12cm2 Installed - Smiles for Keeno

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Hellow First Gener's!

Over the weekend I finally got the 12cm2 turbo housing installed on my truck that had been sitting on the workbench for a few weeks. I removed the Banks supplied 14cm2 and replaced it with a used 12cm2. The differences weren't as great as I thought but you have to remember the change was from a 14 to 12 and not stepping down from a 16.

The greatest advantage to the 12cm2 comes in the form of low end produced boost. The boost needle runs up to 22 PSI in an instant in 2nd and pushes all the way to 28-30 PSI in the other gears with instant throttle response. I have found that I have to control the throttle more accurately than before to eliminate any driveline slop & lash.

The 14cm2 was running 28 PSI @ 1100 degrees F with the wastegate disabled. The truck would turn 24 PSI @ the same 1100 degrees with the Banks set wastegate operating as designed. With the 12cm2 I'm seeing 30 PSI @ 1150 degrees running the wastegate disabled 5th/flat/unloaded. I've only noticed a slight increase in EGT of 50 degrees or so.

Beside the increased torque across the RPM band and instant throttle response in 5th, I'm also seeing less smoke in the exhaust. Maybe I'll give the max fuel screw another 1/4 turn to match the increased boost/oxygen at lower RPM. I think the 12cm2 has found a permanent home on my First Gen!

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1992 W250 5spd. 3. 54 gears, LSD, JRE enhanced VE Injector Pump, BD High Output Injectors, Banks "Stinger Plus" consisting of a 14cm2 wastegated housing, 3 1/2" JRE modified exhaust/muffler, pyro/boost gages, K&N, Skyjacker 2 1/2" front suspension lift to clear 305/70R/16 Goodyear MT's, Mag-Hytec, Amsoil

 

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Good job KEENO!

Time for a 40 psi boost gauge. #ad


Turn that screw to get your smoke back and then hang on!

Isn't it unbelievable how much "latent power" there is in that little VE pump?




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'93 W350 Club Cab, Bright White, 5 sp. , 130K, Factory Options: Bucket seats replaced with factory split bench, LE, 4. 10, Limited Slip, 7600 lb. rear springs, tachometer, front stabilizer bar. Mods: Banks stinger plus, Linex bedliner, 25,000 lb gooseneck ball, 10,000 lb receiver, Tekonsha
brake controller, POWER WAGON injectors-WAY faster than stock!.

 

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Outstanding. Good to see you're pleased with the result.
(Try the AFC and the diaphragm rotating the fuel rate pin for lower RPM fueling rate increase. ) Hehe.
I know you're watchin' the EGT.
Hey now... . watcha'all doing with that ol' 14cm?



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'98 2500, Cummins 12v, 5spd, 4wd, 3. 55, 300 injectors, JRE III power kit, 4" turbo to tail system, boost/pyro, did I mention 12 valves? GOT DIESEL?

 

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Hey, where can I get one of them there 12cm turbos 'ol buddies?

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Mine: '93 250 LE 4x4 5spd 4:10 Pwr win/loc/mir,cruise,strait piped,fuel pump cranked,diamond plate tool box, CB, 16x10" AR rims, 285/75/16 Bf goodrich, US Gear E-Brake, K&N. "wirenut_21529" on Yahoo Messenger
Moms:'96 Ford B-Series school bus (5. 9 Cummins!)I'm gonna Bomb it!
Dads:'94 GMC 2500 6. 5L Turbo

 

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Keeno, sounds like your result parrallel mine. I knew you would like the feel. I did indeed go to the 50 psi boost guage. I'm leavin mine alone now. . it just runs too good to mess with any more... .

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93 ClubCab LE 250, 4X4,K&N,
4" Chrome tube out the top,BFG 315/75R 16's
106K, 10K-GVW Springs w/GN hitch. 12cm/2 tbh

 

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Hey Gang!

Thanks for all of the encouraging words! I've received a few emails inquiring as where to find used 12cm2 housings. I had many email discussions with Joe Donnelly in my quest for a used 12cm2. Joe has many used and new 12cm2 sitting on his shelf ready for consumption if interested. If so, drop him an email using his email icon. His pricing is very reasonable and his advice is usually free!

Old School! I have made the offer to Xanderbilt to install my old 14cm2 on your former Powerhouse. It's funny, I can see you cringing all the way here in Tennessee! Regardless, I don't think she's completely interested (good girl, Huh!). I originally planned on keeping it in case I planned to go back, but after a few days of driving the 12 I doubt this will happen.

