# Why are intake camshaft sprockets bigger than exhaust camshaft sprockets?

**URL:** <https://community.cartalk.com/t/why-are-intake-camshaft-sprockets-bigger-than-exhaust-camshaft-sprockets/168261>\
**Category:** General Discussion\
**Created:** [August 4, 2020, 1:45pm UTC](https://community.cartalk.com/t/why-are-intake-camshaft-sprockets-bigger-than-exhaust-camshaft-sprockets/168261 "2020-08-04T13:45:37Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![bugattiveyron534\_169674](https://avatars.discourse-cdn.com/v4/letter/b/b2d939/32.png) [@bugattiveyron534\_169674](https://community.cartalk.com/u/bugattiveyron534_169674)\
**Post date:** [August 4, 2020, 1:45pm UTC](https://community.cartalk.com/t/why-are-intake-camshaft-sprockets-bigger-than-exhaust-camshaft-sprockets/168261/1 "2020-08-04T13:45:37Z")

</div>

hello I want to know why intake camshaft sprockets on higher performance engines are larger than exhaust camshaft sprockets. I know that on smaller timing belt engines the exhaust camshaft and intake camshaft ends are the same size, but why is that different with timing chain engines? I would think that having a larger intake camshaft gear reduction would mess up timing.

---

<div class="post-metadata">

**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\
**Post date:** [August 4, 2020, 1:47pm UTC](https://community.cartalk.com/t/why-are-intake-camshaft-sprockets-bigger-than-exhaust-camshaft-sprockets/168261/2 "2020-08-04T13:47:24Z")

</div>

I haven’t seen this. Care to post a link to a picture? They both have to turn at the same rpm.

---

<div class="post-metadata">

**Author:** ![bugattiveyron534\_169674](https://avatars.discourse-cdn.com/v4/letter/b/b2d939/32.png) [@bugattiveyron534\_169674](https://community.cartalk.com/u/bugattiveyron534_169674)\
**Post date:** [August 4, 2020, 1:50pm UTC](https://community.cartalk.com/t/why-are-intake-camshaft-sprockets-bigger-than-exhaust-camshaft-sprockets/168261/3 "2020-08-04T13:50:20Z")

</div>

Like this image here from a VQ37VHR ![image](https://global.discourse-cdn.com/cartalk/original/3X/0/0/009e77a80d0649361f5bd1aa37c74d998304a750.jpeg)

---

<div class="post-metadata">

**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\
**Post date:** [August 4, 2020, 1:52pm UTC](https://community.cartalk.com/t/why-are-intake-camshaft-sprockets-bigger-than-exhaust-camshaft-sprockets/168261/4 "2020-08-04T13:52:35Z")

</div>

OK, the big sprocket is the one driven by the crankshaft. What you can’t see is the small sprocket behind the big one that connects the second chain drive to the exhaust cam. Both of those sprockets are the same size. If you look at any engine with all cams driven by a single chain all the cam sprockets will be the same size.

---

<div class="post-metadata">

**Author:** ![bugattiveyron534\_169674](https://avatars.discourse-cdn.com/v4/letter/b/b2d939/32.png) [@bugattiveyron534\_169674](https://community.cartalk.com/u/bugattiveyron534_169674)\
**Post date:** [August 4, 2020, 1:54pm UTC](https://community.cartalk.com/t/why-are-intake-camshaft-sprockets-bigger-than-exhaust-camshaft-sprockets/168261/5 "2020-08-04T13:54:11Z")

</div>

OOOOH. Ok I think I get your point now. I was gonna post another picture of another engine like that, but now since I have my answer, nevermind. Thanks for the help!