First things first...This is in a Chevy Caprice with the LT1, I am posting this here as well as the impala forum, but here has more readers and more input.

Ok on to the good stuff., well a guy locally was selling a big cam that he was planning for his fbody and he went a different route. I picked up the cam cheap. It is a comp cams XE 230/236 .510/.520 (with 1.5 rockers)

My waterpump started leaking so I bought A meziere HD, and took things apart. After 3 hours of fighting with my car the WP came off. After that hassle I decided I don't want to do it again so off came the Optispark.

Then the idea hit me. After I took the opti off I saw the end of the camshaft there staring at me. And here I have this big ole cam sitting there ready for my engine build. I am saving up money for ported heads upgraded fuel system and the like.

But then it hit me. Why not put the cam in now and do the heads and such later?


Question 1: Can you reasonably do a cam swap without removing the heads? Without pulling the engine?

Question 2: What ABSOLUTELY MUST be changed for a camswap to be safe on a 140K mile engine? (ie timing chain, lifters, main bearings, yadda yadda yadda)

Question 3: Is .510/.520 lift with the stock 1.5 stamped steel rockers too much? (I have a set of combination motorsports valvesprings I would most likely be putting on)


I am putting off porting the heads because I would want to switch to Aluminum heads due to lighter weight and easier to work on, and I would want a stage 2 or so port job, so we are talking 600-1000 for a good set of heads.

If I must take the heads off to do the cam swap I will probably clean up the ports myself and have the studs pinned in or maybe even go to screw in studs, but that starts to send the budget for the swap too high for now.


I am not a patient person and the idea of this cam sounds real fun, but I would hate to swap it in then have my engine grenade on me. I will do it if I "may not see full potential" or have minor driveability issues. But safety and reliability are important.

Considering I have the waterpump and opti, my budget from here on would be 200-400 and I am set on buying a Cloyes double roller chain since I have the electric WP, so say 100-300 left in the budget for gaskets and related parts. This leads to the big question:

Is it do-able?

Any help is greatly appreciated.


P.S. Here are my current mods:

All Free Mods, 160 T-Stat, PCMforless tuning, 3.73's, Posi, Stage 3 4L60E w/ 2400 Stall (stalls closer to 3000 though), Hooker Shorties , Custom 2.5" Exhaust no cats, Cutouts, X-Pipe, Flowmasters, and Dual 2.5" Tips, Eibach Springs, Upgraded Swaybars and Bilstein Shocks, BMR Control arms, and bunches of other little stuff.

 

as for costs im not too sure on, but you will need to remove the intake as well, then the lifters before the cam comes out. i recomend you do the timing chain and lifters at this point as well. a buddy ran that can with stock rockers for a while but has since moved up to the 1.6rr. i highly suggest you change the springs and lifters as well. you can do the cam swap without removing the heads, you can leave the motor in there as well, but you may have to drop the rad out and move the ac condensor. as for gaskets youll need the intake gaskets timing cover gaskets possibly oil pan gasket if you dont remove the timing cover properly. and you will need retuning as well.

 

Ok, I can get tuning no problem. I was counting on that. I have a data cable and lifetime retunes from PCMforless.


Lifters are not too expensive so I can probably swing those too. Now all I have to do is find the cash to buy the parts in the next week or two.

 

As with any car, performance mods aren't meant for reliability. With 140K on the clock you have a 50/50 chance the bearings will last. Its a wierd thing that some cars with 40K lose the bearings quick after cam install. I personally think bearing failure is from overreving, dirty install, or oil problems. So as long as your clean with the install and keep the stockish rev limiter you should be fine. Every motor I have torn down with bearing failure is usually an oiling related problem. As long as you feel confident in the bearing's condition then I would go for it. Replacing the waterpump and optispark is a good decision too. As far as the valve train is concerned I would replace pushrods (less than $100), lifters, springs, and rockers. You could keep the stock stamped rockers but I have seen a few cammed LT1's break rocker studs and pushrods with these. Other than that, hell just go for it you will be much happier. If the motor seems healthy i say do it, you only live once! Good luck...

 

Thats the first time I have heard anyone suggest changing the pushrods. The general concensus on the Impala SS forum is that since my 95 has the hardened pushrods they will be fine.

My motor seems perfectly healthy right now. I burn no oil, it gets reasonable mileage for my mods/driving style.

A couple weeks ago the track was next to empty and I got 24 almost back to back runs down the strip and the only downside was my waterpump started leaking.

I am always very thorough with maintenance and upkeep.

I have yet to hear anyone say not to do it.


However people on the impala forum are really afraid of big cams. I didn't even post that I have the XE 230/236, just posted the lift numbers, but some people are freaking out (they may have researched my previous posts and found what cam I have) saying that my power peak will be closer to 7K and will need "AT LEAST a 3600 stall". I am thinking this cam should fit well with the mods I have already.

