda or just below 14 at the richest. 1.1 rockers, too; the upper power band on this engine opens up even more with 1.25's (not on dyno, just driving), but the mid-range torque seems flatter with 1.1's.

Fun.

MinamiKotaro · Post by **MinamiKotaro** » Mon Dec 01, 2008 11:25 pm

That's some nice torque, especially for a Bus.

fastback · Post by **fastback** » Tue Dec 02, 2008 1:59 am

nice!
stock intake an EFI ??
or other mod's?

tencentlife · Post by **tencentlife** » Tue Dec 02, 2008 8:28 am

Running stock intake but with runner ends matched to the head ports (they are a very poor match from the factory).

My custom TB (same throat size as stock, though, 50mm). See here:

http://www.thesamba.com/vw/forum/viewto ... ottle+body

Digifant, stock except for my vacuum switch that replaces the OEM late mechanical TB switch setup. I've been playing around with the setting on that for the WOT/high-load open-loop signal, because it drifts downward with higher temps. I had it set a little too low so I suspect it didn't close under load and that's why it was basically lambda thru both pulls. I have an indicator on the dash to monitor the switch action, but forgot to tell the dyno operator to watch that it lit under load; I suspect it didn't.

A friend is working up an all-electronic version of the vacuum switch, that will temp-compensate.

tencentlife · Post by **tencentlife** » Tue Dec 02, 2008 8:44 am

I'm reticent to directly compare my engines to what else is available, because I don't want to be seen as putting down the excellent work of others that I also admire, but the whole reason people ask for dyno numbers is comparison, so here's a couple whp charts from 2WD Vanagons to compare to:

http://www.bostig.com/products/bostig-20/why-bostig (look under "Benefits", then "Wide Torque Band")

The Bostig Zetec torque band extends a little longer so it makes some more hp past the peak for the wbx, but never actually lays down as much torque at the wheels as this thing has from 2250 to 4500.

GoWesty has some dyno numbers up for their 2.5 wbx. They present their chassis-dyno figures as flywheel numbers by uprating for driveline losses at a head-scratching 32%! I think it's more like low 20's. Maybe they need to adjust those brakes. Anyway, if you derate their published flywheel numbers by their 32%, this engine is putting down almost identical hp and torque at the wheels:

http://www.gowesty.com/library_article.php?id=111

http://www.gowesty.com/view_large_pictu ... no_3_4.jpg

Of course the exhaust is a big part of the picture. It's designed to peak torque at 3200, so I guess I did something right. The difference this system makes compared to the S&S I used to run is huge.

Anyway, people want to compare, so there's some comparisons. Take them for what they're worth; it might not be much.

I couldn't find a rear-wheel dyno of a EJ22 SubyVanagon. If anyone has seen one I'd like to have the link.

regis101 · Post by **regis101** » Tue Dec 02, 2008 6:15 pm

My air cooled bus cruises best at 3200. Something like 63 mph.

Impressive numbers especially that your engine will live for a long time.

I admire that the boxer makes more torque than hp. Good package.

Need to get you a cam doctor to profile the available cams.

What are the specs of CB's Cheater?

Maybe 225@050 with .450 lift

I like Elgins writings about shorter lift with longer duration. Isky likes symmetrical. Camshaft talk is endless. sigh

tencentlife · Post by **tencentlife** » Tue Dec 02, 2008 6:59 pm

Yeah it's a whole other language.

The 2280 is adv.274, 222@50, .359 on the cam. 1.1's put valve lift at .394; 1.25's make .448. I had the 1.25's on and will put them back, but I have to shim the valves up a bit. With the short duration and quick lift the intakes would float at 5000rpm.

I decided to go ahead and dyno it this way because with the 1.1's on it the lift is more like the 2252 with 1.25's that I put in my engines for sale, so this was as close as I was likely to get for awhile to the engines I sell at the moment. My van is always testing something new so I never have what I'm actually selling in it to test. Having driven the 2252 with 1.25's for a year before, but in that engine I built a couple years ago with the GW piston set and 9:1, I'd have to say the cam characteristics are pretty similar with these combos, hp doesn't build so big but the torque band is very nice for takeoff and long and flat for cruising, but I'd say it comes on lower and stronger than the 2252 does.

Once I see how the lifters and cam wear for awhile I'd like to start using the Cheater, especially for NA Syncro engines.

regis101 · Post by **regis101** » Tue Dec 02, 2008 7:05 pm

Using the factory FI and ignition puts limits on the camshaft choice. Plus you're looking for torque down low to pull the heavy Vannies. I think you did a damn good job. You found Hp and Tq from meticulous blueprinting.

Back in the day, when we were trying to reinvent the internal combustion engine, Headers by Ed was used to help us with diameter and length. Give them your info and they'd reply back with primary length and diameters. Step headers are a step up from that. Blah, blah.

And as if that don't beat all get out, you can always put the 1.25's on the exhaust side for some more magic.

Then again your header probably flows well enough that you don't need to worry about extra evacuation of the spent gasses.

It's a disease. It gets in your blood.

Post by **Piledriver** » Tue Dec 02, 2008 9:53 pm

Nice.

As to an adjustable vac switch...

SMC ZSE-30, -30inHG-15 PSI, programmable, various output options, and cheap on EBAy. Bullet proof and run fine on 10-30V. 200hz sample rate, stick it on the dash for a gauge, it's ~25mm cube with a fitting.

tencentlife · Post by **tencentlife** » Tue Dec 02, 2008 10:29 pm

Thanks, guys.

