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Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

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Old 05-25-2010, 09:07 PM
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Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Well, usually very agaist dyno's but new place opened not far from house. Talked with guy who was cool and pretty cheap..
Car had been feeling sort of dissapointing since, had a conservative tune in with only 32 degrees timing.
-First pass 377 hp at 5500 - 14.5 air fuel
-Second pass added 3 lb pressure and jumped to 419 at 5600 or so. 13.8 air fuel.
-third pass added 10% to pe enrichment, jumped again to 434 at 13.5.
- 4th pass added another 15%, jumped to 451 @ 6k, 13.2 air fuel.
- 5th pass added more to PE enrichment no change at all.
- 6th pass added 4° TIMING TO 36, made 463 @ 6100
- 7th pass added another 2° to 38°, made 468 @ 6100

Pretty good on 93, hope to hit track Thursday, but weather is looking bad.

Made more than I expected, expected 450ish.. Seems that injectors refuse to open any longer than 7.34ms??? Last three changes they maxed at 7.34 and stayed there - Something with code?
I also know the Miniram is now a restriction only flowing 283, I suspect with a single plane I will gain 30-40 HP and 1000 rpm.. Looking at data, I started pulling vacuum at 5000 rpm. Makes peak TQ somewhere around 4k it seems at 465 and stays very flat to 5200..
Old 05-25-2010, 09:30 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

can you add more fuel pressure to compensate for the injector issue? Things like this are why I'm glad I have a wideband and a carb in my car. In fact my old vic jr pulled vacuum on the motor above 6000, hoping the huge ports on this new super vic won't do that, they are probably 20% larger I'd imagine.
Old 05-25-2010, 11:09 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

13.2 is still slightly lean. A good safe range should be 11.9 - 12.8 at WOT

So your 'dyno tune" netted you 91 HP. That's not a bad increase for some basic changes. Need to figure out your injector problems. I don't deal with EFI. Perhaps bigger injectors are required.
Old 05-25-2010, 11:21 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

most tunes are set for 9.99ms to be max PW, did you max out your VE tables?


I did that on mine and ended up raising the BPC to compensate..
Old 05-26-2010, 12:46 AM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Do you mind posting specs of engine such as size, what AFR heads you have, possible flow numbers if you flowed them after porting, and cam specs or round about if you dont want to fully disclose them to the public. Nice numbers and nice increase in a days work!
Old 05-26-2010, 10:36 AM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Originally Posted by Purple82TA
most tunes are set for 9.99ms to be max PW, did you max out your VE tables?

I did that on mine and ended up raising the BPC to compensate..
Ve is maxed out at 99.9, you said you raised the BPC? Dont recognize the abbreviation, thanks.
I assume if I lower the inj constant it should fool the ecm to allow longer PW.


To answer some other question, I can raise the FP to compensate but already at 55lbs and using 42lb injectors.. I may raise some more for a quick fix but will need to fix the other issue. They are not going static yet, only around 85% or so I guess at 7k, so lower rpm will have much more time. Found out it is a problem in code with maxing out the Airflow which will cap you at a given Pulsewidth based on inj constant setting and cylinder volume. There is a patch for that I need to figure out.

Combo is 406, AFR 195's ported to 210 flowing 310 now. Mini Ram, Ultra Dyne Solid Roller 250s @ .050 on 110lsa.
Old 05-26-2010, 11:47 AM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Originally Posted by 87_TA
Ve is maxed out at 99.9, you said you raised the BPC? Dont recognize the abbreviation, thanks.
I assume if I lower the inj constant it should fool the ecm to allow longer PW.


To answer some other question, I can raise the FP to compensate but already at 55lbs and using 42lb injectors.. I may raise some more for a quick fix but will need to fix the other issue. They are not going static yet, only around 85% or so I guess at 7k, so lower rpm will have much more time. Found out it is a problem in code with maxing out the Airflow which will cap you at a given Pulsewidth based on inj constant setting and cylinder volume. There is a patch for that I need to figure out.

