Need help with PI swap and camshaft selection please!

John1998

New Member
Joined
Mar 22, 2020
Messages
9
Reaction score
0
Hello, got a 1997 Lincoln town car 4.6 2v going in a 1998 GT. First plan was to just put cams and intake comp 268s with 500 lift and a pi intake but i Do not want to do that rtv trick on the water jackets and have a leak. I know a lot of people haven’t had problems but that still dose t eliminate the fact that it’s a weak link that I do not want. So now my second plan is to get Romeo pi heads to match the Romeo block and put the 268s in it, now I know this is close or pretty much at PTV territory and need some help deciding what will work. The heads are getting resurfaced to so that won’t help any with ptv (btw the car is only pretty much gona be a fun street car that revs to like 5800-5900) so I guess the question is should I run 268s with the 550 lift or the 500 lift or even 262s with either lift. Keep in mind that I know these have to be degreed in so the duration of the valves doesn’t interfere with the piston. I’m just kinda confused and can’t find a clear answer on this, thank you.
 

OLD H2S

Well-Known Member
SN95 Supporter
Joined
Jul 4, 2015
Messages
1,190
Reaction score
230
Location
Silver Spring Maryland
Do not worry about the leaks.. Just get a beer can and cut out the side and make a custom shaped block off plate and glue it in with Right Stuff black type.
 

Silver95bird

Active Member
Joined
Sep 5, 2016
Messages
491
Reaction score
113
Hello, got a 1997 Lincoln town car 4.6 2v going in a 1998 GT. First plan was to just put cams and intake comp 268s with 500 lift and a pi intake but i Do not want to do that rtv trick on the water jackets and have a leak. I know a lot of people haven’t had problems but that still dose t eliminate the fact that it’s a weak link that I do not want. So now my second plan is to get Romeo pi heads to match the Romeo block and put the 268s in it, now I know this is close or pretty much at PTV territory and need some help deciding what will work. The heads are getting resurfaced to so that won’t help any with ptv (btw the car is only pretty much gona be a fun street car that revs to like 5800-5900) so I guess the question is should I run 268s with the 550 lift or the 500 lift or even 262s with either lift. Keep in mind that I know these have to be degreed in so the duration of the valves doesn’t interfere with the piston. I’m just kinda confused and can’t find a clear answer on this, thank you.

I don't understand the acersion to the rtv bit, but if youre on a pi headswap route thats kind of a moot point.
Romeo heads just means you can reuse your valve covers... thats about it.

With PI heads, either lift is fine, no coil bind like the NPIs.
Degreeing the cams removes the PTV problem, thats largely why we do it, especially with aftermarket cams. How much are they taking off? If its just a clean up to make sure its flat, itnwont be much of an issue.
For a street car, I'd probably go with either of the 262's. its not the lift its the duration and timing of the valve chasing the piston down the hole. they'll be fine in that rpm range without giving up a ton of low end torque. 268s or 270s do give up more down low. Also 262s are definitely more blower friendly if you go that route some day.
262s can be advanced in their cam timing more than the bigger cams. i know the Comps have a ~5* advance ground in, which is why there are so many problems with the 270s. Tell whoever does it, if you arent yourself, to get the ICL in the 108-110 range if you can. If the PTV is tight, you might have to go more like 111-112 ish. Just take what you can get. it'll be fine.

Sent from my moto z3 using Tapatalk
 

Latest posts

Forum statistics

Threads
77,487
Messages
1,503,579
Members
14,960
Latest member
rvseverson
Top