My Modified '82

[KANE]

ENGINE MANAGEMENT: Dynamic EFI EBL with TT-1 WB O2 sensor
ENGINE INTERNALS: Erson, .465″ in / .488″ ex, 224/234, 110 LSA
FUEL DELIVERY: Balanced TB units with 80lb injectors, VAFPR set to 15psi on idle / 20psi off idle, and a DCS Renegade Intake


Modified 1982 Corvette with EBL and .465" in/.488" ex cam | VetteTube

 

[Yoda]

Looks like RARE but it sure don't sound like RARE :eek

Looks as good as it sounds Nice very NICE!!!

Bud

 

[kpic]

Very nice looking and sounding.

It ought to go right quick also.

 

[jimbil208]

Hello Kane
I have a 1982 collectors edition and I bought a Dynamic EFI from Phoenixville, Pa about 3 years ago and I haven't installed it.

I plan to do it this summer. I am only replacing the EFI nothing else. Can you tell me if this unit will show better performance.

and if that is all I have to change to notice any difference?

Anything else to offer?

Thank You, jimbil208

 

[KANE]

Jimbil208- if you tune it... and you have a stock motor... yes, it will run better I believe.

However, I found having a wideband O2 sensor to be critical since there isn't a crossfire BIN that is readily available. Honestly, without it, I was struggling to get the tune down. It helps out a lot with WOT tuning- and it is very responsive for tuning everywhere else.

Where EBL shines - in my opinion - is with cams, heads, injectors, and fuel pressures not calibrated together by GM. EBL is not something you'll figure out overnight and end up with a killer tune after two hours. I spent a lot of time searching through threads on Third Gen.org and other sites. But it is well worth it- just don't give up.

Most of the struggle I had was the steep learning curve for tuning.

There are guys who are a lot better than me at this stuff- but anything I can help with I'm willing to offer. Example- I have an 85 Vette spark table in MS Excel. Should work for your crossfire since the 85 heads are the same as our 82s. Send me a PM and I will send it to you.

Aside from the spark table, I think the GM truck BIN would be a good start if you engine is stock.

 

[KANE]

Tuning is now done!

Below is a summary of the outcome using post/pre data log comparisons and OEM performance numbers obtained from the CAC.



A Few Notes on Pre/post: All data logging was measured and recorded pre/post with Dynamic EFI's "What's Up Display" software. Multiple data logging session took place in May of 2014 with 14.5psi fuel pressure, Compu-Cam .425”/ .440” cam, 65lb injectors, and a Renegade intake... and then again in January of 2015 with 15/20psi, .465” / .488” cam, Renegade intake, and 80lb injectors. Unfortunately, I do not have "bone-stock" datalogs as I did not install EBL Flash until after the Renegade intake and cam were already in the car.


Here is the complete summary…
Air & Fuel:

• Balanced OEM Twin Factory TBI units with anti-tamper plugs and welds removed
• Factory air box in place with fresh air door removed
• 31gph 1985 Corvette Fuel Pump in place of OEM pump
• GM Marine pressure regulator modified into VAFPR (15psi idle / 20psi off idle)
• 80lb injectors
• Dynamic Crossfire Solutions Renegade Intake

Engine Management:

• Dynamic EFI EBL Flash ECM
• TT-1 Wideband O2 sensor
• OEM harness re-pinned for late model connectors
• IAT sensor added to EFI harness

Major Engine / Driveline Components:

• .465" IN /.488" EX Erson cam
• Cast iron heads
• Factory 2.87 rear end gear
• 700R4 transmission
• Factory allow wheels 15x8 and 255/60/15 tires
• Factory suspension
• Factory exhaust with high flow converter
• B&M shift re-programming kit with OEM weights and purple and orange springs

Manufacturer's Crate Motor Dyno vs Stock Motor Comparison:

