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1ST DYNO TUNE NUMBERS

CALLAWAY1988

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1988 CALLAWAY
Ok guys. Need some info.. I am trying to attach a copy of my dyno graph. I am not the most proficient user of this computer so you may have to help.
I have a jpg file from an email but cannot figure how to put it here.
 

CALLAWAY1988

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1988 CALLAWAY
Well, I finally got the file to the correct size, but, it is too difficult to see. So I will tell you what I have and what I need. First, after doing some dyno tune work, we were able to get 388rwhp and 482rwtq out of the car. Our problem we have run into is that the air fuel ratio had been as high as 15.2 at 3900 rpms. After tuning, it was down to 12.9 at the same place. I am running a 58 mm throttle body with large tube ported plenum and large tube runners. I installed at the time of engine rebuild, a set of gm injectors part number 10108481 which I believe is a 28lb injector. What is the largest injector you guys may be running and did it require a different fuel pump or supply pump? Where might I find some info on the operation and performance of the boost injectors? Not sure if they are pulling their weight. We believe if we can get some more fuel to the car, it would be even more fun. Thanks for your help in advance... billy
 
S

SurfnSun

Guest
might want to get all you injectors cleaned and flow tested. Add and adjustable fuel pressure regulator.

Does you car have the big Wonderbar?
 

*89x2*

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Where might I find some info on the operation and performance of the boost injectors? Not sure if they are pulling their weight.

Billy, look under the "MAINTENANCE & REPAIR" tab at www.callawayownersgroup.com for general info on the operating systems of your Twin Turbo Callaway.

An excerpt from the data:

The next thing to look at is the "Microfueler" system. This system consists of the additional injectors mounted on the "rams horn" (the casting in front of the throttle body), a black box, a wiring harness, and a fuel hose connection from the fuel rail at the intake manifold. This system is there to provide additional fuel to the engine under boost conditions only. The injectors are driven by the black box mounted on top of the kick panel over the drivers knees. This box senses engine RPM and manifold pressure, and drives the injectors accordingly. With the exception of relying on the fuel pump for pressure and the tach connection on the distributor for engine rpm it is 100% independent of the car's engine control system. Failure of this system will cause a lean condition in boost that will at a minimum make the car feel down on power, and at worst will cause engine misses and/or detonation. Another possible failure with this system can cause it's two injectors to be held open constantly when the ignition key is in the run position. This will flood the engine and cause a no start condition. If disconnecting the electrical connectors at the injectors enables the car to be started than there is a problem with this system.
 
S

SurfnSun

Guest
I have most of them stored on my harddrive or in my head :D

Right off hand I know.

Mine, 90Callaway's, EricVonHa's, boostedmaxpsi, Ultra Slow's, 632c2's, and one or two more.

I have only seen dyno sheets for a few though.
 

CALLAWAY1988

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1988 CALLAWAY
Billy,

What kind of exhaust are you running? Cats?


NO CATS. APPEARS TO BE FROM TURBOS TO ONE PIPE NO CATS, NO EXHAUST EVEN... GRANDFATHERED IN FOR EMISSIONS.. NOT TOO NOISEY, JUST RIGHT.. I WILL SEND EMAIL FOR GRAPH
 

Aurora40

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1990 red on red ZR-1
Right off hand I know.

Mine, 90Callaway's, EricVonHa's, boostedmaxpsi, Ultra Slow's, 632c2's, and one or two more.
That'd be neat to know, especially what was changed to get to whatever power level the cars are at. Seeing your progression with your car was really neat, especially as you had several dyno runs along the way to document the progression.

Callaway1988, did they give you the corrected numbers also?
 

*89x2*

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Here are some Dyno Numbers from previous threads: :beer


Finished up another round of DynoJet runs last Sunday.

My best run was 650.51 rwhp at 4815 rpm and 730.49 rwtq at 4009 rpm. The boost on this run was 22.1 psi. The A/F was just about perfect on this run.

Using a conservative 15% drivetrain loss, these numbers work out to 765.3 hp and 859.4 tq at the flywheel.

