Problem with FAST LSX rt intake
01-07-2011, 09:12 AM
#31
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It's the fast 102mm. Here is some more information, I just ordered the coolant crossover line that will work on the front part of the heads, the current number is GM part#12602540, the covers for the coolant crossover holes on the rear of the heads is GM part #12602540. This will eliminate the coolant crossover line from passing under the intake manifold. I'm having the valley cover cut down the thickness of the gasket and having the bolts countersunk so the head of the bolts will be below the top of the cover.
Last edited by ByuTrukr; 01-07-2011 at 09:57 AM. Reason: Want to add info
01-10-2011, 04:48 AM
#32
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Here are some pics I took. In the first two looking from front of engine, you can see how the manifold is touching the top of the bolts, the middle picture, you can see how it fits,on the fourth picture you can see the lip on the top of the head where the valve cover sits, I had to have that shaved for the manifold to fit under it
Last edited by ByuTrukr; 01-10-2011 at 04:55 AM. Reason: add explanation of pics
02-25-2011, 03:00 AM
#33
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Here's an update I countersunk the bolts the thickness of the gasket and the fit is good. I started the engine but so far it won't idle down, it's idling at 2200 rpm. I guess i need to do some tuning.
Last edited by ByuTrukr; 02-25-2011 at 03:13 AM. Reason: typos
02-25-2011, 03:14 AM
#34
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Found my problem with it not Idling down I forgot to connect the hose for the brake booster and was getting more air into the intake than normal with the throttle blade closed.
02-27-2011, 12:14 PM
#40
I have found they are more difficult to tune, but most of the time its because people try to keep adding air to the cracker and follower tables. A lot of times, the surging is from a condition where there is TOO much airflow. When the PCM or ECM has a target idle speed to hit and the airflow commanded is too high, it has to resort to pulling timing to try to curb the overspeed condition and it can cause a buck-nasty surging effect that usually goes away upon coming to a full stop (at the same time the throttle cracker airflow is disabled). Yes they can be more involved to tune, but a good tuner can tame it for sure.