note that the cam is a hydraulic roller design so if your block is newer, it should be equipped to install this type of camshaft. I put this cam in my engine rebuild/re-power and I can say that I am very happy with the performance of our boat.

Here are some numbers distilled from the above that you can plug into you cam calculator to get close to the above actual opening and closing points. Intake Close 60-abdc 53-abdc 24-abdc 20-bbdcĮxhaust Open 63-bbdc 60-bbdc 35-bbdc 8-abdcĮxhaust Close 28-atdc 23-atdc 10-btdc 54-btdc Intake Open 20-btdc 17-btdc 7.5-atdc 50-atdc I did not take duration at lash point as that is pretty meaningless but GM says it is 288/308 - lift measured right on spec with. Note that lobes appear to be asymetrical on opening and closing sides. Here is some more cam info to help if you are planing to degree the cam- I cant vouch for the accuracy of the specs as they were pulled from a chevelle website: The gm performance ht383E is rated at 323 horse and. The 350 Marine cam would be a good one if used with good flowing heads like the Vortecs they were designed for.Įven though they look pretty mild they actually make good power. And i put that same cam in a vortec 350 but I have not ran either yet. These are really a very good cam choice and GM used them in the 350 Ramjet and HT383 crate motors. If it is from a Marine 5.7L Vortec the most common cam has the following specs: These cams as new takeouts can often be found on eBay for less than $100.Here is some info I found on a camshaft with similar specs you are looking for: I've used this cam with the 1.5 rockers, and it runs really well IMO. With the Vortec heads youll be fine at 10:1, imo. That is what you need for a great driving DD that has tons of torque, off-idle throttle response and good fuel mileage. The cam you selected is the RamJet 350 cam, and its a torque monster. The duration is in the 190* range on intake and about 210* on the exhaust. A big camshaft in a DD is a pain in the ass. 1.5 rockers were used and in the Ram Jet 350 1.6 rockers were used. If you want to upgrade your cam with out all the work and expense of upgrading the springs, take a look at the cam that GM used in the HT383 and the Ram Jet 350. If you don't want to pull the heads, you can change over to the Comp beehive springs and retainers, which will give you more valve lift capability. The stock Vortec springs and retainer to guide clearance is only good to a max of.

common in the Vortec truck motor applications. For one your valve springs will bind, and the retainers will hit the valve guides and seals. designed to pull lifters ( the tool old lifters with a new cam or vice- features internal jaws that. That's too much cam for a basically stock 元1 engine.

Vortec 350 cam specs