Gen 3 Cam Swap

[Cheme1985]

Does anyone know of any good step by step resources to do a cam swap on a gen 3? I saw a thread from a user by the name of ChicagoPD or something like that where he put a Roe cam in and picked up over 50 RWHP. The swap included new springs, slow bleed lifters, and the new cam (obviously).

I am fairly mechanically inclined, but have never done anything this involved first hand. I love a good weekend project and think I would enjoy learning to do something like this.

Thanks in advance.

[345s-bspinnin]

Does anyone know of any good step by step resources to do a cam swap on a gen 3? I saw a thread from a user by the name of ChicagoPD or something like that where he put a Roe cam in and picked up over 50 RWHP. The swap included new springs, slow bleed lifters, and the new cam (obviously).

I am fairly mechanically inclined, but have never done anything this involved first hand. I love a good weekend project and think I would enjoy learning to do something like this.

Thanks in advance.

I swapped the cam on mine along with the heads. Its really no different than doing an LS engine or ford 5.0. I did mine with the short block still in the car and did not have pull radiator/condenser.

I did it while the heads were off which obviously means no pushrods/lifters on the way. The "trick" is that you drop remove the transmission support and tilt the tail down which in turn tilts the engine nose up. I never even pulled the out the drive shaft. I then lubed the cam properly and just patiently worked it in.

After that cam is installed, it absolutely critical that you properly measure for pushrod length. Your new "slow bleed lifters" will also likely have more limited travel than an OEM lifter. They sell height adjustable pushrods so that you can measure for the correct length. While you are at it, you can also get a degree wheel and ensure that the cam was ground properly.

I actually have both of these tools. I see that you are Houston based. I will see if I can dig them up so you can borrow them.

[99RT10]

The key is you want to do heads with the cam swap. Check PMs.

[pokeyl]

The heads will have to come off. I did mine. The only snag was the timing cover was stuck on my build. Other than that, just nuts and bolts.

https://driveviper.com/forums/threads/21273-Cam-Install

[Cheme1985]

Thanks! I might just take you up on that.

I swapped the cam on mine along with the heads. Its really no different than doing an LS engine or ford 5.0. I did mine with the short block still in the car and did not have pull radiator/condenser.

I did it while the heads were off which obviously means no pushrods/lifters on the way. The "trick" is that you drop remove the transmission support and tilt the tail down which in turn tilts the engine nose up. I never even pulled the out the drive shaft. I then lubed the cam properly and just patiently worked it in.

After that cam is installed, it absolutely critical that you properly measure for pushrod length. Your new "slow bleed lifters" will also likely have more limited travel than an OEM lifter. They sell height adjustable pushrods so that you can measure for the correct length. While you are at it, you can also get a degree wheel and ensure that the cam was ground properly.

I actually have both of these tools. I see that you are Houston based. I will see if I can dig them up so you can borrow them.

[Cheme1985]

Thanks for the info/thread. How do you ensure the cam timing is properly set to the crank on these motors when you do this? Also is the viper engine an interference engine? I would assume so since most modern engines are.

The heads will have to come off. I did mine. The only snag was the timing cover was stuck on my build. Other than that, just nuts and bolts.

https://driveviper.com/forums/threads/21273-Cam-Install

- - - Updated - - -

PM responded.

The key is you want to do heads with the cam swap. Check PMs.

[pokeyl]

I marked my balancer with open/close for intake/exhaust. Poor man degree wheel. I don't know if this is an interference engine.

Thanks for the info/thread. How do you ensure the cam timing is properly set to the crank on these motors when you do this? Also is the viper engine an interference engine? I would assume so since most modern engines are.



- - - Updated - - -

PM responded.

[Cheme1985]

Who do ya'll recommend for tuning in the houston area these days?

[Old School]

Also is the viper engine an interference engine? I would assume so since most modern engines are.

I would think a Viper is an interference engine. The only reason for designing an engine not to be, is when it's an overhead cam, with a timing belt that might break.

[Dan Cragin]

Its really best to pull the motor, then you can really clean everything up and get the cam properly centerlined.

There are several cams that work fine with the stock pistons. You can get good gains from a bigger intake valve, but you really need to replace the intake seats and guides.

Many tuners sell a package with the tune, so you dont have to start from scratch. Many cams reduce catalyst life and wont pass emissions, so consider that. You can make power and pass smog with the
right combination.

[Cheme1985]

I think I read that Roe will throw a canned tune in with the cam which I guess would be a good starting point a custom tune to be built.

I am not sure if I will try the swap in the car or pull the motor. I need to decide what I am going to do space wise in my garage I suppose.

Also good point about passing smog tests, but i live in Texas. It's not nearly as strict as California thankfully. They basically just plug into the OBD port and make sure no CELs are set off and you're good to go as far as I know.

Its really best to pull the motor, then you can really clean everything up and get the cam properly centerlined.

There are several cams that work fine with the stock pistons. You can get good gains from a bigger intake valve, but you really need to replace the intake seats and guides.

Many tuners sell a package with the tune, so you dont have to start from scratch. Many cams reduce catalyst life and wont pass emissions, so consider that. You can make power and pass smog with the
right combination.

[Cheme1985]

I've also read about the magnet trick to swap the cam without pulling the heads. Does anyone have any experience going that route vs pulling the heads?