• 325hp @ 5,300rpm versus stock 200hp @ 4,200rpm- to put that into perspective… at 4,200rpm it is already pushing 260hp and still has another 63hp and 1,200 rpm to go before it leaves first gear
• 373lbs-ft of torque @ 3,600rpm versus the stock 285hp @ 2,800rpm- to put that into perspective… at 2,800rpm it is already pushing 350lbs-ft of torque and still has 800 more rpm and has another 23lbs-ft of torque left to go

Acceleration Post/Pre:

• Makes a 5,400-5,475rpm 1-2 shift on a warm transmission to make full use of the horsepower curve- prior to resetting the governor, 5k rpm 1-2 was the norm on a warm transmission
• Leaves 1[SUP]st[/SUP] gear at 47mph- 4mph faster than with just a Compu-Cam and Renegade intake
• Takes up 2[SUP]nd[/SUP] gear at 56mph @ 3,500rpm- 8mph faster than with the Compu-Cam and Renegade intake @ 3,000rpm
• Leaves 2[SUP]nd[/SUP] gear at 80mph @ 5k rpm- 5mph faster than with the Compu-Cam and Renegade intake
• Takes up 3rd gear @ 81mph @ 3,200rpm- versus 3,000rpm with the Compu-Cam and Renegade intake
• Buries the speedometer needle within the first ½ second of third gear- at the 9 second mark of a rolling start. That’s a full two seconds faster than the Compu-Cam and the Renegade intake
• Rolling start (~5mph) to 60mph is 5.3 seconds. The best time with just the Compu-Cam and Renegade intake was 6.6 seconds. It is now a full second and 1/3 faster than tuning on the Compu-Cam and Renegade intake alone- and almost two and a ½ seconds faster than stock 0-60mph
• Rolling start (~5mph) to 80mph is 8.3 seconds. The best time with just the Compu-Cam and Renegade intake was 10.5 seconds. That’s a full two and 1/5 seconds faster than the Compu-Cam cam and the Renegade intake alone- and almost six seconds faster than stock 0-80mph

 

[KANE]

Attached is a datalog of the pre/post... this is the closest thing to a dyno of results.

For reference, the "post" results are superimposed upon the "pre" results.

The .465 cam accelerates a lot faster than the .425 cam- and with the 400 or so rpm increase on WOT, the dividends are huge at the point in which the car shifts from first gear and into second.





Also a point to note... the "post" test was run in open loop. So while the PE values were about dead on, there was still some adjustment needed in the lower KPAs off wide open throttle. Also, the Compu-Cam was running closer to high 12s and low 13s for AFR at WOT while the Erson cam likes to run in the lower 12s.

 

[KANE]

I wanted to create a sleeper...


So it was very important to keep the car looking as close to factory as possible. I have tried to retain as much of the OE pieces and parts under the hood as I could.

The most obvious change is the removal of the fresh air door to assist with breathing. Otherwise, everything looks to be in order. The AIR system is capped off in the photo below so that I can get the most accurate readings I could get with the wideband O2 sensor while I was tuning.

VAFPR:
The hose routes through the thermo switch on the air box.

Close up of the VAFPR mod...

IAT:
I added the IAT to the underside of the air box on the snorkel so that I could clear the fuel line that runs between the TBs.

Balanced TBIs:
Spare wood, a printed out ruler, and $3 in hose and we have a tool!

Renegade Intake:
Yes... this intake launched a thousand flame posts across many a message board, but it really does fit under the hood quite well. And it works with a bigger cam and tuning.
This is an older photo that dates back to summer 2013- but thought I'd post it since it is part of the list of mods.

 

[82ColEd]

Thanks for putting this all together, i see it as a great reference, if one decides to go that route..

Stefan

 

[KANE]

ThirdGen.Org and GearHeads are two forums where there are a lot of people who do significant tuning.

I am still very, very much a novice at this. But I do want to share what I've done as well as things I have learned along the way. What I will say is that EBL is great for many reasons, but the biggest reason is the nearly complete flexibility in tuning that I have with resepct to sclars, tables, and word options. Also, I don't think I could have afforded the amount of time I spent tuning if I paid someone else to do it.