I'll look into that switch, Greg, but my buddy has already worked up a solid-state circuit based on an electronic vacuum sensor. I have the prototype in hand already and will actually get to test it a bit tomorrow. It's an IC-based circuit so he can modify by just writing code for it. Shouldn't cost much more than the hardware I'm using already, which I've sold several of and people like them. Only problem with the mechanical one is the setpoint drift downward with heat, so it has to be overcompensated. If we like the electronic one better we'll upgrade everybody with the new version for shipping, in all likelihood.

Post by **Piledriver** » Tue Dec 02, 2008 11:04 pm

tencentlife wrote:Thanks, guys.

I'll look into that switch, Greg, but my buddy has already worked up a solid-state circuit based on an electronic vacuum sensor. I have the prototype in hand already and will actually get to test it a bit tomorrow. It's an IC-based circuit so he can modify by just writing code for it. Shouldn't cost much more than the hardware I'm using already, which I've sold several of and people like them. Only problem with the mechanical one is the setpoint drift downward with heat, so it has to be overcompensated. If we like the electronic one better we'll upgrade everybody with the new version for shipping, in all likelihood.

The SMC ZSE-30 is an electronic unit--- digital readout, industrial temp range, sealed, button programmable unit, and usually costs ~$30-$50 used, maybe ~$100 new.
It is relatively bullet and idiot proof. It was virtually made for this app. No homebrew required. Digi-Key even sells them.

http://stevenengineering.com/Tech_Suppo ... SZSE30.pdf

There are several version, NPN or PNP output (use either to control a relay, or use directly <~50mA) and even an analog out version.

I have been using these and similar SMC switches for years... You'll never consider a mechanical again.

If your buddies unit has multiple relay outs 2 or more w/programmable setpoints and adjustable hysteresis, I'd be interested.

The SMC one that has that is pricey, and I only have one that can do separate vacuum and boost setpoints...

51MAN · Post by **51MAN** » Thu Dec 04, 2008 12:33 am

Nice one Chris.. You ARE the man....

real numbers... just the kind of engine I want to do for my Syncro... wonder how it wold perform on my "small" carb or with a 32/36 on it.. (yeah I know... WTH

) I do have a couple of sets of DJ injection though, so might look at fitting that...

Zorst... I want one... just like my design, the other side to get away from the clutter on the left... looks like as good if not better ground clearance too...

tencentlife · Post by **tencentlife** » Thu Dec 04, 2008 7:29 am

Thanks, Si.

The aim was to make it a good truck engine instead of going for max hp. I had been using that CB 2254 cam, the excessive overlap was what prompted me to design the exhausts I did, and that combo would have been great in a lightweight vehicle. But in the end I was up against the Digifant rev limit anyway, since I'm designing for longblocks to be stuffed into Vanagons. I have to find the combos that have torque and good flexibility.

The 2252 already works well in my builds, and this 2280 will be another useful stick in my quiver once I see how the wear looks after a lot more miles with the small-face lifters running on it. But it really is a great torquey cam, really doesn't need ratios because the lift on the cam is already pretty high. With 1.25's the valve springs need to be shimmed up a little but the lift that way is pretty huge for a street engine. I'm thinking the best combo there might be what regis was talking about, just putting 1.25's on the exhaust side. When I did that mix on the 2254 the off-idle torque was amazing. So I'll definitely be trying that, too.

I have to start looking in earnest for someone to manufacture at least the tubing sections for the 4-2-1 exhaust, and I would do the final fitting in my shop, or else someone to build it complete provided I'm assured they can get the fit right every time. No one wants a bad fitting exhaust, we've all been there. But you're not the only person asking after that; the potential market looks pretty big.

Got a chance to road-test the new electronic vac switch circuit; it worked just as designed, and after a two-hour highway run and some in -town running around to get it good and warm, the set-point hadn't drifted at all, which was what we are after. Now we'll add some extra features: first off will be a reed switch or two for auxiliary circuit, lfor instance to ground out a dash LED. That way you can know when it's idling correctly and see when you are open-loop under load. It could be used as an economy driving feature and just to see that things are working as they should.

51MAN · Post by **51MAN** » Thu Dec 04, 2008 12:51 pm

Yep, just what I want to do... solid grunt and usable power with reliability... I want to drive it 100k before work... ok, maybe 60k would be good...

I reckon oils have a big factor on the cam and lifter wear now... going on a lot of work Charles (LN Eng) has done... High zinc etc oils are needed.. I am actually trying to get an independant to make me a batch of high zinc 10w50 with high thermal stability... this could be used in air and water cooleds...
A bit ambitious really..... maybe I should just use that "green stuff"

Funily I have got the sole rights to sell it in France.... but the importer asks me for more money than I can buy it off the shelf from a UK co that brings it in themselves.... stupid........

tencentlife · Post by **tencentlife** » Thu Dec 04, 2008 3:33 pm

"Green stuff"? You mean the Brad Penn oil?

I'm up on the ZDDP issue, and always careful to use oils that have enough of the stuff. I'm running the SL-rated Rotella 5w40 synth. I bought up all I could from Walmart because it has already gone to SM/CJ-4. I have a couple years' worth!

The reason I'm monitoring wear with the 2280 cam isn't about the oil, though. The cam is a Type1 so it's made for mushroom lifters, but I'm of course running the Type4 small-face hydro lifters on it, so I want to be absolutely sure that they wear well together with no irregularities so I know the combo is fit to put in my production engines. I have to warrant the things, but even so this isn't something that's likely to be trouble in the first year or two. I just want to be certain it won't shorten the engine life so my customers can expect good long mileage from their rebuilds with no lurking time-bombs to cause problems later. I hope it pans out, because it's a terrific grind for a bus.