 

I say go for it, emoving the intake is a sinch, and its not that much more money. This cam is big, actually the largest I would go with on a street engine, but it should work fine for you. I almost went with thsi one, but am opting for forced induction-if I don't change my mind again. Anyway your right about the pushrods, they should be hardened, roll them on a flat piece of glass to see if there are any bent ones, if not reuse them. I would also reuse the stock lifters if you can't afford them until you pull the heads off. It would be better with new ones, but if they go they're easy to change out. your stall convertor should work fine, obviously a higher stall will net better times, but if its a daily driver than you really don't want to go past 3200-personally I stay around 28-3000. changing the cam is easy, remove radiator and condensor and it slides out with enough room. Some people bend the condensor lines out of the way instead of sidconecting it, so as not to lose their ac freon, but if the line cracks or breaks, you'll end up spending to more money. A kit with ac freon cans is around 30 bucks, if you break the line from bending it out of the way instead of disconnecting, add at least another 30 bucks. The valve springs are the biggest pain, if you have an air compressor you can hold the valves up while you change the springs, otherwise you'll need to make sure each cylinder is at top dead center. I prefere the air method, plus you can easily rent one. Be careful when removing the timing chain cover, as it could tear the bottom oil pan gasket, I had to slowly pull while using my fingers to gently pry them apart. Also install a new opti seal in the timing cover after the cover is installed, because its impsosible to put the cover on without messing it up, and when it leaks believe me, it pours out. As stated before dirt will destroy the bearings and such, keep everything as clean as possible. I would leave the intake on until your ready to put the new cam in, this way no dirt can enter while its off. Make sure the engine is at #1 or #6 top dead center before pulling the chain and cam, this way everything is aligned correctly. also I wouldn't replace the opti unless its bad, why spend more money if you don't have to, mine has had way to much coolant on it, and it still runs great. I had a leaky waterpump on it with a nice stream pouring on the opti for 10,000 miles plus three more waterpump changes and it still goes. Not saying you'd have such luck, but only that it might not be time for it yet

 

The intake will have to come off so thats $24 bucks for those gaskets. Then the rockers and pushrods have to come out ...then the lifters. If your sticking with the 1.5 rr you should at least get some lt4 springs IMO...you can get those from Pace for $40 for the set and your stock retainers and keepers will work with them.
If your pushrods are hardened they should be fine. Of coarse your most likely going to have to remove the radiator and ac core to get the cam out. So , heck yeah, do the cam now then do your heads later(port ,polish,1.6rr and new springs)

 

Ok, I have tried and tried but never heard someone tell me not to do it. So it is going in.


The only question I have left is: Is it neccesary to replace the lifters? If I don't what harm will it have. If I do what lifters are a good value.



Right now I am going to do the minimum to get it done (some basic cheap 1.5 rr's, and so on) And I plan on replacing everything in the top end with the real good stuff when I do the heads in a year or so.

Thanks again for all the help.

 

Stock lifters will be fine as well as the stock 1.5 rockers....if your gonna buy new rockers by all means go ahead and get the 1.6rr and a spring set that will handle the additional lift. I would just stick with what you have till your ready to do the heads....just dont spin it up over 6000rpms and you should be ok.

 

ya what this guy said, your stock lifters and rocker arms will work fine, until you can afford new ones. People are just saying replace them since you have some miles on your car, and your in there, but if you don't have the money, just wait till they go. IF you plan on reving past 6000 get a better timing set, I didn't and wished I had the money to do so, so I have to keep them low. I would suggest getting some springs because you could cause some serious damage without new ones, like bent pushrods, bent valves etc.

 

what you need to get for longeity (I am considering the same thing as you, so I've already done the research):

timing chain (go with a cloyes double roller since you have the electric H2O pump)

valve springs/locks/retainers, I recommend the valve spring kit from www.cmotorsports.com (LT4 valve springs won't work it you put 1.6 rockers on later) its like $70

gaskets including water pump, front cover, etc. Thunder racing sells a cam swap gasket kit for $89

you can use the stock pushrods and lifters but if you have some extra money, new lifters wouldn't be a bad thing. Be prepared to pull the entire front of the motor off including the radiator, moving the condensor, etc.

 

Was planning on the Cloyes Double Roller

Already Have the Combination Motorsports Springs

Going to order all the gaskets from Dal since he seems to be very reasonably priced.

The only reason I am going to go with 1.5's instead of 1.6's is that the iron heads have pressed in rocker arm studs instead of Screw in. Also the lift with 1.6's would be .544/.555 which would probably cause clearance issues with the valve guides.


I talked to combination motorsports on the phone and they said that 1.6's would be pushing it even with the "blue line" valve guides.

The rumors of people snapping studs with stock stamped rockers have me worried, and I found a set of 1.5 rr's for 125 near me so I can squeeze that into the budget.