I plan on doing heads and cam swap in stages. First stage would be to order some P&P heads with aftermarket springs. I will install the heads , springs, and lifters at once. then later after I get more $ and get my cam speced i will do a cam swap. since i already swapped my heads and springs there is no need to take the heads off - just need to replace the pushrods.

is there any issue with running high lift springs on the stock cam that will barely be lifting them? like a .450 lift cam on a ~.625 dual spring or something like that?

thanks
_Zblee

 

<p>The issue is possibly with the stock push rods not being strong enough. &nbsp;They could bend with the force of the stiffer springs.</p>

 

Not saying its good but ive ran dual .650 lift springs on an ls9 cam stock pushrods with no issues.

 

I meant to add that in the original post. I will be upgrading the pushrods as well with the headswap. The heads will most likely be milled and new pushrods will be needed and will use good ones. They will need to be swapped again once the cam goes in .

so that seems to be the only issue? which in this case is not existent since i plan on changing out the pushrods as well

 

It should not hurt anything but I would shim them a little to put a little more pressure on the seat. If you need any help with this give us a call.
Thank you,
Kyle
972-853-2450
Thompson Motorsports

 

I think it would be worth waiting to spend the $350 to get the cam done at the same time as the heads. Not to mention the cost for a retune.

 

Tuning is done by myself and no extra cost. not sure where this $350 amount is coming from?

Can you explain Why it would be worth it? I am installing these on weekends so it would be easier for me to install just the heads first and do the cam swap on a different weekend. Cam swap and head swap are two different installs with the only thing overlapping being the pushrod change. otherwise, the head install doesnt require the cam or from cover to come off and the cam doesnt require the heads to come off...

 

Go in and do it all at once, not like youd be that far away once you pull heads anyway, then you only have to do pushrods once!!! Not to mention coolant, oil change etc that really need to be doneafter any internal wotk done!!!

The previous mention of $350 was for the cam... Most cams run $350-400...

 

for the cam swap I wouldn't be any closer if i had the heads off, head removal is not part of a cam swap...

I do not mind doing a second oil change or coolant drain. I just really want to split the installs out as to not do them both at the same time, IF and only IF there is no issue running the large springs on the stock cam.

To me it will be easier to do a head swap, get it all working and trouble shoot any issues. then after its running good, and I have more time, i can go in and swap the cam. something is probably going to go wrong with either install so it would be much easier to trouble shoot the issue if its limited to only a head swap, or only a cam swap (less variables).

so far I have not found any evidence that doing a headswap with larger springs and using low lift stock cam will be an issue. I am going keep asking/researching a bit further before I actually do it.

thanks for the input so far
keep them coming , i still have time as I am still trying to figure out which head combo to go with
thanks
_Zblee

 

Valve covers,coil packs, rockers and pushrods are.

But to answer your question, it really doesn't matter how aggressive your springs are, they won't wipe a lobe like an old flat tapped cam could. Their is much less friction on a roller lifter, as stated, your pushrods will go before anything.