ntrsrich302

is there a way to tell if you did not degree your cam correctly?
does low vacuum tell you your too advanced?
306,.030 trw piston w/relief cuts,1.6 rr, windsor Sr heads,springs good to .600 lift ,XE274hr,GT-40 intake,with 1 inch spacer.
or does this cam always run low vacuum?
am running around 10 to 12 inches of vacuum at idle. very good bottom end but out of steam at 58k or less.

AdderMk2

gt-40 intake isnt exactly a high RPM piece...

ntrsrich302

this is a street car .. that intake is fine for my application ..

Bubba 95SN

Throttle body and size of ports on intake are a limiting factor...

Samuel20

IM NEW TO THIS CAN SUMBODY PLZ TELL ME HOW TO POST STUFF.!?

mjr46

lol....then live with 5800 rpm.....you can only **** through a straw so fast

ntrsrich302

what the heck does this have to do with what i ask?

mjr46

you state it runs out of steam at 5800, that's what the heck it has to do with what you asked, cam timing if degreed or with that cam set dot to dot should be close = cam timing is most likely NOT your problem.

ntrsrich302

If you read. I ask about low vacuum. I get different answers on vacuum some say it should pull at least 17 inches or more. I am only at 10 inches to 12 at best. I asked if this cam just has low vacuum. That intake is good to about 6k or less which shifting should be right at 58k or so because when you shift it's prolly higher to keep from rpm drop. I know less vacuum would be a vacuum leak. Between 10 to 15 might be over advanced timing?

mjr46

If I read..lol ...noobs.........anyway, let me explain since you can't draw a line to what I'm getting at.....now assuming you've assembled the engine properly and it is running fine and your only issue is running out of steam a little early therefore causing you to think over advanced cam timing is your issue, , I ran an xe282 cam for a while, = 1 step above the 274 and it pulled 9-11 inches of vaccum, don't expect your 274 to pull anywhere close to 17, whomever told you that is a moron, the valve overlap on the 274 is such that , the vaccum signal won't be a strong 10-12 is close (there you happy, is that the answer you seek affirmation of??) lack of rpm potential can be attributed to how efficient the parts work well or lack thereof together........A gt-40 lower is no different than a stock cobra and the port size unported is less than desirable, furthermore, how is port transition?? did you bother to look at that = head port vs intake and once it is on the transition points?? I use a mirror or borescope for such often times.....your heads and cam may have the ability to get the a/f into the cylinders effectively but the bottle neck of the t/b or intake may not, also a restrictive exhaust can hamper the whole set up to, you make no mention of exhaust set up??......I ran a similar set up in comparison with yours, heck I ran the smaller rpm heads 1.90/1.60 and a custom cam with comparitive specs to the 274, only mine has less duration, and I ran a ported cobra at first, that quickly went, added an rpm 2 and now it pulls easily past 6k...I also made sure port transition was spot on and exhaust was not smallish/restrictive...to each his own and good luck

ps: cam timing could effect where the power fall off is advanced to far could lower it but you've made no mention of where you set it at, if you set it dot to dot as I did with my 282 only after the degree wheeel confirmed it then you most likely are fine and I'd look else where, but did you degree the cam to check the valve events??