455 W30 build
#1
455 W30 build
Just got done with a real F headed 455 W30.
I lowered the compression to 9.8:1 as well as reducing the off the seat time on the cam by about 30* on both intake and exhaust.
Ran it on 91 E10 with bone stock intake and exhaust manifolds as well as pretty stock heads. Cam is a mild hyd roller, specs are 228/234@.050 on a 112. Lift is .555 on both, 34* total timing
Might try something more testing tomorrow but we’ll see😉.
Hope this helps.
I lowered the compression to 9.8:1 as well as reducing the off the seat time on the cam by about 30* on both intake and exhaust.
Ran it on 91 E10 with bone stock intake and exhaust manifolds as well as pretty stock heads. Cam is a mild hyd roller, specs are 228/234@.050 on a 112. Lift is .555 on both, 34* total timing
Might try something more testing tomorrow but we’ll see😉.
Hope this helps.
#10
Just got done with a real F headed 455 W30.
I lowered the compression to 9.8:1 as well as reducing the off the seat time on the cam by about 30* on both intake and exhaust.
Ran it on 91 E10 with bone stock intake and exhaust manifolds as well as pretty stock heads. Cam is a mild hyd roller, specs are 228/234@.050 on a 112. Lift is .555 on both, 34* total timing
Might try something more testing tomorrow but we’ll see😉.
Hope this helps.
I lowered the compression to 9.8:1 as well as reducing the off the seat time on the cam by about 30* on both intake and exhaust.
Ran it on 91 E10 with bone stock intake and exhaust manifolds as well as pretty stock heads. Cam is a mild hyd roller, specs are 228/234@.050 on a 112. Lift is .555 on both, 34* total timing
Might try something more testing tomorrow but we’ll see😉.
Hope this helps.
#12
Ok, so I had the opportunity to go from the W Z manifolds and 2.25” pipes to headers and 2.500” pipes. Anybody want to guess the HP/tq difference and where in the rpm range? REMEMBER, stock intake, stock exhaust, OPEN crossovers, Hint, I was genuinely surprised based on my previous experience doing the same comparison on other builds.
Let the speculation begin!!
Let the speculation begin!!
Last edited by cutlassefi; March 20th, 2021 at 03:49 PM.
#14
#15
Pure guess would be 20-30 ft-lb. I'm kind of torn about the RPM range. I can make a case for low and for high. Given that the intake side is probably choking the high end, I'm going to say biggest improvement at the bottom of the pull.
#16
Ok we have one entry, anyone else?
#17
I’ll guesstimate an improvement 28 lbs ft at around 3300 rpm, snd 35 hp at 5200. Is that a specific enough guess?
Come on guys, share your guess. This is much more fun if everyone shares their thoughts.
I have the Jeopardy theme in my head.
Come on guys, share your guess. This is much more fun if everyone shares their thoughts.
I have the Jeopardy theme in my head.
#18
#20
#29
Here you go guys. I have a theory about why the results are what they are as well as the effect that an open exhaust cavity has on power and tq and where.
The top pull was done with 34*, the bottom pull was with 32*, go figure.
Last edited by cutlassefi; March 21st, 2021 at 06:53 AM.
#31
Neither my eyes nor my monitor are that good...
#32
W/Z manifolds are better than most factory exhaust manifolds, due to the internal runners. I'd guessed that the short "tubes" in those manifolds would actually be biased towards the high end, thus the lack of improvement with headers there. I'm curious why the headers seem to nose over at the top end. Is there some weird resonance in the long-tube primaries?
#34
W/Z manifolds are better than most factory exhaust manifolds, due to the internal runners. I'd guessed that the short "tubes" in those manifolds would actually be biased towards the high end, thus the lack of improvement with headers there. I'm curious why the headers seem to nose over at the top end. Is there some weird resonance in the long-tube primaries?
I believe the better scavenging of the headers pays off more at the bottom end because of the open cavity in the heads and intake and the overall traditional effect headers have on an engine. Add to that, as you pointed out, the intake tract on this is somewhat challenged, hence the minimal gain up top.
#37
#39
You don't know why he chooses not to do that. You're starting those passive aggressive statements again.
I've read some of your other posts and am impressed with what you have done. You have nothing to prove, so don't act like you do.
Again, this is not ROP--drama is not considered a benefit here.
I've read some of your other posts and am impressed with what you have done. You have nothing to prove, so don't act like you do.
Again, this is not ROP--drama is not considered a benefit here.