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Wed Jun 24, 2009 11:52 pm

Today I started on a mission to test some of the exhuast systems that are available for our buess. While this isn't a totally controlled enviroment style of testing the results may vary but this is what we did so far tonight just swapping headers and running with close to consistent conditions. All this is being done at Geoff Hart Performance engines on his Stuska dnyo.

Engine is a fresh 1904, 8.1 to 1 compression, WEB 119 cam with 1.25 to 1 rockers. Original VW take off heads, 35 intake, 32 exhuast valves. DTM fan shroud (testing the temps using this shroud for desert driving). Ignition is a Chinese 009 copy with a Petronix copy with the timing set at 28 degrees total with a Bosch Blue coil, Bosch plug wires and NGK B8ES plugs.

This engine was built to see how stock and lower end products would work on a budget small stroke and bore engine, designed and built for use in a daily driver bus.

I started with stock rockers and 34 ICT's and was so disapointed I upgraded to the 1.25 rockers and a set of 44 HPMX Empi Weber copies. This gave me over a 10 hp gain and a better test bed .

We started with stock heater boxes, a Thunderbird extractor with an EMPI
Fat Boy muffler. We ran the engine up to 5000 rpm's and got some decent numbers after a few jet changes were pretty pleased with the results.

Next we switched over to the new Vintage Speed stainless header/muffler system for a bus.
This system was very easy and quick to install, finish and workmanship was nice. We gained a little at 2500 rpm's but started to fall off in the mid range and was about the same at 5000 rpm's and it's the mid you want. The throttle response didn't seem as snappy as it did with the heater box/Thunderbird exhuast.
There seemed to be a lot of heat buuilt up where the header pipe bolts to the muffler. We thought that maybe the muffler was to restrictive so decided to remove it. We got no change with or without the muffler install.
We did need to lean the engine out with this system installed with an air jet change.

We ran out of time and hunger pains started to set in so we called it a night. Tomorrow I am going to bolt up an A1 1 1/2 inch Sidewinder with
their Magnaflow muffler to see how it compares to the other 2 systems.

I will post the complete dyno numbers on these three systems tomorrow and then maybe put on a stock bus muffler to see what happens.

1 of the limiting factors though in this testing is the STOCK non ported stock valve heads, but I wanted to see if any of these systems could/will improve performance or hurt it and if it's worth the money to even change.

If I feel ambious after this series of testing I might change the heads out to a set of CB's Los Panchito heads. These are a new CNC mild ported head with 40 X 35 mm valves using Genuine VW castings and are reasonable priced. This would increase the performance of the engine (up to 20hp gain or more) and run the sames series of exhuast systems with the better flowing heads.

I'm posting this now as everything is still fesh in my mind on what we're doing and hope this info will be usefull for some of you out there that have bigger then stock engines. I am only testing systems that are the most common found on buses and I easy use or have considered using, thus no testing on others systems, so far this has been very interesting and informative to me and those helping.

Dyno numbers, pics and maybe a video or 2 will be posted tomorrow evening.

Thu Jun 25, 2009 5:32 am

I would like to see the Monza exhaust that everyone seems to hate trested. I like the four exhaust tips. I know ya'll will hate me for it, but I like that look. And, at least one person on here reported good results with it. I trust your unbiased approach.

Thu Jun 25, 2009 5:41 am

dont forget a stinger with/without baffle. and the single quietpac. once you covered the normal header switch to a merged to see how much more power it makes. of course where the power is made is as important. we gotta keep the power in the low-midrange for our buses. good luck.

Thu Jun 25, 2009 5:51 am

Good work Ronnie. This will be some really useful information for a lot of us.

Thu Jun 25, 2009 6:26 am

Be sure to record all of the environmental data, too: temp, rh (do you have that in AZ?), "Hg, etc.

Thu Jun 25, 2009 8:07 am

Great idea Ronnie. It will be awesome to have some comparisons with the motor in the bus, driving!

This could not have come at a better time, as I am in need to an exhaust replacement.

Thu Jun 25, 2009 8:09 am

Didn't Berg have an article about this? I know there's some similar tests in the How to Hot Rod VW Engines book too.

Thu Jun 25, 2009 8:29 am

66uno wrote: I would like to see the Monza exhaust that everyone seems to hate trested. I like the four exhaust tips. I know ya'll will hate me for it, but I like that look. And, at least one person on here reported good results with it. I trust your unbiased approach.

We actual discussed testing one from a later type 2 on the Vintage Speed pipes as they have the same flange. But I would never use a Monza so teting one isn't going to happen

Thu Jun 25, 2009 8:31 am

kingodirtp3 wrote: dont forget a stinger with/without baffle. and the single quietpac. once you covered the normal header switch to a merged to see how much more power it makes. of course where the power is made is as important. we gotta keep the power in the low-midrange for our buses. good luck.

