New cam

[ssyork]

I have a 1990 5.7L tbi with vortec heads and the GM performance tbi to vortec intake, 14"x4" open air cleaner on top, have done all the tbi mods from the 2nd gen site, am running my fuel pressure at max with an AC delco pump putting out 50-60gph@65-75psi, all on the stock chip with a 8747 computer. Also I do not run a cat and the exhaust has been opened up, but with stock manifolds. I really have no complaints on how it runs, but I want some more power so I bought the comp XE12-256-4 cam. specs here: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=91&sb=0
Also I have a BB tbi unit going on top. So to break the cam in should I leave the small block tbi unit on and then after break in start tuning with the BB tbi? Or should I put the BB tbi on for break in? Is there a tune I can get from somewhere to start with that is close for the break in? I am new to the tuning game, but with help form Norby should be able to get it figured out. Just not sure what to do about break in, I really don't want to flatten the cam. The hardware we are using is the Romulator AP1, with turner Pro R/T. Thank you for any help/suggestions with this.

 

[4xcrazy]

go roller, you'll love it.

 

[MNorby]

i gotta figure tuning my engine first but am starting to get it more figured out now so should be able to do your by then. curious to see what the concensous is on this topic too.

 

[dave w]

I have a 1990 5.7L tbi with vortec heads and the GM performance tbi to vortec intake, 14"x4" open air cleaner on top, have done all the tbi mods from the 2nd gen site, am running my fuel pressure at max with an AC delco pump putting out 50-60gph@65-75psi, all on the stock chip with a 8747 computer. Also I do not run a cat and the exhaust has been opened up, but with stock manifolds. I really have no complaints on how it runs, but I want some more power so I bought the comp XE12-256-4 cam. specs here: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=91&sb=0
Also I have a BB tbi unit going on top. So to break the cam in should I leave the small block tbi unit on and then after break in start tuning with the BB tbi? Or should I put the BB tbi on for break in? Is there a tune I can get from somewhere to start with that is close for the break in? I am new to the tuning game, but with help form Norby should be able to get it figured out. Just not sure what to do about break in, I really don't want to flatten the cam. The hardware we are using is the Romulator AP1, with turner Pro R/T. Thank you for any help/suggestions with this.

Not using a catalytic converter allows using "Zinc" oil additives. There are several "Race" oils that add zinc also. I actually use one pint of STP oil treatment in my non catalytic converter Buick on every oil change. STP oil treatment has the same zinc additive as the expensive race oils.

I went with a BB throttle body (using 350 Injectors) on my start up, but I installed a roller cam. I would use a BB throttle body (using 350 Injectors) with a flat tappet camshaft break in.

As for a .bin file, I think it would be safe to add "2" the Base Pulse Width (BPW). Adding "2" to the BPW will help keep the mixture a touch rich. Running a touch rich is better than running a touch lean.

The 8747 can use the same performance timing table I posted in my tread "Free 7747 350 Performance Timing Table" http://coloradok5.com/forums/showthread.php?t=275641 The .xdf file used makes a difference on how a timing table will look.

Changing the Timing Table changes everything, so only change the timing table if you can data log.

Send me a PM, we can exchange emails and .bin files if want? If we exchange a .bin file, we must "sync" to the same .xdf definition file! I'm using definition files from the TunerPro website.

dave w

 

[dave w]

I just looked on the TunerPro website for a definition file for the '8747 ECM ($4F), and could not find one. I found a ($4F) definition at Moates.net.

dave w

 

[ssyork]

Thank you for your input. I will be installing the cam sometime in the next month or so. i am also 4 linking the front, so shooting for a march time frame of being back on 4 wheels. I was told that the 8747 computer might have a better fuel table, so to use it. I do have a 7747 computer also though. I have the cam break in oil additive, which I found out is really just mainly the zinc additive like you mentioned.
Did you stay with the sb injectors or switch to the BB ones later? I will have to check with Norby as to what .xdf file we are using. We can datalog also. We just don't have a starting point other than stock and where not sure how that would work with breaking the cam in. I will get on the moates site tomorrow. Thanks again for your help

 

[dave w]

Thank you for your input. I will be installing the cam sometime in the next month or so. i am also 4 linking the front, so shooting for a march time frame of being back on 4 wheels. I was told that the 8747 computer might have a better fuel table, so to use it. I do have a 7747 computer also though. I have the cam break in oil additive, which I found out is really just mainly the zinc additive like you mentioned.
Did you stay with the sb injectors or switch to the BB ones later? I will have to check with Norby as to what .xdf file we are using. We can datalog also. We just don't have a starting point other than stock and where not sure how that would work with breaking the cam in. I will get on the moates site tomorrow. Thanks again for your help

I am using 65lb "Cop Car" 350 injectors in my BB Throttle Body.

I am using a TPI roller cam GM #[FONT=&quot]10066049[/FONT] with 1.6 roller tip rocker arms. The total lift with the 1.6 rocker arms is .443 / .459. There is no real way to compare roller vs. flat tappet camshafts, but the lift of the Comp Cam posted above is .449 / .456. The roller cam I am using with 1.6 rocker arms and the Comp Cam posted above, are similar in lift by a few thousands of an inch.

