454 crusaders rpm drop from neutral to fwd

[sbb2112]

Just wondering about a normal range the rpms will drop going into gear. I have carbed delco ignition with v drives on gas. 1992 vintage.

[km1125]

I don't remember exactly, but 50-75 RPM seems to ring a bell. But gearing and prop size probably impacts that a bit too.

[bud37]

A properly tuned healthy engine should maybe see maybe 50 rpm drop then recover as km said....imo

Set the engine to spec in gear if you are having issues.

[sbb2112]

I think everything is fine. Had someone help me out by tuning and idle adjustment. Idle seems too low and docking was tough in the wind. He said he put the timing at 8 btdc also. It idles at 600 and drops some when going into gear. Ordered a digital timing light with a tach and going to reset everything. It was fine before the adjustments.

[Viper]

Check your specs for that engine, 600 idle in neutral seems low to me. Check if the readings are to be taken in gear or not.

[km1125]

And 8 btdc seems too low too. I thought mine was 10 or 12.

[waybomb]

87 Crusader 464 350hp here. 8 degrees at 700 rpm

[km1125]

Well, y'all made me question my fading brain cells enough, so I went and looked it up!

I happen to have an 80-92 Crusader Service Manual and here's the spec sheets. Idle for all is 650-700 in gear. And 10 btdc. But it did remind me that if you have the E.S.T ignition make sure you turn the connector around when setting base timing.

454_timing1.jpg

454_timing2.jpg

454_timing3.jpg

454_timing4.jpg

[sbb2112]

Thanks all for the info. I am going to set to the specs shown for the delco ignition. Pretty sure raising the idle will make a big improvement.

[bud37]

QR_BBPOST Thanks all for the info. I am going to set to the specs shown for the delco ignition. Pretty sure raising the idle will make a big improvement.

I agree, a couple degrees is almost impossible to get right on an older engine anyway.

One other thing to be aware of can be the idle mixtures on the carbs, be sure they are not too lean. Many times folk will go for the best lean idle which I have found sometimes doesn't work well for me in any carbed boats we have had, slightly rich is a bit better at maintaining idle quality in gear/under some load.