Head and Cam Swap, 82 CFI



Re: Head and Cam Swap, 82 CFI

Postby Drawmain » October 14th, 2014, 7:37 pm

Thanks for the updated simulation. And thanks for all your help through the process!
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Re: Head and Cam Swap, 82 CFI

Postby grumpyvette » October 14th, 2014, 7:42 pm

your welcome, it will be interesting to see the numbers if you get it dyno tested, its sure to be an improvement over the factory numbers
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: Head and Cam Swap, 82 CFI

Postby Drawmain » October 19th, 2014, 10:34 am

I did a wot run yesterday. The car pulls hard all the way up to 5400 rpm where I got out of the throttle. It put a big smile on my face! It still had more past that, too.
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Re: Head and Cam Swap, 82 CFI

Postby Indycars » October 19th, 2014, 11:40 am


The best part is you can do it over and over and over and....... !!! :P

What do you expect your redline to be?

Rick
Too much is just enough!!!

- Check Out My Dart SHP Engine Project: viewtopic.php?f=69&t=3814
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Re: Head and Cam Swap, 82 CFI

Postby Drawmain » October 19th, 2014, 11:58 pm

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?
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Re: Head and Cam Swap, 82 CFI

Postby grumpyvette » October 20th, 2014, 8:59 am

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
IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
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Re: Head and Cam Swap, 82 CFI

Postby Drawmain » October 20th, 2014, 7:32 pm

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 :)
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Re: Head and Cam Swap, 82 CFI

Postby Drawmain » October 27th, 2014, 5:37 am

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...
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Re: Head and Cam Swap, 82 CFI

Postby Drawmain » January 21st, 2015, 8:05 pm

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.
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Re: Head and Cam Swap, 82 CFI

Postby Drawmain » January 22nd, 2015, 7:09 pm

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.
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Re: Head and Cam Swap, 82 CFI

Postby Drawmain » February 14th, 2015, 1:15 am

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.
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Re: Head and Cam Swap, 82 CFI

Postby 87vette81big » February 14th, 2015, 8:34 am

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.
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Re: Head and Cam Swap, 82 CFI

Postby Drawmain » February 14th, 2015, 7:30 pm

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.
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Re: Head and Cam Swap, 82 CFI

Postby 87vette81big » February 14th, 2015, 8:20 pm

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.
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Re: Head and Cam Swap, 82 CFI

Postby Drawmain » February 14th, 2015, 10:27 pm

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.
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Re: Head and Cam Swap, 82 CFI

Postby 87vette81big » February 15th, 2015, 12:47 pm

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:
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