The Comp Cam listed above will make good, not excellent vacuum. Based on my experience, I would add some additional fuel (Base Pulse Width) to the stock chip program.

dave w

 

[MNorby]

I'm using the 42.xdf in tunerpro currently for my stuff (7747). I downloaded it from Moates

 

[dave w]

I'm using the 42.xdf in tunerpro currently for my stuff (7747). I downloaded it from Moates

'7747 ecm uses 42.xdf definition.

'8747 ecm uses 4F.xdf definition.

If I had only two choices '8747 or '7747, I would choose the 42.xdf / '7747.

dave w

 

[MNorby]

the 8747 doesnt have a ve adder table right, just the main ve table?

 

[eagle mark]

Not sure. But I talked to TunerPro last week and got an ads file for reading data if you want it. The 4f from Moates will work for the 8747.

Also to break in a cam I would use all known good stuff to get it to start and run and break in then start with BB TBI unit and tuning.

 

[dave w]

the 8747 doesnt have a ve adder table right, just the main ve table?

I agree, the 8747 does not have the VE Adder Table.

See the screen shots.

dave w

 

[eagle mark]

I agree, the 8747 does not have the VE Adder Table.

See the screen shots.

dave w

Does it not have a VE adder table or the guy who made the 4f not list the adder table?

Since I am hex illiterate I can not tell...

 

[dave w]

Does it not have a VE adder table or the guy who made the 4f not list the adder table?

Since I am hex illiterate I can not tell...

I only know what is in the definition file. I am not completely hex illiterate, but I am Hack illiterate.

I checked the TunerCat site for the Table List, no VE Adder with TunerCats.

Tables
ECM Switch Table
ECM Constant Table
Main Spark Advance
Base Coolant Temp. Spark Adv. Correction Vs. MAP
Power Enrichment Spark Advance Vs. RPM
Knock Retard Attack Rate Vs. RPM
Max Knock Retard Vs. RPM (in P. E.)
Knock Retard Recovery Rate Vs. RPM
Max Knock Retard Vs. MAP
Start Up Spark Advance Vs. Coolant Temp.
Start Up Spark Advance Decay Delay Vs. Cool Temp.
Start Up Spark Advance Decay Mult. Vs. Cool. Temp.
Main Fuel Table, % Volumetric Efficiency
BPW Vs. EGR Vs. Air Flow
Mean/Rich/Lean O2 Voltage Thresholds Vs. Air Flow
Power Enrich. Air Fuel Ratio Vs. RPM
TPS Threshold For Fast Power Enrich.
TPS Threshold For Normal Power Enrich.
Accel. Enrichment Vs. Differential TPS
Accel. Enrichment Vs. Diff. MAP
Accel. Enrich. Temp. Correction Vs. Coolant Temp.
Open Loop AFR Vs. Coolant Temp.
Open Loop Air Fuel Ratio Vs. MAP
AFR at Startup (Choke)
Choke Air Fuel Ratio Multiplier Vs. Coolant
Crank Air Fuel Ratio Vs. Coolant Temp.
IAC Steps Vs Coolant Temperature
Target Idle RPM Vs Coolant Temp.
EGR Spark Advance Vs. % EGR
% EGR Vs. Load Vs. RPM
EGR % Correction Vs. Load Vs. EGR Duty Cycle
TCC Load Limit Vs. Vehicle Speed

dave w

 

[eagle mark]

That makes me wonder more as the TunerCats shows some Knock parimeters and the 8747 has no knock...

 

[ssyork]

Thanks for the replies on this. Looks like I should maybe use the 7747 comp and save the 8747 for a back up. I was told that the same chip would work in both, just not as good in the opposite one. I think I will leave all alone to break the cam in, maybe hook laptop up and watch in case its lean. Then add the bb tbi and tune from there.

 

[MNorby]

Thats kinda what Joe and I thought, use stock setup and we'll watch how its running and if it starts going lean we can either bump up BPW or adjust VE table in the cells its in while in breakin RPM using emulator. What do you guys think would be better to adjust?

 

[dave w]

Thats kinda what Joe and I thought, use stock setup and we'll watch how its running and if it starts going lean we can either bump up BPW or adjust VE table in the cells its in while in breakin RPM using emulator. What do you guys think would be better to adjust?

My method is to adjust BPW first. I use the data log average BLM (math stuff) to get an average BLM betwen 126 ~ 130 before I adjust the VE table. The closer to a BLM of 128 the better. Sometimes it's impossible to get an average BLM of 128 without adjusting some of the VE table.

With a mild performance cam, my experience is the low RPM's of the VE table will be rich, and the high RPM's of the VE table will be lean, once the BPW is corrected to get a BLM's average between 126 ~ 130.

dave w

 

[MNorby]

Are you referring to break in or general tuning?
I'm just curious if we see it going lean on break in which table (BPW or VE table) should we adjust to get it into check for the 20 min of 2k rpm? After we have cam broke in I am fairly competent we can get it tuned.

 

[eagle mark]

For break in it would be nice to have an adjustable regulater. If it's lean turn up the presure and get the cam broke in. If you've got your tune close then it should be OK especally if your are emulating and can richen it up.