Head and Cam Swap, 82 CFI

You know I really have no clue what the redline should be. Stock 2 bolt block, hydraulic flat tappet cam, 1.6 roller rockers, 1.437 dual springs, what should the redline be? I really don't know. What do all y'all think?
 
Id be guessing, but I would think 6000-6100rpm should be safe and reachable, with that engine configuration, its not so much the bottom end rotating assembly as the valve train component control and maintaining that stability thats in question here. your larger and heavier load valve springs should at least in theory give you some edge here! the average sbc engine easily handles 4000fpm in piston speed even with the stock cast crank and 3/8" bolt rods, but most stock valve trains are the limiting factor as they tend to become subject to valve float issues by 5800rpm-6100rpm
 
Thanks for weighing in, Grumpy. I'm used to the old redline from before the rebuild so when I get over 5300 I get nervous. I can relax a bit now :)
 
Picked up a miss at idle and a little popping at WOT, pulled the plugs and two were carbon fouled with the other six starting to show signs of buildup. I was using Champion RC12YC, turns out the heat range was too cold. Swapped to NGK's that are two stages colder than the stock heat range. Idle smoothed out and better power, no miss, no popping. I'll pull them again in a few miles to see if they are too hot or too cold. The learning continues...
 
The hotter plugs did the trick, and for a while I was having no issues, but now a new issue has popped up. The computer was pulling so much timing that it was almost undriveable. I disconnected the knock sensor to test a theory and driveability returned, with no knock from the engine. I tested by lugging the engine in OD, not a single ping. So I'm at a loss as to where to look for the noise that the sensor is picking up. Could it just be a bad sensor? The original is no longer available, so I am using an 84 Vette sensor in it's place. Any ideas? Without the sensor plugged in the engine runs and idles perfectly.
 
Looks like I may have spoken too soon. Tonite I had the same issue even without the knock sensor plugged in. Talked with Brian on the DC site as well, he gave me some things to check and told me to ask Phil about EFI systems available to replace the stock CFI on my car... More to follow, looking at fuel delivery next.
 
I ordered EBL Locker system from Dynamic EFI. It came recommended from a few 82 owners that have done the Renegade intake. Fully tunable system for the CFI and other EFI systems. I'll cover the installation and the tuning here once all the parts come in. I've replaced all the sensors except the knock sensor and I will be replacing that as well in the next few days. I've also ordered an 84 Corvette ESC module to match the knock sensor to eliminate issues with the ESC. I am adding an IAT with the new ECM to improve the performance of the EFI as well. The new tunable system will allow me to upgrade the engine further in the future, because as we all know, horsepower is addictive and what is enough today will not be enough tomorrow.
 
My Personal Favorite Spark Plugs/ Brands are ACCEL U-GROOVE Original Copper core Spark Plugs.

& Champion Original Copper Core Spark Plugs.

Champion spark plugs is what Mickey Thompson used in all his race Pontiac V8's 1959-63.
Got him to 406 mph on the Bonneville Salt Flats Running 10 miles Flat Out Each Way.
 
It's got AC Delco's in it for now, so far so good. Bob hooked me up with the EBL system we talked about, Brian. Should be here by Wednesday. I added an IAT sensor to the air cleaner yesterday. I'm gonna get this thing figured out and running right again.
 
I didn't know from our conversation on Digital Corvette over several nights you installed HOTTER HEAT RANGE SPARK PLUGS Drawman.
Very possible source of Pre ignition that leads to Detonation.
Especially with todays pump gas.
Ethanol gas is that Crappy and unpredictable .

For example the last 455 I had in my 1963 Grand Prix back in 1998 had just 8.2:1 Static compression with a Comp 280 Hyd Magnum Cam.
I had to run a AC Delco R42T spark plugs to prevent pre ignition detonation on 87-93 pump gas.
Pump gas here in Illinois was Shitty back then also.
Stock plugs were AC Delco R45 T.
3 heat ranges colder than stock worked perfect for that engine.
 
I started out with Champion RC12YC plugs. They fouled after about three weeks so I went with the hotter AC Delcos. Swapping back is not an issue, they are only one heat range different. What plug heat range do you recommend? Dart SHP Aluminum heads, 72 cc chambers, 200 cc intake runners, flat top forged pistons at stock compression height, approx 9.5 to 1 compression, 256/262 advertised duration cam (Voodoo, part numbers in the thread). I have very little experience here, so I'm always open to suggestions.
 
If it was me Drawman the Champions 12's would go back in.
20 gallons of Aviation 100LL in the tank.
Or 110 motor octane race gas.

