Engine braking

[Rich]

02 Trans Am with A4 and GM Hot Cam. Tune is good and car is running great, just one problem. When driving down a steep hill or down a mountain I wish I had more help from the engine slowing down, I guess you call it engine braking. What table should I look at? Is it an IAC adjustment or throttle follower? Thank you for any help.

[69camaro5speed]

under idle it's called throttle cracker airflow in gear.It the bigest one but there are others that afect it also.I have spent hours lurning how to make big cam stuff idle good under differant loads. Data logs can be your friends here look at what makes it happy and what doesn't. That gives you a idea what needs done. Then the fun part understanding tables to know how to get there.

[Redline Motorsports]

I agree that you need to pull some air out so the rpms don't hang. This will greatly improve engine braking effect.

Sometimes its a balance between desired airflow and throttle cracker and follower.

Howard

[WeathermanShawn]

If you alter DFCO MAP Enable (B3320) by increasing the stock MAP enable (18) to 25-30..that will slow you down dramatically.
Also DFCO Spark Timing (B3336). Drop that to 0 degrees..

I've used those tricks down very steep mountain descents..never had to use brakes or downshift (M6). The TC will also work..but if you are only interested in engine breaking while descending..DFCO will work.

[Rich]

Thank you everyone, I will use your suggestions.