Dragstrip tuning for street-use??

[Anonymous]

On the Big Six sub-forum, on a thread entitled, "Removing EGR," I made some general comments about re-tuning any street-used engine that has been altered from what the factory built and carefully tuned. As happens, I unwisely made one suggestion that goes beyond my own experience and qualifications, so I'll ask you smart guys about it. I made reference to fine-tuning a modified engine by means of a dyno, or of a long, straight, even, lightly-traveled uphill street (what I call a "dyno-hill"), or of a dragstrip. Now, being a cheapskate, I have had little dyno time, and also little dragstrip experience (none of it in doing tuning), and that is what I'm asking about.

I have read enough to know that a dragstrip can be used by a top tuner as a very effective dyno substitute. What I didn't think about when I was spouting off about tuning, and what I want to know, is whether a dragstrip, which is generally going to be fairly level and certainly not a pronounced up-grade, can be used for street-car tuning for anything other than full-throttle blasts. Are there convenient ways to use during-the-week open track time for tuning the intermediate and transition circuits and spark curve for getting max efficiency in a daily-driver across the engines full rpm and load range?

(I wish I had got a lot more involved in drag-racing, because some of the best engine-tuners in all of motorsports got their skills through the quickly-repeated, easily-comparable results produced by a dragstrip on tuning days).

 

[xctasy]

Yes, you can do it!

I'm working on an electronic Hp/torque gauge. Its not too hard, the main issue is logging gradient, and I use the Honda Accord Vigor Honda Electro Gyrocator Overlay method of mapping, which eliminates the need for GPS by drop and dragging your real position over and existing plot, and it takes the headache out of trying to use GPS or ground probing radar or a gimball to define instant vehicle position and attitude.

http://www.jsae.or.jp/autotech/data_e/14-2e.html

Its so easy to do if you run a 78-93 Fox body with VSS sensor, or any 80 on EEC3 or 4 Ford, the OBDI (GM ALDL 1980 ca, 1981 and the 1991to 93 CA GM's), OBD 1.5 (93-96) or OBDII (97 to date) car. You have to be able to form a Velecity/time graph, and relate it back to those distance/time events. If your road load changes due to the sine theta weight factor, the road graidient must be known. I use the NZMS/Tumonz contors, and determine gradient per distance that way.

In the non ALDL, non EEC 81 Mustang, I use 60, 660 and 1320 feet figures on the flat and at grade with my Campbell Scientific data logger, and its very repeatable and allows you to fill out the whole gammit of torque verses speed details to get a real world dyno HP curve. A quarter mile, depending on grade and gearing, generally uses the first two gears on a standard six cylinder car, and if it does a 16 second quarter mile, the revs per second increase is 400 per second, not much different to a dynomometer set load. When you add a 12 % grade like I use on 3 Mile Hill, you then become traction limited, but if its dry, you are able to run full 0 to 60 mph figures under very high road load. The advantage is you can use coastdown loads too, to eliminate the road load issues. Wind and barametric pressure is a problem, but you can correct for it with a wind vaned pitot tube and I use a very accurate air craft baro gauge and have it electronically logged. The distance is measured by a Rallye Brantz Meter. TPS is best run of the GM TPS unit used in the TBI J cars. Its best to use a cruise control to control the data, and use it as a measuring point.

Real world brake specific horsepower comes in when you use the Ecomodder recomended fuel economy gauge,

the ODBII Scangauge

the OBD I and I.5 MPGuino only for TBI/EFI with Saturated Injectors Hi Impedience, and some low impedience injectors from 1988 to 1996

http://www.ford-trucks.com/forums/pictu ... reid=64472
other pre 1991 cars had it stock, like the 87 Supra
the EFI Cadiilac Seville MPG gauge
the carb on-board GM Holden Commodore Computer 1981 to 1985

http://img.photobucket.com/albums/v345/ ... CF0451.jpg

the carb Fox to pre SN95 Tbrid/Ranger MPG gauge

http://2.bp.blogspot.com/-kJhRqV595iU/U ... 00/TB6.jpg

before the Fox car, there was
the pre Fox SpaceKom

http://img.photobucket.com/albums/v413/ ... 1247996252

and then have a set driving path like I do on my TeAnau and Coastal otago circuits. I have 15 Long Term Pavement Performance sites which I set up in 2001, and they have coastdown figures, roughness, grip test and texture figures so I can
do dyno and combination calculations.

 

[Soldmy66]

In addition to the higher priced Scangauge, members of the Ecomodder website also recommend a much lower priced alternative, the Ultragauge. While the former has more bells and whistles, the latter provides essentially the same core functionality at a much lower (than Scangauge) price.

 

[Anonymous]

Dean, that is a lot to digest for a senior citizen who can feel his shrinking allotment of neurons rolling out of his ears and faintly thudding on the floor, and who will be stuck in the simple (not "smart") carburetor age for whatever is left of his life!! But I'll ponder it some more, while the brighter guys (everybody on Hardcore but me) should be delighted.

There's a company here in Seattle, FlowScan, that has been making flow-meters since the Seventies, maybe earlier.

 

[xctasy]

From 9 bucks https://itunes.apple.com/us/app/dynolic ... 74533?mt=8


to $9, 999 http://www.corrsys-datron.com/

hp measurement has never been easier. Find your regular 660 and 1320 feet section of safe road, maybee with a 8 to 12% gradient, and presto! you have a means of measuring Hp and torque improvement. Hp requirement with grade is just sine theta of the basic weighbridge weight at test.

Do change ups at rpms after the stall ratio tips in, at 3000, 3250, 3500, 3750, 4000, 4250,4500,4750,5000,5250,5500,5750,6000 etc, and you've got the details to define the hp curve without needing a dyno. It couldn't be easier

Or my $ 1600 favorite , the Detective John Shaft 'Richard Roundtree' dyno shaft on car dynamometer
http://www.aemelectronics.com/dyno-shaf ... ometer-73/


http://www.jimmy540i.com/gtech2.jpg

see http://www.jimmy540i.com/gtech.htm

see http://www.sub5zero.com/g-techpro-ss-wo ... ate-gauge/