If you really want it, keep working on me and I might be convinced to send it north for a reasonable price and some Moog tie rod ends! I had to use the exhaust flange/wastegate cover on my 12 so you would have to pick up a cover and a few bolts. It's only 8 months old and has the Banks "Big Head" actuator assy. If you ask Banks these 14's are worth there weight in gold, I might be able to do better for a friend!

Keeno

 

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Keeno; what hose did you use to connect the 12cm turbo to the air cleaner?

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http://coffeewithJesus. homestead.com/web1.html 89 1-ton, K&N, cleaned up exhaust, Dynomax straight-thru, rebuilt pump, intercooler, louvered fenders, 93 aftermarket smoothe grille; 78 35'Avion. Jesus saves!

 

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Hey Jsimpson!

The intake hose that I'm using is the OEM part that came with my '92 truck. It has now fit my 21cm2 housing, along with the 14cm & now the 12cm. Were the older style intake hoses different?

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1992 W250 5spd. 3. 54 gears, LSD, JRE enhanced VE Injector Pump, BD High Output Injectors, Banks "Stinger Plus" consisting of a replaced 12cm2 wastegated housing, 3 1/2" JRE modified exhaust/muffler, pyro/boost gages, K&N, Skyjacker 2 1/2" front suspension lift to clear 305/70R/16 Goodyear MT's, Mag-Hytec, Amsoil, Rhino liner, Fully Chrominated Aluminum Aftermarket Accessory T-handle Shift Knob

 

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Hello jsimpson and KEENO: Possibly a little description of the housings would help. The housings KEENO is referring to are the hot end ones, which are seperated from the compressor end housing, swapped, then assembled to the original compressor housing. the comp. end remains as is, in the original position. All the original connections (intake hose, lube lines) are refit as original.
Mr. KEENO... I just noticed your post at 4:30 P. M..... Hehe.
Have fun.

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'98 Cummins 12v 4WD 5SPD Big Medicine. Got Diesel.

 

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Old School. am I better off using the whole 12cm unit, or swapping the hot end and using my old intake end?

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http://coffeewithJesus. homestead.com/web1.html 89 1-ton, K&N, cleaned up exhaust, Dynomax straight-thru, rebuilt pump, intercooler, louvered fenders, 93 aftermarket smoothe grille; 78 35'Avion. Jesus saves!

 

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If your compressor end is in good condition, I'd change out the hot end. That's the quick answer, but... ... .....
A couple of items to consider:
The 12cm turbo wants to have a wastegate. Be aware of the added space required between the hot end exhaust outlet and the exhaust pipe clamp up end.
Are you running an intercooler? With your fueling "up", and a smaller housing, you would want to really consider one.
I read your signature, and didn't see a boost or pyro gage. You want these if you don't already have them. And pre-turbo the pyro gage.
Hope this helps the thought process.


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'98 Cummins 12v 4WD 5SPD Big Medicine. Got Diesel.

 

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Thanks Old School; that helps the process a lot!

 

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Just a few questions. How much room does a wastegate add to the equation? Does this require a different down pipe? Do they make a 14 cm2 without a wastegate?

Matt

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90 W250, 5-speed, 3. 54 gears, 16 cm2 housing, tach, pyro, and boost gauges, K&N air filter.

 

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Hey if anyone else needs a 14 I have one for sale all set up with the Banks Big Head on it. To much fuel had to go to the 16.

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1996 4x4 3500 4. 10 5spd, Diesel Dynamics stage 2 injectors, #5 TST plate, Govoner spring kit, 16cm2 housing with 4" exhaust, Cummins exhaust brake, US Gear overdrive, Grover air horns, Mag-Hytec cover, and more.

 

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Hey Gang!

Sorry Jsimpson, I wasn't understanding the depth of your question! Thanks for clearing this up for us Old School, I now see what was so confusing. I should of have been more detailed in my descriptions and mentioned that I was only working on the exhaust side of the turbo not the 'compressor' side.

Which brings me to a question. My '92 has a Holset "HIC" type compressor and not the "HX35" that I have read so much about. What are the design differences?

Lt, The difference in the wastegate exhaust housings is 1. 25" per J. Donnelly. I have also heard 1. 5" used a rough estimate and "YES" the exhaust system does have to be moved rearward this amount but uses the same flange.

Question: I know it's difficult to weld 'cast iron' but I'm wondering if it would be possible to weld or permanently 'fill' in the wastegate hole on a 12cm2 and remove the linkage assy?

Keeno