A few observations, thoughts, things I learned, and things I that worked for me...

• Components:
  • One of the biggest headaches was a bad harness connector for the wideband O2 sensor on the controller side. That gave me absolute fits!! The contacts weren't crimped down enough or something and it caused the sensor to never come out of warm up mode. I thought my 32 year old exhaust system was leaking and could never get more than a 14.5-14.7 reading. Consequently, I had a terrible time trying to tune PE mode. Using the NB sensor worked fine for tuning everything but PE, but it doesn't work for PE. How did I find it? I spoke with Dynamic EFI and shared some logs. They suggested to send back the unit and have them check. As I was pulling the connector back through, it came off and the leads were still twisted nicely for the crimp. Dynamic EFI took care of it- they are great to work with and have the best service of any small business I have ever seen. My observation is you will drive yourself crazy tuning if your wideband isn't operating properly.
  • I had a TPS sensor that malfunctioned and a couple of IACs that worked somewhat. They worked- kinda- but not perfectly and not all the time. My thoughts here are that I should have looked at them like they were wear items when I started and simply replaced them ahead of tuning. I spent less than $150 on those three parts and while replacing them took only minutes, it took hours to figure out they weren't running properly because the problems were subtle. Such as an intermittent flat spot on the TPS readings or the intermittent sticking of an IAC.

• Routing & re-pinning the harness: This was fairly easy, although many folks cringe at this. What I found helpful was to create a color by color crosswalk for moving the CFI leads into the late-model GM connectors. I used wiring schematics (1982 Corvette) and then a TBI pin-out schematic and tested about a quarter of the wires just to make sure what the schematics showed to be the sensor was in fact correct. I also found that I could run the IAT lead that I added along side the OEM harness as it made its way from the rear of the car to the bulkhead and up to the air box. I also ran it through the OEM conduit loom. Advance Auto sells replacement pigtails for less than $20, so this was an easy "no waiting for UPS" kinda project. I also ran the TT-1 wideband power leads along side the OEM harness and even grounded it under the hood to the same grounds the CFI harness used on the block.

