Wait; 30>50hp from nothing but a cam-change of ; 10* extra intake duration, and 19* additional overlap, that is only meaningful with headers and a free-flowing dual exhaust? I'm just not seeing it unless the rate of lift goes off the chart, or
unless
you are including the 4bbl, the headers, and the dual exhaust.
And besides;
friend;
yur still dealing with a measly 140psi ccp. Put a 4bbl on that and watch it get soggy. Sure you could do it but why?
Just to brag on your 1000rpm powerband 318?
Any time I've seen a mild cam swap over low performance stock cam the gains have basically been everywhere they measure 2000/3000 to 5000+ rpms, not just the top 1000 rpm.
Your saying a 48* vs 51* is gonna murder the bottom end ?
What about if you carve the xe250h cam on a 107 lsa for the same 48*, shouldn't be all gain since it will have the same V/P ?
//// Explain the engines below why were not really seeing this torque loss and why we are seeing good midrange gains not just on top ? How does this square with what you are saying ?
I guess you could argue that the torque takes a huge nose dive starting at 2999 rpms and below.
I would like to see some dyno proof of that relatively mild cams killing 1500-2500 rpms.
//// Here's a BASE stock low cr 2bbl 318 with headers, MOD1 4bbl and xe262h cam, MOD2 same as 1 with spacer.
Obviously it don't show Modded 2000-2999 rpm so it's a guesstimation but this cam is two sizes bigger than the xe250h were talking about and I don't see any signs this engine has loss any bottom end. From 3000 -5500+ rpms this engine obviously dominates a stock 318.
TORQUE SUPERFLOW 901 DYNO-TESTED AT WESTECH
RPM
BASE
MOD 1
MOD 2
2,000
292
2,500
287
3,000
287
338
336
3,500
272
335
340
4,000
248
326
330
4500
218
309
319
5,000
188
285
296
5,500
250
258
HORSEPOWER SUPERFLOW 901 DYNO-TESTED AT WESTECH
RPM
BASE
MOD 1
MOD 2
2,000
112
2,500
137
3,000
164
193
192
3,500
182
224
227
4,000
189
248
252
4,500
186
265
274
5,000
179
271
282
5,500
262
270
Here's a low cr 360 from 2bbl to 4bbl and stock cam to xe250h and xe268h and don't see any signs of this low end loss.
Here's a 380hp crate with a decent size cam and 9:1 cr probably poor V/P, making fairly large 2500 rpm torque numbers 381 tq @ 2500 rpm with single plane and a 288/292 cam on a 108 lsa.