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these engines can take a detonation.
my friends 90 grand prix 220k miles and runs lean like a mofo, and there's some detonation in there
Are you talking a boosted motor? You haven't heard the kind of detonation that can be had from lean @ 5pisg It sounds like 1/2 stick of dynamite, believe me. It crushed a bearing in my car
Are you talking a boosted motor? You haven't heard the kind of detonation that can be had from lean @ 5pisg It sounds like 1/2 stick of dynamite, believe me. It crushed a bearing in my car
And made my 3.4L pistons look like what you see on the second page of this thread.
I remember that thread . I haven't taken the heads off since this last episode, but I'm curious to see what has survived. I'll post some pics when it comes apart. I hope the block doesn't need to be bored :P
ive been boosted for year and a half on my 3400 and its still strong. i am NOT easy on this car at all. made 358 whp on 9 psi BONE STOCK bottom end. they can take detonation...
4yrs at 7-8 psi at the intake manifold on a 3100 with iron heads in a fiero. I don't know what the power output is but I know what the shifting and rpm has been like over that time and there is nothing cute about it.
ive been boosted for year and a half on my 3400 and its still strong. i am NOT easy on this car at all. made 358 whp on 9 psi BONE STOCK bottom end. they can take detonation...
How the H3LL are you making more power than a 3.4dohc turbo and a 3.8 (series 2) turbo with only 9psi? Not trying to start nothing but this has been a big controversy for a lot of people using this numbers which are NOT logical. In other words you are making 400 hp at the engine with 9 or 10 psi. Don't take this the wrong way, I have seen your dyno and it shows nothing to the contrary.
a.) you are either not reading the right pressure
b.) you dynoed on wrong gears (2nd)
c.) some smells fishy
I will choose b.)
Of course I am assuming stock heads, stock cams. Do you care to elaborate, fuel system also?
How the H3LL are you making more power than a 3.4dohc turbo and a 3.8 (series 2) turbo with only 9psi? Not trying to start nothing but this has been a big controversy for a lot of people using this numbers which are NOT logical. In other words you are making 400 hp at the engine with 9 or 10 psi. Don't take this the wrong way, I have seen your dyno and it shows nothing to the contrary.
a.) you are either not reading the right pressure
b.) you dynoed on wrong gears (2nd)
c.) some smells fishy
I will choose b.)
Of course I am assuming stock heads, stock cams. Do you care to elaborate, fuel system also?
No matter what the rational, a 12.5 second quarter mile time says more than a dyno print out, and the 3.8L iron engine does not compare, if it had the efficiency that the 3400 does it would produce a heck of a bit more power than it does on the same boost pressure it currently runs. HP performance offers a turbo kit for the stock 3400 in the Grand Am that put down 264 hp and 284 lb/ft at the wheels on 9 psi, that's 4 more hp and tq than the 3800SC puts out at the crank with a .4 litre advantage in case you question which engine is more efficient.
A properly matched turbo with sufficient intake charge cooling and a good exhaust system can get more out of the stock 3400.
There are several people with 3400's that have dyno'd over 300whp so why is another 58 so impossible?
An aggressive tune and a good sized turbo, I think it is very possible!
I am curious myself can you please list these people and state their respective mods if you will...thanks
Originally posted by Joseph Upson
No matter what the rational, a 12.5 second quarter mile time says more than a dyno print out, and the 3.8L iron engine does not compare, if it had the efficiency that the 3400 does it would produce a heck of a bit more power than it does on the same boost pressure it currently runs. HP performance offers a turbo kit for the stock 3400 in the Grand Am that put down 264 hp and 284 lb/ft at the wheels on 9 psi, that's 4 more hp and tq than the 3800SC puts out at the crank with a .4 litre advantage in case you question which engine is more efficient.
A properly matched turbo with sufficient intake charge cooling and a good exhaust system can get more out of the stock 3400.
LOL...Joseph you are very well read but I think this matter has got to meet some real analysis sooner or later. A 12.5s quarter mile says nothing but a potential of both the car and more towards the driver. I cannot discount the mph...I have heard and seen two videos that have captured ONLY two cars with the prescribed combo (3400 and a turbo). Look at the consumption chart of a 3400 and look at one of a natural aspirated S2 3800...what the bigger engine lacks in so called efficiency it makes up plenty in displacement when force inducted viz turbo. We are comparing natural aspirated engines mind you...more importantly, no matter how good one can port heads...it will not match that of a 24-valve engine and yet for this engines to make the aforementioned hp one needs definitely more than 9psi.
I would not say it is impossible, but show me the physics...several ppl have turbocharged stock 3100s, 3400s, 3.4s, 3800s; to get this kind of output for inefficient engines as mentioned requires more than I have seen here. Again we are not talking ideal engine...we are talking why this one or the other (apparently rear mounted) defied outputs that have been thoroughly documented in the past?
I didn't mention the 3.4 DOHC because I would need to see proof in that comparison also. In regards to physics and formulas we both know that naturally aspirated induction vs. forced induction produces very different results regarding flow dynamics, where boring out the intake and heads may ruin over all performance in a naturally aspirated engine but the same engine under boost would very likely result in significant power increase due to the the inverse manner in which airflow tends to behave under those circumstances when it is being sucked in compared to when it is being pushed and in my opinion and observation so far the flow character for the 3400 compared to the 3800 seems to be better under boost.
Mind you I'm ignoring the area under the curve at the moment, I just feel the tiny little 60 degree package does a hell of a job making power.
12.5 sec quarter mile means you have something real under the hood, or a very low power to weight ratio, either one is comendable, a 400 hp dyno sheet means nothing more than potential to me especially if it fails at performing at the track because it was in the wrong gear on the Dyno.
Both are good engines, I like to use formulas also for more accurate comparison but I left my phys book at home.
I noticed the 3.6 DOHC is very popular for GM in 08, as well as the 3500 both serving as the base engine for several cars. There has also been a cut in power since the previous year and no 3800SC option.
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