3400 TAKE 2! BANG!

[gpse3400]

Installed it in my GP a few days ago. Started on the first try. Basically the same thing as the last setup but with a more aggressive profile cam and a HV oil pump. The valvetrain is surprisingly quiet, idle is about as good as it was before. The overall sound of the engine is different, esspecially at lower engine speed. Like it's working much harder. Nice sound to it. Power has increased all across the board due to way reduced blow by and the new cam. Kinda has like 3 tiers of power, Strong on the bottom, builds at 3500 , then rebuilds at 5000. Trans shifts too early at 7000. But hey I'll let it. I don't feel like running any higher. Here is a list of the things done to it. Like I said those that know before will see little changed.

3.4 Iron head pistons,
Crane regrind of a more agressive profile. (.525/.540 lift)
Custom pushrods(to added later next week)
LS6 valve Springs
HV Clevite oil pump(Pressure avg now at 60 psi at NOC)
Reman Crank
New AC Delco roller lifters
ACDelco Double Platinum Plugs(colder set)
Old GEN3 timing set(switched off from the newer set with the thinner chain)

Reman Heads
62mm FDP TB
2.5in exhaust from the manifold to the Y plus Catalyst
2in Hooker AeroChamber Mufflers
3.73 FDR With Sonnax FD sun gear

Well can't wait to run it down the strip. I don't know it sounds like a winner...Get some pictures and sound clips later on.

[geoffinbc]

Got cam specs?

[gpse3400]

LS112, Duration 232/328in, 238/337ex. Lobe lift .328in, .337ex

[geoffinbc]

Wow sounds like a pretty good screamer.

[quantum110]

Power has increased all across the board due to way reduced blow by and the new cam. Kinda has like 3 tiers of power, Strong on the bottom, builds at 3500 , then rebuilds at 5000.

Umm, Get it dyno'd, because that makes no sense. Unless you have a Ignition or fuel problem.

[SappySE107]

What tuning are you running? My latest, or your latest?

[3100 MPFI]

Power has increased all across the board due to way reduced blow by and the new cam. Kinda has like 3 tiers of power, Strong on the bottom, builds at 3500 , then rebuilds at 5000.

Umm, Get it dyno'd, because that makes no sense. Unless you have a Ignition or fuel problem.

What do you mean?

He has a problem because of the way the cam does?

Does that mean that I have a problem also seeing that my 3100 has no power under 4000 RPM, and pulls all the way to 7000 RPM?

When you get into the more extreme cams like lorenzo did, then it can do some weird things with the powerband. With Lorenzo's last version of the engine, his 3400, and my 3100 were identical with the exception of the displacement. We even had the same cam profile, but driving out cars were like night and day. He had a lot of bottom end, but I had a lot of top end.

[quantum110]

What do you mean?

He has a problem because of the way the cam does?

Does that mean that I have a problem also seeing that my 3100 has no power under 4000 RPM, and pulls all the way to 7000 RPM?

When you get into the more extreme cams like lorenzo did, then it can do some weird things with the powerband. With Lorenzo's last version of the engine, his 3400, and my 3100 were identical with the exception of the displacement. We even had the same cam profile, but driving out cars were like night and day. He had a lot of bottom end, but I had a lot of top end.

This way he's describing the power though...it builds to 3500, then flatlines for 1500rpm, then builds to 7k. I can understand small 50rpm or so spikes, but a 1500rpm flatline seems weird.

Now lets tak a look at your 3100 vs his old 3400...the key here is that difference in displacement. A lager displacement engine will utilze more airflow than the smaller. Thus given the cam you used the small engine will perform better on the top end, because the lager one is probably trying to flow too much for it.

[gpse3400]

.........Well to answer Ben's question....I'm using my altered program which I need to not be using because the ign timing is still set to autodestruct. I haven't ran the lapy with it yet as I don't know whats going on with the the compy. But it does start smoke free....I can at least say that.

To elaborate....The power production is not a flat lining feel by any means. I just notice the rate of acceleration changing the higher you wind it at certain engine speeds. It isn't abrupt but smooth. Eitherway if it is a problem, then checking the fuel and IGN I'm sure would fix it. I've done that before to be sure....

[AaronGTR]

Whats this difference in the GEN3 timing sets you're talking about? Didn't see it mentioned anywhere in changes in the 60v6 family tree. Something about different chains... any idea when they made the change? I have a 2000 built 3400 that I'm installing a cam in soon, and even though it doesn't have a lot of miles everyone keeps telling me I should replace the timing chain. If I do replace it I wanna make sure I get the best part, so I'd have to see if I can still order the old style. Just need to know what year to look for and what the difference is.

[Froggx]

What do you mean?

He has a problem because of the way the cam does?

Does that mean that I have a problem also seeing that my 3100 has no power under 4000 RPM, and pulls all the way to 7000 RPM?

When you get into the more extreme cams like lorenzo did, then it can do some weird things with the powerband. With Lorenzo's last version of the engine, his 3400, and my 3100 were identical with the exception of the displacement. We even had the same cam profile, but driving out cars were like night and day. He had a lot of bottom end, but I had a lot of top end.

This way he's describing the power though...it builds to 3500, then flatlines for 1500rpm, then builds to 7k. I can understand small 50rpm or so spikes, but a 1500rpm flatline seems weird.

Now lets tak a look at your 3100 vs his old 3400...the key here is that difference in displacement. A lager displacement engine will utilze more airflow than the smaller. Thus given the cam you used the small engine will perform better on the top end, because the lager one is probably trying to flow too much for it.

I'm sure everyone has seen this but:

http://fiero.cc/fiero-tdc/members/mws/intake/index.html

He has 1500 rpm where his torque and hp don't really flatline, but it does actually build, drop, and then build again.


edited for screwing up...

[Rhedalert]

EEEEAAAA!HHH!! I gotta see this thing :willynilly:

[gpse3400]

Whats this difference in the GEN3 timing sets you're talking about? Didn't see it mentioned anywhere in changes in the 60v6 family tree. Something about different chains... any idea when they made the change? I have a 2000 built 3400 that I'm installing a cam in soon, and even though it doesn't have a lot of miles everyone keeps telling me I should replace the timing chain. If I do replace it I wanna make sure I get the best part, so I'd have to see if I can still order the old style. Just need to know what year to look for and what the difference is.

It might've been a mid '00 thing. They went to a thinner timing chain. Yet the sprockets have more teeth. It still looks sturdy, I think they made it like that for sound purposes. The older style chain is as thick as a GEN2 chain...I've used both. I figure I wanted a new set and the older style is cheaper. Also twice the thickness. The previous run of my engine had the thinner chain. I'll try to get some pics of the newer style I have lying around...I don't know I think they might be about as good as the other, I know the smaller chain kinda shines more that the older one so I can only assume different materials. The sprockets are also a bit differnt in composition.

[gpse3400]

EEEEAAAA!HHH!! I gotta see this thing :willynilly:

Haha Jerky!!!lololololololol "Just call me on the phone in the truck."

[RidgeRunner]

Sounds like a beast, Lorenzo. Refresh my memory, what happened to the old 3400?