[pokeyl]

The problem is the anti rotation bracket, it is almost Impossible to get the bolt out and back in. Trust me I tried. Pull the heads, put on the Gen 4 head gasket and get a small CR bump. The Roe can tune will be rich, get a dyno run and send them the data. The next tune will be spot on. Was for me!

I've also read about the magnet trick to swap the cam without pulling the heads. Does anyone have any experience going that route vs pulling the heads?

[Old School]

The problem is the anti rotation bracket

What is this?

[pokeyl]

What is this?

See Ref #18

https://parts.pomocochryslerjeepdodg...fts-and-valves

[Cheme1985]

One of the reasons I'm considering just doing the cam is if for $2,000 in parts it would put me at 550-580 RWHP, but it takes $5,000-$7,000 to get me to ~600 then I'm not sure that juice is worth the squeeze. That $/hp math isn't nearly as good as a simple cam and associated parts and everybody always says do the head while you're in there, but that's assuming you're paying shop labor rates. It's also a bit of morbid curiosity I suppose. How much of the NA build is just the cam giving me versus the head work. That's the engineer in me wanting to isolate variables. Plus my free time is free if I decied to open her back up and do the heads later. lol

I also have the ARH headers and corsa catback and a canned SCT 93 octane tune right now and it put down 472hp/523tq on the dyno around 6 months ago.

[pokeyl]

A good bowl port/valve job will pick up another 50-70 WHP. Cost here was $800.

One of the reasons I'm considering just doing the cam is if for $2,000 in parts it would put me at 550-580 RWHP, but it takes $5,000-$7,000 to get me to ~600 then I'm not sure that juice is worth the squeeze. That $/hp math isn't nearly as good as a simple cam and associated parts and everybody always says do the head while you're in there, but that's assuming you're paying shop labor rates. It's also a bit of morbid curiosity I suppose. How much of the NA build is just the cam giving me versus the head work. That's the engineer in me wanting to isolate variables. Plus my free time is free if I decied to open her back up and do the heads later. lol

I also have the ARH headers and corsa catback and a canned SCT 93 octane tune right now and it put down 472hp/523tq on the dyno around 6 months ago.

[345s-bspinnin]

Also good point about passing smog tests, but i live in Texas. It's not nearly as strict as California thankfully. They basically just plug into the OBD port and make sure no CELs are set off and you're good to go as far as I know.

I addition to CELs, you also have to pass by having all but 1 emissions readiness monitors ready.

My car has no CELs and passes all monitors even though I have high flow cats. Mine was remotely tuned by Todd at A&C.

[Cheme1985]

Super stupid question, but I’m assuming the viper cam and crank have dots to line up timing when doing a swap right? Point the crank up and the cam down to match and all is right with the world? And the new cam should be keyed? Cam degreeing aside.

[LATAMUD]

Super stupid question, but I’m assuming the viper cam and crank have dots to line up timing when doing a swap right? Point the crank up and the cam down to match and all is right with the world? And the new cam should be keyed? Cam degreeing aside.

Yes, the gears are marked with dots.

[Cheme1985]

Thanks!

[Old School]

See Ref #18

https://parts.pomocochryslerjeepdodg...fts-and-valves

I swapped my cam with these still installed, without removing the heads, using the magnet trick.

I also decided to pull the radiator for clearance instead of lowering the transmission tail-shaft. I didn't like the idea of tweaking the exhaust/headers that much.

[Cheme1985]

Thanks for the advice. At this point with the world falling apart I find myself being pulled in 2 different directions. One is to hoard my sheckels and not spend money on "non-essentials" because who knows what will happen to the economy. Option two is to buy car parts becasue if I can't go anywhere I need a new project to keep me sane right? lol

I'm assuming since you used the magnet trick to hold the lifters up you didn't change those while you were in there right?

What cam did you go with and what were your dyno numbers before and after?

I wish I hadn't been so eager to finish my motorcycle project this winter and had procrastinated with that a bit more...

I swapped my cam with these still installed, without removing the heads, using the magnet trick.

I also decided to pull the radiator for clearance instead of lowering the transmission tail-shaft. I didn't like the idea of tweaking the exhaust/headers that much.

[Dan Cragin]

What was the motorcycle project?

[Cheme1985]

For the longest time I've always the loved the (controversial, by Ducatisti standards) look of the Ducati 999 with its stacked headlights, but always wished it had a sigle sided swingarm like the 916 before it and the 1098 after. A low mileage last model year example popped up here in Houston local to me so I bought it last fall and decided to tackle it. First thing I did was get all the maintenance up to snuff by changing all the fluids, spark plugs, new larger diameter clutch slave cylinder, and new timing belts on it.

It was a biposto model and I like the look of a mono plus I never take anyone on the back of my sportbikes so picked up the mono subframe and rear fairing and swapped that out.

They are also notoriously hard to start when cold in the best of times so I also fabbed some new larger diameter cable leads for the starter, battery, and grounds as well as put in a lithium ion battery to solve that issue.

I was able to get the swingarm off of my 1198 to fit to the 999 frame so I bought a used swingarm, wheel, shock, link, and rocker off ebay and decided to tackle it. The crux being the stock routing of the vertical cylinder exhaust interferes with the 1198 shock setup so I fabbed a custom exhaust in my garage to make it work. I am very pleased with how it turned out, but now I'm bored again...