Tech Tips

        C1TE/C0AE Cylinder Head Mods
          (January 2011: How to get performance without ECZ-G Heads) 

Anyone who has had a car, pickup or Hot Rod with a Y-Block in it knows that you just have to have a set of ECZ-G heads if you want to make any power, NOT TRUE! Although if you are making a race engine the "G" heads or 113 castings are preferred, if you are just running on the street you can make decent power with a set of old truck heads. That's right! all those C1TE, C1AE and C0AE castings that everyone just passes over are very good heads with a little work.

To start with they have 76, 72 and 75cc chambers respectively, the "G" heads have 69cc chambers but with a little milling you can get the volume down and all these heads are "Posted". Bonus! Rule of thumb is .005" off the surface 1cc reduction so take .020" off and that's 4cc's.

Now for the fun part. I've been using 1.85" and 1.6" SI valves meant for a sbc +.200" length.

Stock chamber


I cut the exhaust first since the stock valves are slightly smaller than the 1.6" SI valves. The intakes however are.200" to gain.

After cutting the seat


The next step is to cut the excess meat in the bowl left after cutting the bigger seat.




Now all that's left is to grind the rough edges out and make a smooth radius from the port to the chamber. You can polish this as much as you like but the biggest gain is from cleaning it out not making it shiny.


I use stainless swirl polished valves and you do need to cut the giudes down about 1/8" so the retainers wont hit with .500" lift.




You can do this on other heads not just Y-blocks just make sure you have enough material before you cut, you don't want to hit water.

These heads are going on a 292 that will power our LSR Unibody for some testing, although this engine is not likely to break any records (158 mph is the D/PP class record at Elmo) I do hope to better 130. I'll keep you posted.


Update 2012: These heads running on a fairly stock 292 in my Unibody pickup at Bonneville in 2011 did three back to back runs at 120 mph. With a change of heads on the salt to ECZ-G heads that were formerly on Charlie Burns "Yellow Brick" 258ci Y-Block the Uni improved it's speed to 127mph. this will give a good comparison on performance. Keep in mind that the "G" heads were "worked over" extensively, I believe (refer to dyno chart below) that the reworked C1TE heads perform on the same level, or better, than stock "G" heads.


http://www.jalopyjournal.com/forum/s...d.php?t=531700

 

Dyno cylinder head test by Ted Eaton

 

 

Here are the ‘very summarized’ results of how sixteen different pairs of heads recently performed on the 312 dyno mule. A pair of the ECZ-C’s and C1TE-D’s was a before and after milling comparison which jumps the number of published tests to eighteen. The same carburetor, intake, headers, timing, and valve lash was used in all these tests. The camshaft is a Crower Monarch with 0.450” lift, 238°@0.050”, ground on 110° lobe centers, and installed 2° advanced or 108° intake lobe centerline. The intake manifold is an unported Mummert dual plane paired up with a 750cfm vacuum secondary Holley sitting atop a 2” oval opening carb spacer. 1.6:1 roller rockers are being used for all tests. Total ignition timing is 38° BTDC. For these particular test results, the headers are used with mufflers which helps to keep this particular information set comparable. The degree or amount of porting when performed on the heads is not listed on this particular chart.

 

Cylinder Head

Peak HP

Peak Torque

Comp Ratio

Ported

Mummert Aluminum

377

368

9.8:1

Yes

Mummert Aluminum

354

356

9.8:1

No

113

333

350

9.2:1

Yes

*G

328

350

9.4:1

Yes

G

324

349

10.6:1

Yes

G

304

337

9.6:1

Yes

G

302

337

9.2:1

Yes

G - stock

290

344

9.2:1

No

471

296

332

8.3:1

Yes

ECZ-C – stock

288

336

9.0:1

No

ECZ-C – stock

280

335

8.6:1

No

ECZ-C – stock

273

330

8.1:1

No

*ECZ-C after milling

295

339

9.0:1

Yes

*ECZ-C before milling

290

334

8.4:1

Yes

*C1TE-D after milling

297

337

9.0:1

Yes

*C1TE-D before milling

295

335

8.4:1

Yes

COAE-A - stock

283

332

8.7:1

No

COAE-A w/larger valves

273

328

8.9:1

No

A special thanks goes out to those of you that donated heads, shipping, and/or funds to make all this happen. For those of you that sent funds without any name(s) on the envelopes, an extra thanks also. This testing has generated a plethora of information which is being put together for a series of articles for the Y-Block Magazine.

Lorena, Texas (South of Waco)

 

*Heads by Tim McMaster

 


 
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