My second best run was 609.09 rwhp at 4380 rpm and 733.19 rwtq at 4113 rpm. The boost on this run was 17.5 psi. The A/F ratio was too rich on this run.

The 650.51 rwhp is good enough for me. I am going to try to get the A/F a little better at the 17.5 psi level and then call it quits for now.



Steve

Ok guys, I finally got my dyno sheets uploaded after the recent exhaust work I had done in Nov. ( the sheets blew out the window @ 90mph :D )

Anyway you can see how much of a difference the large exhaust makes on a turbo car. The first sheet is my baseline dyno of which was a Callaway upgraded Wonderbar, no cats, AFPR and boost set a ~12.3lbs or 55" hg. Again the intercoolers get blazing hot after 2 runs.



The next dyno sheet is my current set up with everything the same add a 2 3/4" Power Effects exhaust system. As you can see the boost comes on A LOT faster with the larger exhaust....which explains the fart cans on the import turbo cars. Uncorrected numbers were 450+rwhp/600rwtq on a 70 degree day. I think these are more than accurate of what the car would do moving down the road with air traveling over the intercoolers.



The last sheet is a comparision of boost set at 10lbs or 50"hg compared to ~12.3-5lbs or 55-56"hg. If I close my PE mufflers down the motor feels really choked and I only get around 50-51"hg.






The next step is to do an Extrude Honed Accel TPI base and AZspeed/TPIS runners.

Dyno'd my '87 back in 2001; best run was 312.1 rwhp & 454.1 ftlb rw torque @ 3K rpm (this was with a small exhaust leak I had at the time). Since then I've replaced the exhaust and turbos, added a K&N filter, and made a few other mods ... should go see what the new numbers are :)

C4C5: IIRC my dynojet runs got me a best of 285rwhp and 436 lb ft of rw torque. Only mods are K&N filter, new Y-pipe w/o precats and Random Tech Cat. FYI.

Hi there,
Ok, the verdict is in, 288.7 horse and 451.3 ft lbs of torque. I could not get real 52 in ABS out of the turbos. Once I had to back off, because the gauge hit 55 and that is too much by Callaway standards.
After that, it only got to 50.
c4c5

The "Guess the HP/TQ contest" was close... verrry close. Much congratulations to 8388 who guessed the closest! :beer

The car did 341hp and 468 tq to the rear wheels. Not too shabby for a turbo car from the late 80's! The A/F ratio was very rich.. even at peak torque/boost the motor hardly went above 10:1. With a little tweaking I'm sure there's more in there... but it's staying where it's at for the time being.
 

*89x2*

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...more from others :cool


89x2-
We are not selling the Callaway car, the owner is, so we don't know how many people have asked about it. We're just hosting those photos for him as a gesture of customer service since he is a very good client of DTE with his other cars.

I managed to find those power numbers for the Callaway you were asking about. It made 412 RWHP/461 RWTQ on a Dynojet 248 in-ground chassis dyno. Ambient was 72* in the test cell and the car had two month old gas in it...

HTH's

Regards,
Phil Rickard, President
Dynotech Engineering, Inc.

Hi All,

Tim is right with his numbers. Back in 1995. David and modified a 1987 4+3 convertible. Dual the exhaust, K &N air filter, Ported the intake and exhaust side. Install a 52mm throttle body and turned up the boost to 12.5lbs with a single hi-flow cat for emissions. Results as follows with conversion to net figures:

Starting Net Figures Stock: HP- 366 and Torque- 508ft-lbs

HP: 438 @ 4500rpm
Torque: 582ft-lbs@ 3000rpm

Great little ride for the weekend warrior!

Take care all,
Stan
 

CALLAWAY1988

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Joined
Feb 26, 2004
Messages
82
Location
atlanta
Corvette
1988 CALLAWAY
Thanks for posting my graph.. a little computer challenged. I agree it is running lean. So I am interested in what you guys feel could be done to increase the fuel. I dont know how to test the microfueler and am not sure how much of an effect it has on the overall performance. Once I did twist that car tight enough to see 50+ on the vacuum gauge. I cant help but believe, if I could get some more fuel in it, the car would do better numbers.
 

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