We also looked and discussed running a merged but then again you would have to modify the rear bumper for clearance so it is out also. Maybe for shits and giggles we could put one on and run it.

Thu Jun 25, 2009 8:35 am

thom wrote: Be sure to record all of the environmental data, too: temp, rh (do you have that in AZ?), "Hg, etc.

We had the weather station on and kept that data, we could do a correction if needed, but as stated this is not high tech exact testing, just header changes. We will run the sidewinder around 1 or 2 m. today as the outside temp will be close to what we had last night and it's monsoony now so we we should have close to the same air as last night. But with the size and configuration of the test engine air is not that big of a factor as long as we're close.. On the hi po engines we do air is critical to consistent testing

Thu Jun 25, 2009 8:44 am

crofty wrote: Didn't Berg have an article about this? I know there's some similar tests in the How to Hot Rod VW Engines book too.

Yes but the A1 Sidewinder and the Vintage speed weren't available when Berg was alive.

I am testing the systems that people are using today, that are readily available and the most common.

The main reason is to see if 'COST' justifies performance gains. If it's for looks it's one thing, but if your trying to gain some performance it's another.

Like why buy 1 1/2 heater boxes and a matching header for $$$$ if you can bolt on a lesser price header and muffler and see the same or better results with stock heater boxes and a header.

As time permits in the future I will test different systems on a higher performance . A good example was the 2027 in my 60 DC. I started with a 1 5/8 sidewinder, ran good on the dyno made decent numbers but seemed weak at the top. I changed it over to a 1 1/2 inch sidewinder and gained 12 hp at the top.

Thu Jun 25, 2009 9:00 am

splitpile wrote: crofty wrote: Didn't Berg have an article about this? I know there's some similar tests in the How to Hot Rod VW Engines book too.

Yes but the A1 Sidewinder and the Vintage speed weren't available when Berg was alive.

I am testing the systems that people are using today, that are readily available and the most common.

I thought I saw those tested too. Maybe a HotVW's article?

Thu Jun 25, 2009 9:02 am

Ronnie what about running some test on the system you designed, get some more backing to have it produced with some solid dyno results

Thu Jun 25, 2009 9:24 am

nice work, good to see this up to date testing being done...

Thu Jun 25, 2009 9:47 am

auslander wrote: Ronnie what about running some test on the system you designed, get some more backing to have it produced with some solid dyno results

I could do that, it's still on it original test engine in my 60 dd panel, but since it will never be made, there's no point. Testing isn't cheap and very time consuming. I was at the dyno shop from 5 p m till 10:30 p m and we only got 2 done. Each change requires jet and timing changes to try to achieve the max output from the engine. Then you have cool down time between pulls.
http://www.youtube.com/watch?v=vGeijNMuJJQ

Thu Jun 25, 2009 10:16 am

I like the look of a stock exhaust, but I definitely feel as though I'd like a little more power driving a camper as my daily. The 1600SP probably isn't the most powerful engine, but I love its reliability. I'll be very curious to see which system comes out on top.

Thu Jun 25, 2009 10:26 am

Not to hijack, but I would like to see someone fabricate a system using the sidewinder header but two mufflers like Krusher did, but have the entire thing exit through the stock cutout and use the guts of a 60-71 damper pipe and tip. So externally where it popped out behind the muffler it appeared stock.

Thu Jun 25, 2009 10:42 am

Major Woody wrote: Not to hijack, but I would like to see someone fabricate a system using the sidewinder header but two mufflers like Krusher did, but have the entire thing exit through the stock cutout and use the guts of a 60-71 damper pipe and tip. So externally where it popped out behind the muffler it appeared stock.

One of the things we discussed last night was developing our own sidewinder style header (they are being cloned in China now, I heard), that would come out in the stock position. One of the leading custom header builders (does Nascar and troghy truck) in the U S is in Kingman AZ and we are going to make a road trip to visit him and discuss the posabilities. I don't know what he can do and a custom made system averages 200 dollars a hole with-out muffler. We will discuss quantity priceing , like lots of 10 at a time if we can come up with a design that fits the needs of bus owners and WORKS!.

Thu Jun 25, 2009 11:27 am

It's like deja vu all over again

http://www.thesamba.com/vw/forum/viewtopic.php?t=126239&highlight=muffler

:roll:

Thu Jun 25, 2009 12:37 pm

Ian wrote: It's like deja vu all over again

http://www.thesamba.com/vw/forum/viewtopic.php?t=126239&highlight=muffler

:roll:

Except we are just testing existing off the shelf systems now and not making anything, just discussing it. I have enough on my plate right now