new 10/14/01
On October 13th 2001 about 10 SHOs gathered at Performance Technical Center, Elk Grove Village, IL for a "Dyno Day" Four of the cars were V8 SHOs and I have their permission to reproduce the results here. First, an observation on Performance Technical Center, of all the Dyno Days I have attended they were the most cooperative, knowledgeable and professional. I would recommend them and go back to them anytime.
Because V8 SHOs are not torque monsters I recommended we just punch the throttle off idle and let the cars shift naturally at wide-open-throttle through the gears. We did record the best 1st gear torque information ever recorded for V8SHOs and a lot of other gems. Tim Wright’s car was the only one to test OD on the dyno, just to see the effect of the shift kit on the 3-OD shift.
Everybody got 2 runs and we used the best of the two for comparison. In everyone’s case their best run was their second run.
The Borla cat back system on Anthony Walsh’s 97 showed best off idle torque to 20 mph and good Hp too. If it had only a little less peak HP than Tim Wright that can be accounted for by lack of UDP.
It is difficult to isolate the effects of the Doug Lewis shift kit. Remember Tim’s SHO has slightly undersize tires so to shift at the same speed it has to shift later. Notice the crappy 3rd-OD shift point before HP peaks in 3rd gear the car jumps to OD at 112 mph when the optimal shift point is 130 mph.
All four cars show the quirky converter lockup flip flop at 90-94 mph.
If factory exhaust system was the torque monster that it is reported to be you think it would show up on the 1st gear but it did not. Don had worn tires, maybe we are seeing a traction problem below 30 mph? Maybe if Don did more intake work we might see the result of an improved intake with factory exhaust.
The choice of MPH for the X axis is deceiving in that it is not constant with time. To better understand the effect of the shift kit I compared this dyno result to prior results with the same car. Earlier results indicate shift times of 1.0-1.25 seconds. Now shifts require half that much time. Anderson Ford of Clinton IL did the rebuild and Doug Lewis did the shift kit. Anything wrong with my transmission I attribute to Anderson Ford who kept my car for a month and made a mess out of the rebuild. Anything right with my transmission I attribute to Doug Lewis who repaired the repair and put in a shift kit.
I recorded a net loss of 2 HP (197, down from 199) from prior results but that may because the car shifted 3rd – OD at 112 mph (5700 rpm) well shy of the 6200 rpm HP peak or because I had a tank full of 10% ethanol Huck low test gas. The HP curve is so flat between 110 mph to 120 mph, I don’t know if I would have picked up the 2 HP if I had locked out OD, or it could even be tired spark plugs
It does show the performance penalty for letting the transmission shift into OD on it’s own below 130 mph, you give away 40 HP.
I asked Geoff to just let the PCM "do it's thing" You can see the HP take a tank at a measured 139 mph which indicates maybe indicated 144 mph ~ 139 mph as measured on the chassis dyno.
I had a great time, as always SHO folks are the best!
Well, I just got back from a very fun day in the
Chicago area with several of the SHOcago group.
Tim Wright and I got up there first, about 9:30 am and I was re-united with an
old friend, the dyno I used to own and operate in Peoria. IL. Now it belongs to
Geoff of Performance Technical Center in Elk Grove Village and he treated our
group very well today, doing tests on 10 cars and accommodating Tim Wright’s
requests for print-outs etc. Look for some charts on the V8 cars at least on
V8SHO.com soon. Of the V8 Cars, Tim's was the most powerful, and mine was the
least, but then mine was the only stock (other than K&N panel filter, even
have the Saxicone still intact!) V8 there! Car is doing fine, just need to make
some mods!
Thanks to all the SHOcago people for making it such a fun day, hope to see you
all again soon. OH, and it rained and rained and then POURED most of the day. A
wind gust (maybe a tornado) took part of the roof off a mall in the area shortly
after we left the Chicago Metro.
Don Mallinson
FWIW it was an awful day weather wise while these runs were made. 100%
humidity (steady 3 hr downpour), AP ~29.7. The readings were adjusted up a bit
due to these conditions. There were flash flood warnings out for the area and
traffic on I355 was down to 35 mph! On the way up I was traveling 85-90 (55 mph
speed limit) in a pack along with others and we went right past parked ISP
without even slowing down. What's amazing is that as you get out into the open
rural roads you start to slow down to 75-80.
A Gen1 and a Gen2 SHO pushed past 200 hp and there was a Pontiac SE grand Am
that was there to make us all feel good. He pulled a 175 I think. If you think
our trannys shift bad you should have heard this one. And Don's car got the
carbon blown out as it SHOed its appreciation with a nice black cloud at the
start:)
My '97 SHOed peak HP at ~5750 rpm where it was almost linear to 6200 rpm. This
peak is the mysterious 90mph boost the brain does, mine was 192 HP. After 6200
it began to fall off gradually until cut off at 6650 rpm in 3rd gear.
These rpm # seem to read a bit lower than the tach. I also have a flat 2-3
shift, no peak at all. Comments?
http://www.performancetechcenter.com/index3.htm
Paul Nimz
'97 TR
'93 EG mtx
I think the SE made ~ 167 Ft# TQ, less than 150 HP, it made less HP the the SVT Contour but more Tq, it should 3.8L vs 2.5L?
I have been tell Don he needs to "blow the carbon out" more often. ;-)
The V6 SHOs with mods won 1st, 2nd and maybe 3rd place that day with 198, 199 & 202 HP that day If my memory is OK.
Tim W