:mrgreen:
 

Have you checked the intensity of the spark? Should jump 1/4" to 1/2" in free
air and be blue. Should also hear a pretty loud snap when the spark jumps.

It would also be a good idea to post some clear pictures with the plugs numbered
as to cylinder.

 
Yeah spark is loud and blue, lol. I'll get some pics up soon. These plugs haven't been run long at all. I haven't driven the car in a couple of weeks due to the issues with timing and fuel. The new system is supposed to get here wednesday, currently the interior is gutted and the computer is removed in preparation for installing the new ECM and ESC. "While I was at it" syndrome hit and I have ordered a few parts for the interior that I have been meaning to get to, but never have, so I'm loading up my wagon. Today I repaired the seat tracks that have been sticking and did a lot of cleaning while I had the seats out. Don't want to waste time while waiting for everything to arrive so I've been doing little jobs to keep my interest up. Before these issues hit at the beginning of January, the car ran great. Once I get this sorted out it will run great again AND be tunable. The new ECM was in the long range plans anyway, the timetable just got moved up a bit.
 
87vette81big said:
If it was me Drawman the Champions 12's would go back in.
20 gallons of Aviation 100LL in the tank.
Or 110 motor octane race gas.

:mrgreen:
Click to expand...


I can do the Champions easy enough, but the race gas may be a little harder to obtain, lol.
 
Update:

I got the EBL Locker system installed. It wasn't hard at all to wire up and flash. Did a few runs and ran what is called "VE Learn" to help trim up the fuel curve. I was still having the same issue as before, but not nearly as bad. Problem was, it only cleared up to a point instead of tuning all the way out. So I went and did a 10 min drive and datalogged it. The EBL software lets you playback datalogs in real time through the software. Timing was good, wasn't jumping around all over like it was, knock counts were much much lower, and none at idle and cruise, just at high MAP (over 80 Kpa) and WOT pulls. So naturally I start thinking fuel again. Pressure checked out okay at idle, but I was wondering if the pump was keeping up. 13 psi shouldn't be hard for a TPI pump to maintain, but ya never know...

I have two sets of spare injectors that I've cleaned and kept just in case. I wanted to eliminate the injectors as a cause, and it was a free test, so I pulled out the 6 month old injectors and put in a set of GM/Rochester original equipment injectors instead. The 6 month old injectors were still shiny, the older ones were clean, but not as shiny, lol. I lubed up the o-rings and installed the older injectors. I found the issue. Bad injectors. What little knock I was still getting is all but gone, last knock count was under 80. I did more "VE Learn" rides and watched the computer pull back fuel that had been added in earlier runs. NO stumbles, NO knock, NO WOT bogging. The fuel curve looks a lot better now, I had a few cells that were up to 100%, which is not a good thing, now all the cells are back to more sane settings. Now that I have this issue (hopefully) worked out, I can start refining the tune, work on the spark and AE tables as I learn what the engine wants. On the last ride estimated MPG was around 28/29 at 65 in 4th. Not too bad. I'm just getting started with tuning, but I'd recommend this EBL for anyone that wants to keep a CFI motor and still have the option to tune the motor.
 
454 BBC TBI injectors 1987-1995 vintage are supposed to fit all CFI Engines Drawman.
Larger #'s per hour rating.
 
Injector offset time.
Does the EBL Cover it ?
All fuel injectors continue to flow fuel after solenoid cutoff current.
Its in Milliseconds time on a paper graph.
Not all aftermarket replacement injectors are the same.
None ever advertise very important injector offset time.
 
EBL I think does cover injector offset time. Stock injectors on the CFI are different flow rates depending on position. The Front Injector is 68 lb/hr and the rear one is 67 lbs/hr. That's at 13 psi, higher pressure of course yields more flow. I need to research using the 454 injectors, since they would be the same flow rate on each side, it may require parallel plumbing with an external FPR. I'm not sure how much difference the 1 lb/hr between the injectors makes, but the engineers at GM had their reasons I suppose. I've heard it was done to compensate for the FPR being in the rear TB.

Now that I have the ability to tune, lots of avenues for upgrades are possible. It's never gonna be a fire-breather like a certain 70 T/A, but it'll get where I need it to get and now I can compensate some for today's less than perfect fuels. The 454 injectors sound fun :)
 
I just looked in the tuning parameters and there is an injector compensation offset table. It is set dependent on the voltage to the injector. I don't know the specs of the injectors I have, so for now I'm leaving this alone. The injector part numbers are 5233775 on the front Injector, and 5233770 on the rear. I have the flow rates, just not the offset time.
 
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