• Notes on Tuning:
  • 112 LSA Cam, low RPMs, AFR, and open loop/closed loop idle: I am running a cam with a little less overlap. I also can run a richer AFR without fear of destroying the catalyst with my exhaust configuration. Consequently, I can run a little richer AFR and can tune around the LSA. It is my understanding that at lower RPMs the LSA makes a bigger difference and can make tuning somewhat a challenge. So I adjusted the commander AFR and can run the engine at idle in closed loop- and yes, it runs quite well with no codes or a rough idle. It also helps that my idle speed is about 750rpm (rolls between 700-800rpm) and I have adjusted the minimum idle and balanced the TB units for a minimum idle of 600rpm. My AFR at WOT is between 12 and 12.3 to 1 and that is waht the cam and intake seem to work the best with in my testing and tuning.
  • VAFPR: I didn't want to use an Aeromotive piece because I wanted the car to look as close to stock as possible. The housing for my FPR is actually from a GM marine application where there is a discharge tube that would allow for any leaks to drain into the intake. The housing is sealed and by applying vacuum to the unit, it can now be used as a VAFPR. By lobbing off a portion of the tube and removing a locating ear that is not needed by the CFI TB unit, I was able to rotate the housing 90 degrees and then use it as a VAPR. With this set up, I have 15psi at idle and then off idle it jumps to 20psi... which is perfect for what I need it for. Best of all, it is hidden inside the OEM airbox and completely unnoticeable!
  • IAT: I needed to add an IAT sensor for the EBL system. I also needed a place to mount it and I wanted it to be out of sight. By locating it in the snorkel on the underside of the airbox, it too is out of sight.
  • Idle speed: I started with a GM truck BIN, and the trucks run a fairly low idle speed. So I adjusted all of the tables dealing with idle to make sure it idled where I wanted it, which meant that I needed to adjust the idle speed at different temps to bring it up higher than what the original bin called for.
  • SA Tables: I was able to find the SA table for an 86 iron headed Vette under a different XDF file... and then copied & pasted it into MS Excell... which was a perfect starting point for my tables. The '86 Vette with iron heads uses the same heads as the 82 & 84 Vettes. I also pulled the spark up on the PE adder tables to get it to 36 degrees (per my engine builder) at WOT. I added a little more spark earlier than what the 86 SA table called for and that helped a lot too. Most importantly... I am not getting any knock with the tables I am using.
  • Lean Cruise & Async Mode: I went ahead and disabled lean cruise as well as Async injector mode. I don't feel that I need lean cruise and disabling keeps it from the slight bucking at 1200rpm in overdrive while cruising as it would go into or out of lean cruise. The transition mode to Async mode wasn't as smooth as I wanted where the ECM was struggling a little bit to keep up with the change, but since I don't need the extra fuel as part of a fueling strategy that Async would allow for... it works fine without it. From what I have read, getting a good transition from sync to Async is pretty difficult. Disabling async would likely really benefit a dual plane, but on my intake it's only a small improvement because both injectors serve a common plenum. My point here is that it helps with my intake and fueling needs, but don't expect a big difference.
  • BPC & VE: This is an area that I had to adjust as I had plenty of duty cycle (less than 85%) but ran out of VE (100%). I set the BPC for my fuel pressure and then had to increase the BPC table while lowering the VE tables. RBob talked me through how to do this- and it worked quite well. Ideally, I would have gotten readings for BPC at the different KPAs, but this technique has worked for me. Now, my overall VE doesn't get past 87% at WOT on the high speed tables (at 4,400rpm) and my injector duty cycle is still only 80% at 5,450rpm at WOT.
  • Overall adjustments: I think when all was said and done I have made changes to 30 some odd tables, sclars, and word options. I can also tell you that I have not been able to find a BIN ("chip" programming) or XDF (definition file for a given system) for the original crossfire. So these changes are relative to what you'd see when using either a truck BIN or 5.0 Fbody BIN. Some tweakss were harder to identify (such as deciding what temp to set closed loop based upon engine performance or setting the shift point on the tranny) while others were easier (identifying a need for a better SA table was very easy). I also can't reiterate how beneficial resetting the 1-2 shift point has been- the OE shift point was just too low for this motor. Every car is different, but getting the 1-2 to happen just after peak HP has made a world of a difference in the way the car feels.

But it has been well worth it! Hope this helps someone who is on the fence about what can be done with their car.

 

[jimbil208]

Thank you very much for the information. I will put it to use this summer.

Right now I am trying to organize everything

jimbil208

 

[KANE]

Well... I think I have the tune pretty much nailed down. Over the fall and winter, I spent some time nailing a bunch of little things down. Such as tweaking some of the CTS tables and multipliers for when it is cold / hot, adjusting different settings, finally had a dedicated bung welded in for the WB, etc. I also added in some spark in a couple places- such as the lower MAP areas between 1k and 2k rpm. I also added some spark to a couple of areas between 60 and 80 KPAs too. That has seemed to help a few things around transition between moderate cruise and moving into WOT.

Oh... and I recently added larger bore TBs.

I am at 49mm- so I am 3mm over stock and 3mm shy of the 2" TBs that many folks have used with cams that are larger than mine. Thought I'd split the difference as I can always go larger... but not smaller... once the boring starts. I don't want to lose velocity and hurt my low end since I have a 2.87 rear end, so the 49mm should flow high 600s in the CFM department. That should compliment my cam nicely.

I've been looking through logs at my MAP readings and thinking about how I may be running out of breath a little between 5-5.5k rpm. I was dropping to about 92/93 KPAs between 5-5.5k and now I'm at 93/94 in that same area. I still have a bit of a restriction with the OEM airbox and so I am going to hack up a spare air cleaner base and try to get a little more air from the bottom of the assembly.

Adding 3mm more has helped along with getting the TBs machined for bushings on the throttle shafts. The off idle to 2k rpm area benefited greatly from getting the TBs done. When I crack the throttle... it lunges- and the nose jumps up.