Combo is 406, AFR 195's ported to 210 flowing 310 now. Mini Ram, Ultra Dyne Solid Roller 250s @ .050 on 110lsa.
I'm still using 730 ecm on my 383 it made 421hp with a loose converter, GM847 cam with 42lbs injectors and the duty cycle was 76%. I know you have a relocated IAT sensor with the mini ram, I know I did when I had mine. You need to modify your Inverse MAT Term Lookup Delta Multiplier vs. Airflow table to correct your PW. Here is the thread you need, scroll down to post #10 and change everything in the table to match what's in the attached table. Not only will the AFR reflect changes made to PE vs. RPM table at WOT your VE table will need to be modified some to get your BLM's in check, no biggie.

https://www.thirdgen.org/forums/diy-...t-weather.html

You can use TunerCat or TunerPro it doesn't matter. When you change this table your fuel pressure does not have to be 55 psi. I would change it to 48 psi before doing any tuning after you fix the above table and 42 lbs injectors should be fine.
Old 05-26-2010, 01:10 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Originally Posted by zz17iroc
I'm still using 730 ecm on my 383 it made 421hp with a loose converter, GM847 cam with 42lbs injectors and the duty cycle was 76%. I know you have a relocated IAT sensor with the mini ram, I know I did when I had mine. You need to modify your Inverse MAT Term Lookup Delta Multiplier vs. Airflow table to correct your PW. Here is the thread you need, scroll down to post #10 and change everything in the table to match what's in the attached table. Not only will the AFR reflect changes made to PE vs. RPM table at WOT your VE table will need to be modified some to get your BLM's in check, no biggie.

https://www.thirdgen.org/forums/diy-...t-weather.html

You can use TunerCat or TunerPro it doesn't matter. When you change this table your fuel pressure does not have to be 55 psi. I would change it to 48 psi before doing any tuning after you fix the above table and 42 lbs injectors should be fine.
Its an issue with the ecm and calculated max air which will put a cap on pulse width on what I can understand.. There is a fix for, I have a thread on Prom board that discusses it. I do not even use MAT, I disabled mine years ago - I seemed to get more consistant performance without.. Thanks for help.
Old 05-26-2010, 01:23 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

What mask are you using?
Old 05-26-2010, 02:39 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Still some solid numbers. This car should fly man but then again, your old combo was probably in the 450 whp range anyway based on its trap speed. maybe this car will touch 130 on motor, especially if you get the injector pw figured out and are able to hit mid high 12's to 1 air fuel and find another 10-20 hp.
Old 05-26-2010, 04:41 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Originally Posted by Orr89RocZ
Still some solid numbers. This car should fly man but then again, your old combo was probably in the 450 whp range anyway based on its trap speed. maybe this car will touch 130 on motor, especially if you get the injector pw figured out and are able to hit mid high 12's to 1 air fuel and find another 10-20 hp.
I hope so, I may see tomorrow weather permitting.. I figured the other combo was 430's from my calcs - I would be very happy hitting 130s but more expect 128, I would not even expect that till better weather.. You should try the place I went to - I was there about 3 hrs and only charged me $120 and let me have control of the dyno. Real cool place! I am very anti Dyno, but glad I went - I have seen to many 500 rwhp cars do nothing.

I am looking forward to seeing a 700hp turbo car do something soon though!
Old 05-26-2010, 04:48 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Originally Posted by 87_TA
Its an issue with the ecm and calculated max air which will put a cap on pulse width on what I can understand.. There is a fix for, I have a thread on Prom board that discusses it. I do not even use MAT, I disabled mine years ago - I seemed to get more consistant performance without.. Thanks for help.
It should still fix your issue. I'm saying the same thing RBob is saying in DIY tuning forum. I had the same problems you are having until I made those changes.

By the way your car is making some good numbers!
Old 05-27-2010, 11:12 AM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Originally Posted by zz17iroc
It should still fix your issue. I'm saying the same thing RBob is saying in DIY tuning forum. I had the same problems you are having until I made those changes.

By the way your car is making some good numbers!
Thanks for the assistance, I did what was suggested in the bin by changing the hex address. I have not tested yet, would rather get some passes today with knowing where afr is.. It seems what you said would work as well and maybe easier.
What I have figured right now, with PW of 7.34 at 53 psi I am at 13.1ish A/F. When fixed I think at 48 PSI I will need PW of 8.1 to match same A/F. That seems to make sense in my limited math skills. So after today I will likely implement the bin change and start remapping..

