educate me about cams

1997gtRioRed · Sep 6, 2012

so im still unsure what to do with my car. the lower end seems good, i have a bad exhaust valve on cyl#5, and it burns lots of oil, 100% sure its valve seals. so i was thinking PI heads (or engine), or maybe just have my heads redone with new valves/seals and some cams as well as some decent valve springs and retainer clips.

im really liking the comp cams Xe270AH
now, can i used stock cam gears?

do i really NEED to degree them?

how much does an average dynotune cost, and do i need a handheld tuner to have it tuned?

thanks all

Green00gt · Sep 6, 2012

ganzey said:
so im still unsure what to do with my car. the lower end seems good, i have a bad exhaust valve on cyl#5, and it burns lots of oil, 100% sure its valve seals. so i was thinking PI heads (or engine), or maybe just have my heads redone with new valves/seals and some cams as well as some decent valve springs and retainer clips.

im really liking the comp cams Xe270AH
now, can i used stock cam gears?

do i really NEED to degree them?

how much does an average dynotune cost, and do i need a handheld tuner to have it tuned?

thanks all

You can use the stock gears but I believe the bolts are TTY just like the head bolts.

You don't need to degree them but I would double check for pvt contact.

Both my lightning an gt's first tune cost around 450 and my 2nd tune on the gt when I switched blowers was only 125.

Depending on the miles on the motor I would think about new chains, guilds, tensioners, an maybe crank gear.

IPhone set

Green00gt · Sep 6, 2012

... Also i wouldn't put any money into non pi heads. You should be able to pick up a set of pi's for less te 300

IPhone set

jexey · Sep 8, 2012

Yeah it's all about a PI swap at this point, the non-pi heads are absolute dogs. That being said, talk to a local machine shop and see if they can port and polish the heads you have now for a rebuild. It doesn't really matter what heads you use for the rebuild if you p&p. It may be around the 300 you would spend for PI heads if you bought them because although you might find a set for 300, shipping is bookoo expensive since they weigh a metric ton.

twovalveterror · Sep 8, 2012

the 270's seem to be a popular street friendly cam. I've seen people who ended up retarding them a couple degrees just to increase PTVC, so you should really consider cam gears, or even some adjustable cam sprockets.

FrankenStang · Sep 12, 2012

save your time and money and just either throw in a older mark V eng or a PI eng..either of which can be had almost anywhere...the PI eng will be starit forward install so id go with that..i see them all day on craigslist for 400-1000....

00silverimposter · Sep 17, 2012

I would find a set of pi heads before doing anything with the non pi heads. I would also consider the comp 262 cams they don't make as much up top as the 270s but will make more down low and don't have to worry about ptv clearance.

BigBore96 · Oct 3, 2012

If you've got the parts to do a PI head swap do it. But, the NPI heads are not that bad. You can bolt up a PI intake and good solid NPI cam and be around the 260whp mark no problem.
For my Gt I'm going to swap PI intake on it and hunt for some good cams for the NPI heads and swap them in a day all for the super cheap. Should be pretty cool for the GF to drive around in making near stock 4v power numbers.

This is of course until the motor pops and I build a PI motor for it.

cobra clone 98 · Oct 4, 2012

what is the big difference between the non p.i head and the p.i head??

BigBore96 · Oct 4, 2012

The PI was Fords revised head style that has better exhaust flow and slightly intake ports and patterns. The NPI can accept the PI style intakes with some slight work that anyone can do. The main reason why PI stuff works better than the NPI stuff is the PI got a much better intake and better cams. Anymore due to NickMckinney at MHS keeping NPI heads is worth it as long as you throw a PI intake and some of his NPI designed cams in. Which is a lot easier than swapping heads and using smaller cams.

Unless you notch the pistons you can run a bigger cam in the NPI heads than you can in the PI heads. Which is why the NPI route makes some solid power. There was a guy who made IIRC 330whp with the NPI heads that were basically stock NPI heads, a Vic jr intake, and the custom elbow from MHS with 10.1 compression. Pretty stout for stock NPI heads.

Ninety8stang · Nov 2, 2012

I'm running the 270's in my car and they DO need valve reliefs! It only needs a slight valve relief but valve contact is valve contact. My set up is in my signature and with that being said should put you right at 300rwhp. My car put down 307hp @ 6200 and 315ftlb @ 4200 rpm, with npi 10.5cc dish pistons. If you have any questions that you might want to ask you can send me a PM if you like.

philly101 · Nov 3, 2012

So you can put don't some good na power if you port the non pi heads a run a big cam right

BigBore96 · Nov 3, 2012

philly101 said:
So you can put don't some good na power if you port the non pi heads a run a big cam right

Yes, you don't "need" porting but if the heads are off definitely mess with the exhaust side. You will need the cams degreed properly and spec'd for npi heads. They are available, you just can't pick an off the shelf comp for a PI head and throw it in without degreeing it and expect as large gains.

Also you will need to use a PI intake on the npi heads.

Cam wise you want something like this.

2V 4.6 AND 5.4 NPI NA CAMS PART NUMBER

0.050 Duration

Lift at valve

Centerlines

LSA

NPI STAGE 2.5 - NATURALLY ASPIRATED

230/233

525/525

106/112

109

twovalveterror · Nov 3, 2012

Ninety8stang said:
I'm running the 270's in my car and they DO need valve reliefs! It only needs a slight valve relief but valve contact is valve contact. My set up is in my signature and with that being said should put you right at 300rwhp. My car put down 307hp and 315ftlb @ 6200 rpm, with npi 10.5cc dish pistons. If you have any questions that you might want to ask you can send me a PM if you like.

this is good to hear. I have a very similar set up I'm planning to put on this winter. my heads are fully ported and I have flat top pistons with valve reliefs, so my goal of 300+ at the wheels seems reasonable.

what intake are you running?

philly101 · Nov 3, 2012

Has any one had any experience with mhs

BigBore96 · Nov 3, 2012

philly101 said:
Has any one had any experience with mhs

Yeah, i highly recommend them. Nick knows his stuff. Ive bought stuff from them in the past, and will continue as i need things. My gt is getting the 2.5 npi cam from them in the spring.

Ninety8stang · Nov 3, 2012

twovalveterror said:
this is good to hear. I have a very similar set up I'm planning to put on this winter. my heads are fully ported and I have flat top pistons with valve reliefs, so my goal of 300+ at the wheels seems reasonable.

what intake are you running?

I'm running frpp pi intake with a bbk 78mm plenum/tb. I honestly recommend a 75mm tb/plenum if you're running a similar set up.

twovalveterror · Nov 4, 2012

I'm considering a victor junior intake with a 90 mm tb from a 5.0. overkill, but I'm trying to do something that looks mean under the hood. still working out details as money comes in.

Ninety8stang · Nov 5, 2012

twovalveterror said:
I'm considering a victor junior intake with a 90 mm tb from a 5.0. overkill, but I'm trying to do something that looks mean under the hood. still working out details as money comes in.

90mm is going to be more than just over kill, its going to devastate your set up. unless your running forced induction 78mm is still pretty large. If you're wanting to drop the money on a bad ass intake set up that isnt "too" expensive IMO (for what it is) that makes great power and looks gorgeous you should check out the Logan Motorsports 2v intake. When i get the money thats definitely on my list of things-to-do.

its just down right nazzzzztyyyyyyyyy!