As an aside... MAXBORE will bore your CFI TBs. When I decided to get the TBs bored, I had a lot of difficulty finding someone to do this as many of the folks who used to have simply stopped. Maxbore will bore anything - from TPI to CFI as well as LSx and imports.

Attached are a couple of photos. The first shows the difference between an OE TB and my bored TB. The other is of both of the bored TBs.

 

[Zero]

82 Crossfire

I love what Kane has done. In fact, I will attempt to follow closely behind. With one minor exception - heads.

My 82 is a dog. And my dream of building a Factory Five Cobra has disappeared - Reality is, a Cobra is beyond my budget.

So, updating my '82 has started. With
The Renegade
The EBL engine management computer
An '85 fuel pump
Heads - Probably Skip Whites ProMaxx 200 cc.

Maybe I will put in a 427 SBC stroker. But that's for later.

My goal with the "somewhat" stock motor is 300HP - with a stroker it bumps up to 400...

 

[KANE]

My focus the last few months has been around the improvement.

Fuel pressure is good... spark tables are good... VE was good. All the major stuff is good.

No, now it's down to the small things.


Ah.... but the small stuff is important too- because enough of them added together makes a big difference.

IAT/CTS Blend Filter
I have the IAT mounted on front of the radiator in the air stream just ahead of the fresh air chamber entrance. This has taken me a while and a lot of notes to understand the % split needs... but it seems to be a lot more consistent in terms of measuring the air as it adds very little (or takes away very little) on cruise once it is warmed up. Basically, at idle it is pointing more to the CTS and then points almost 90% to the IAT once it is at WOT.
GmSec %OfCTS
0 39.61
16 31.76
32 28.63
48 26.67
64 25.1
80 23.92
96 22.75
112 21.18
128 20
144 19.22
160 17.65
176 16.47
192 14.9
208 12.94
224 10.98
240 8.63
255 5.1

O2 window for closed loop
Idle in closed loop runs 13:8 when on the rich side and then right about 15:1 when lean- but hovers mostly with a roll between 14:1 and 14.7:1 since it is an automatic and will benefit from a slightly richer mixture since it has load in drive. So, I am running the following settings for idle:
Mean R/L: 620.62 mV
Rich: 651.00 mV
Lean: 607.60 mV

INT Mean, Rich, and Lean
Meanwhile, when in cruise or decel I am running the following settings across all MAP values:
INT Mean: 642 mV
INT Rich: 672 mV
INT Lean: 616 mV

IAC - TF Gain, Delay Filters, and Decay Delay
I've massaged these a lot to get a really crisp off-idle throttle response. The throttle is very responsive now.

AE
I've found that I don't really need a whole lot of AE. My AFR stays where it should and then it runs quite well, with a burst of momentary fuel that brings it to to a lower AFR when the pedal is hit.

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Closed Loop: Cruise and Idle
Yes- I have the tune squared away enough that I can run in both modes in closed loop. This took a lot of tweaking with the INT O2 settings, the throttle follower settings, and AE... but wow- it's running great with only a drone during cruise and then no bucking at low rpms in gear!


I really love how it is running!

 

[kpic]

I wanted to create a sleeper...

Kane,
A sleeper was my thought also. After a very naughty life with cars; my thought what folks listen for the sound of headers, cam and the whine of a diff. So how about a stock sounding C5?

https://www.youtube.com/watch?v=qoNvL6Xx2UY&list=PLHVqn4aIC3ywkxwkL31l8mQnkMxbpiwJD

She said I hear the blower and broke my heart. :L

I know it sounds about as stock as yours does. At the end of the day; the reality is there isn't any such thing as a sleeper.

That being said, my compliments to a beautiful example of a sweet sounding Corvette.

 

[KANE]

A couple of videos...

IMG_1264_zps5yqxvarm.mp4 Video by Johnny-s_Shark | Photobucket

revs_zpsz6becgdr.mp4 Video by Johnny-s_Shark | Photobucket

 

[KANE]

I kinda needed the gauges "updated" to reflect the new red line. I also thought while I was there I'd update the speedometer too.