Thanks for compliment, I feel 500 is not out of touch when new intake is on.. Once I get some good base lines I will probably spray again.
Old 05-27-2010, 12:48 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Originally Posted by 87_TA
I hope so, I may see tomorrow weather permitting.. I figured the other combo was 430's from my calcs - I would be very happy hitting 130s but more expect 128, I would not even expect that till better weather.. You should try the place I went to - I was there about 3 hrs and only charged me $120 and let me have control of the dyno. Real cool place! I am very anti Dyno, but glad I went - I have seen to many 500 rwhp cars do nothing.

I am looking forward to seeing a 700hp turbo car do something soon though!
What was the name of the dyno place? 3 hrs for 120 is a steal! I was on a dyno for 1hr 15min and spend 150 i think.

How light is that car? I was at 400whp and 3450lbs and trapped 119 in the July weather. I would have figured you were around same weight and in the 440-450 range. I will be home June 3rd and will try to head out to the track to get some more passes and work the tune abit more. You should come on out and line up in the street car lanes

Are you going with a single plane? Which one? Is someone porting it? I think I need to get mine opened up.
Old 05-27-2010, 01:05 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

With the numbers your putting down now, I wouldn't be surprised if you see 500hp with a single plane. The thing about the mini ram is it has poor air distribution, the front four cylinders get more air than the back four cylinders due to TB location. When I had my mini ram the back four cylinders were always coated with fuel residue and darker than the front four. You could buy a injector controller like the one Accel sold years ago to control individual injector PW, but the fact still remand that poor air distribution means loss of power. When I went to a single plane the throttle response was cleaner, car revved quicker, and you could feel the car pulling harder even at 6500rpm. So it should do really well with your set up.
Old 05-27-2010, 01:27 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

The miniram just needs reworked for more flow. they can be heavily ported/modded to flow over 350cfm but you still could have the distribution problems. A single plane should be better with its center feed plenum but even box stock single planes will benefit from a good port job since the runners are not all even shaped. 1989GTATransAm flowed a victor type carb single plane and it had alot of variance between runner to runner, from outer cylinders to inners. Just something to consider.
Old 05-27-2010, 02:12 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Originally Posted by Orr89RocZ
The miniram just needs reworked for more flow. they can be heavily ported/modded to flow over 350cfm but you still could have the distribution problems. A single plane should be better with its center feed plenum but even box stock single planes will benefit from a good port job since the runners are not all even shaped. 1989GTATransAm flowed a victor type carb single plane and it had alot of variance between runner to runner, from outer cylinders to inners. Just something to consider.

Thanks guys,
I assume I will have better driveability with a single plane also - the car seems and has always had issues cruising at 2000 - just not very smooth. I believe its due to air stalling out at low speed due to the 90° turn.. I have tried fuel and timing in either directions in extreme with no change, spent an entirs day dedicated to just that with 0 change.. Runs good just not real smooth.
Old 05-27-2010, 04:00 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Probably not enough plenum volume but could also just be air distribution issues. Then again you do have a big cam, maybe it just doesnt like 2000 rpm for cruise?


What was the name of the dyno place?

Last edited by Orr89RocZ; 05-27-2010 at 04:05 PM.
Old 05-28-2010, 11:59 AM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Originally Posted by Orr89RocZ
Probably not enough plenum volume but could also just be air distribution issues. Then again you do have a big cam, maybe it just doesnt like 2000 rpm for cruise?


What was the name of the dyno place?
The cam actually drives better tahn the other it seems, I can lug down to 1400 or so in 6th and cruises nice.. Its just right at 2k I can not fix..

The place is called Pittsburgh Dyno, about 15 minutes from my house. What was cool is having free reign of it and you drive and control the button.

Hit the track, nothing impressive many tune issues, will follow up later
Old 05-28-2010, 12:13 PM
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Re: Just got the car dyno'ed after porting AFR,s - Dissapointed and happy.

Oh ok, i know of that place. Havent been down that way but I've talked to the guy before. He had that 9 second civic hatchback I believe
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