matt_jahn

i know these are supposed to move the power band up quite a bit, so why do i feel like it runs out of power at 5700 or so rpm. i have a pcmforless tune had rev limiter raised to 7000, not going to take it past six till i get heads with better valves. but shouldn't this cam in an lt1 rev past 6000 and be pulling hard.

856SPEED

How do you know? "Seat of the pants" feel is not an accurate measure....put it on a chassis dyno and see where the torque/horsepower levels off of at what RPM......that will give you the answers you are looking for.

93sandiego

I know on my 2001 camaro with the turbo added and 18,000 miles on the car during the dyno tune i started flattening out and loosing power at 5600 rpm. This was do to valve springs swithed to titanium retainers and stronger springs and picked up almost 100 hp and was still making power at 6400 rpm. btw added 2lb of extra boost also. So maybe if you have high miles your springs are weak.

matt_jahn

well i put the lt4 springs in but i feel like like its missing or backfiring at 5700

cv67

Check your fuel pressure under load.

Who told you that cam would go anywhere NEAR 7000?


Its a smallish hydraulic not a big solid

CAJUN C4

If your running stock LT1 heads it's being choked.Air can get in but not out.

matt_jahn

I'm not gonna rev it to 7. I heard makin power to 6400. And as for getting air out, I have hooker shorties magnaflow cats and cat back

Or are you saying the exhaust side of the head is restrictive

96 lt-4

Could be many things.Weak spark,detonation causing the computer to retard timing,too lean from not tuning after cam install,etc.
It should turn 6000 if all else is well.
Like said get it on a chassis dyno or some tuning software and see what it is doing.

matt_jahn

I'm much more comfortable with obd2 cars. But does anyone know if I could wstch o2s readings and knock retard on a 92 with a tech 2, with The right obd1 connector. I know it will on some later obd1 models

mtwoolford

and they call this progress

my 1961 with a 365 horse short block 327 and a duntov 30 / 30 cam pulled 7,000 no problem; the problems began at about 7,200; better timing chains or a gear drive and god knows what that engine would have revved to.

1963SS

Howdy, Matt. As to your original post, the shorty headers aren't much better than stock manifolds. Your stock heads only have about 160 cc(or so) runners. Just changing a cam doesn't do much at all for your engine. There are tons of supporting mods that are required to make it run correctly. I would think that 5600 or so would be all she had. You're not making as much power at 6400, as you stated, as you are at 56-5700.You can rev more but you're flogging a dead horse. You need to turn Lloyd loose on those heads, spec a hotter cam, roller rockers, long tubes, and 30# injectors.

A lot of times, many people have put bigger cam in a stock engine and lost drive-ability and made less usable power than they had. Listen to a lot of the folks on this forum. They know a lot and can help you find the cheapest way to make the most power.

Sure, the earlier 327's and 302's could rev to the moon but they had solid lifters. The 64-65 327/365 were great engines for their time. I was graduating when they came out. The 1969 302 made almost as much power and could easily rev to 7200. I bought a new 69 Charger R/T with the 440 Magnum when I came back from overseas. My buddy bought a 69 Z28 and he spanked my Charger every time we tried each other. He supposedly had 290 HP and I had 375. That's the biggest BS horsepower number Chevy ever lied about. Those little mouse motors were badass.