11.5.1 CR + stock 346 =??
09-18-2011, 09:34 PM
#21
Damian's right that the 3.898" bore cannot adecuetly unshroud the 2.05 valve
and this as well as the milling adds to your PTV issues. He also wants you to
properly match the springs to the cam as this is a VERY important part to the
sucess of an LS engine. I'm just guessing that the 2 sets of springs you have
are either too light or too aggressive for what your cam needs. The PSI ML
springs are real nice for under $200. No-one wants you to later have a WTF
thread.
and this as well as the milling adds to your PTV issues. He also wants you to
properly match the springs to the cam as this is a VERY important part to the
sucess of an LS engine. I'm just guessing that the 2 sets of springs you have
are either too light or too aggressive for what your cam needs. The PSI ML
springs are real nice for under $200. No-one wants you to later have a WTF
thread.
09-19-2011, 06:12 AM
#23
TECH Senior Member
If installed at correct height, PAC 1218 will control those valves and that cam.
That cam is XER and .588 lift.
Specs on 1218 are:
Part # O.D. I.D. Seat Load Open Load Coil Bind Rate (Lbs/In)
1218 1.290 .885 130@1.800 318@1.200 1.140 313
Also it is not necessary to put 2.05 valves for the return it gives, there is no huge issues with them on a 346cid.
Important:
1- Measure PTV clearance
2- Measure for p-rod length
That cam is XER and .588 lift.
Specs on 1218 are:
Part # O.D. I.D. Seat Load Open Load Coil Bind Rate (Lbs/In)
1218 1.290 .885 130@1.800 318@1.200 1.140 313
Also it is not necessary to put 2.05 valves for the return it gives, there is no huge issues with them on a 346cid.
Important:
1- Measure PTV clearance
2- Measure for p-rod length
09-19-2011, 07:10 AM
#24
If installed at correct height, PAC 1218 will control those valves and that cam.
That cam is XER and .588 lift.
Specs on 1218 are:
Part # O.D. I.D. Seat Load Open Load Coil Bind Rate (Lbs/In)
1218 1.290 .885 130@1.800 318@1.200 1.140 313
Also it is not necessary to put 2.05 valves for the return it gives, there is no huge issues with them on a 346cid.
Important:
1- Measure PTV clearance
2- Measure for p-rod length
That cam is XER and .588 lift.
Specs on 1218 are:
Part # O.D. I.D. Seat Load Open Load Coil Bind Rate (Lbs/In)
1218 1.290 .885 130@1.800 318@1.200 1.140 313
Also it is not necessary to put 2.05 valves for the return it gives, there is no huge issues with them on a 346cid.
Important:
1- Measure PTV clearance
2- Measure for p-rod length
09-20-2011, 10:46 PM
#25
09-21-2011, 12:35 AM
#27
Some interresting stuff in Damians post but I have point out something about the chamber size of 5.3 heads.Damian is forgetting that the chambers in ported 5.3 heads are not the stock 61 cc chambers.When the big intake vavles are put in the chambers are opened up around them.I think a lot of these heads are 63 cc unmilled-my ETP 5.3 heads are 64 cc unmilled.That is why .030 off would be 58cc.
I have a set of TEA ported 5.3 heads. They have been shaved .030 and they are at 59cc so I would say that is accurate.
When I bought my heads they had the 977 springs on them and after reading about them I pitched them and went with 921's which is probably a little overkill for what I'm doing but they are really nice springs.
If you change to a single spring you will have to change seat locators because of the difference in the outer diameter.
09-21-2011, 08:02 AM
#28
