Miata Mailing List: March 1997, Message #67
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   From: (none)

Subject: Dyno Results

   Date: (none)



The following are the results from todays Mass Miata/APEX Automotive

Engineering dyno runs on the HMS Motorsport Dynojet in Marblehead Mass.





First, all of the cars in both todays runs and in the runs I posted in late

January were setup by Lester Seal of APEX.



All of the results are corrected by the Dynojet for consistent temperature

and pressure. In all cases the acutal results "raw data" were higher! All

numbers are rear wheel numbers. Figure a 25 hp increase for crank numbers.





94 Sebring, JR headers, Borla exhaust, ported and polished heads



        130.4 hp       126 ft/lb torque



92 BEGI Autorotor, 9 psi, JR headers, JR exhaust



       164.4 hp        155.7 ft/lb torque @ 12 deg. timing

       170.4 hp        156.3 ft/lb torque @ 14 deg. timing

       175.1 hp        159.9 ft/lb torque @ 16 deg. timing



94 BEGI Aerodyne, JR exhaust



      No results, rising rate fuel pressure regulator wasn't supplying enough

boost!!!

      We'll run this car again next month.



90 CAI, JR Headers, Borla ( see January posting)



90 CAI, JR Headers, Borla, ported and polished heads (see January posting)



The actual results on the Autorotor at 16 deg. timing advance were 181.3 hp

at the rear wheels which correlate to about 205-207 at the flywheel!





BAD NEWS!!!!!



We made 20 runs with the Autorotor today with adjustable cam sprockets on

both the exhaust and intake cams. Only one of the combinations, 2 deg advance

on the exhaust, stock intake timing, resulted in a gain. Unfortunately this

gain was only 2 ft/lb of torque in the midrange, with a slight loss of hp at

high rpms.



In this case adjustable cam pullys reduced the power available across the

board!!!

Oh well, nothing ventured, nothing gained!



The real disapointment was the Sebring. Once again it seems that the claims

made are substantially below what the actural results are. We even tried new

plugs and retightening the belt to no avail. What is especially strange is

that the Sebring shows a distinct loss of boost at higher rpms. It maxed out

at 6 psi in the midrange under load at full throtle and backed off to around

3 psi above 5800 rpm. These results were consistent across 6 runs.



Next month we will be running 11-12 psi on the Autorotor with 310 cfm

injectors and a new ECU thereby eliminating the MAS.........and a few other

tricks a-la-Lester!



Gibb

Mass Miata

92 Autorotor with Lester tricks. :)





ps. If you have a BEGI kit on your car and want to get the maximum power out

of it you really need to find a Dynojet to tune it. We found 7 hp by getting

the fuel pressure correct (base and rate of change) and today found 10 more

hp from timing advance and a couple of other tricks.



Unpaid advertisement......if you live in New England see Les at APEX and find

a dyno!!