The picture below is in another thread- but thought I would share the before & after here.



EDIT: LED replacement bulbs are the way to go! They are a lot whiter (and brighter) than OE bulbs in terms of the color. So, I've upgraded all of the bulbs inside the car to LEDs.

 

[KANE]

Key highlights for modifications and the calibrations settings...

Thought I would share these as well.


The major pieces of the tune are pretty much set now as far as I am concerned- VE, SA, O2 Mv, etc- since I haven't had any big swings in % on VE learns in a couple of months.


Again, all of these are set for the .465" IN / .488" EX cam, 20lb VAFPR, 90lb injectors, Renegade intake, 85 fuel pump, and production iron heads.

 

[KANE]

More on IAT placement...

In a speed density system, the IAT plays a critical role in calculating the density of the air coming in and how much fuel is needed.

A challenge I was running into a few months ago was with getting the IAT/CTS blend just right and compensating for using the fresh air chamber as the source of air coming in. In fact, I was getting heat soak that was throwing the mixture calculation off by locating the IAT in the airbox. That meant it would run lean (cooler air temps & denser air) in the morning and rich in the afternoon (warmer air temps / longer running & less dense air).

At idle, low RPMs, and low speeds I founded I needed to be a little more biased to the CTS than the IAT. However, at wide open throttle and pulling in more air (GMsec), I found I needed to be more biased to the IAT. This is important because the IAT is involved in the calculation of the air density... which is critical to getting the mixture right.

I also found that as the oil temp warmed up, I needed to adjust the multipliers for increasing the % added to the overall fueling calculation between 100* F and 180* F for the coolant. 180* F is when my thermostat opens up and is about when the oil is fully warm. I mention the oil temp because that's when the block is fully warm- and I think that plays into the density of the air charge, fuel lining the intake walls, and potentially atomization of the mixture itself. My sense is that on a crossfire intake the lack of an air gap (insulation from heat) and the large plenum (surface area) creates conditions where it needs higher %s in the multipliers until it is fully warm.

As an aside, without an IAT GM was using the CTS exclusively in the chain to determine the air density. That leads me back to the idea the water passage under the intake was critical to getting a steady state for calculating mixture consistently.

I tried a couple of places before settling on mounting it by the vacuum reserve canister. I've already mentioned the air box as a place that didn't work due to heat soak.

Here are a few more:

• Hood / opening for the fresh air chamber: While this would seem like a logical and ideal place to mount the sensor, it too was prone to heat soak as the bracket would warm up and then warm the sensor. It wouldn't cool off fast enough and react to the changes in temperature as the higher volume of air was denser and cooler.
• Headlight actuator supports: I found that it would get heat soak from mounting by the headlight actuators themselves as they would get warm and transfer heat to the sensor. Same problem as above... not quite as much heat transfer, but still enough to throw things off and not react fast enough.

By positioning the IAT under the headlight actuators by the vacuum reserve canister, it is measuring the ambient air temperature that is getting sucked into the fresh air chamber without heat soak.

Had I been using the snorkel under the hood without the chamber or running open elements, I would have likely keyed off the CTS more heavily as it would be sucking hot air in.

The fresh air chamber really works! I can see that by the bias needed between the CTS and the IAT.

Summary: I am biased to the CTS at lower speeds by about only 35% idle (low demand; low Gm/Secs) and then at about 11% at wide open throttle (at max Gm/Secs).

 

[kpic]

Kane
I believe you'll enjoy this:
If it rolls, floats, flies or shoots, runs on gasoline or gunpowder, goes fast, shoots a big bullet, and makes lots of noise, thus producing torque and recoil, it's cool.
But if it's a ball, made out of leather or inflated with air, that's hit with a bat, racquet, or club, used in a game played on a course, green, or court by yuppies, Democrats, or liberals - forget it.

If you ever get over this way let us know.