Take a Guess!
04-04-2012, 06:25 PM
#1
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Take a Guess! I know you all hate hearing this!
Take a guess on what it should be making !
Lsx block 427
afr heads 225 72 cc
fast intake 102
42 lbs injectors
96 mm throttle body
mamo cam 639 639 lift 239 duration 114+1
rear wheels of g8 made 410 threw 6180 and 2500 hughs stall!
Take a guess on what it should be making !
Lsx block 427
afr heads 225 72 cc
fast intake 102
42 lbs injectors
96 mm throttle body
mamo cam 639 639 lift 239 duration 114+1
rear wheels of g8 made 410 threw 6180 and 2500 hughs stall!
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04-06-2012, 08:38 PM
#12
I agree....
A list of all the components (at least the major ones) and a clear picture of the dyno graph would be very telling information.
I suspect valve float as well which has also been mentioned already.
-Tony
A list of all the components (at least the major ones) and a clear picture of the dyno graph would be very telling information.
I suspect valve float as well which has also been mentioned already.
-Tony
04-07-2012, 05:19 PM
#13
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Update Motors Story 427 lsx block
afr heads 225 72 cc
weisco -11 dome pistons
fast 102 intake
90 mm ported and polish throttle boddy
1/7/8 headers
tony mamo cam 239 -239 629 lift 114+1
I just got this info from the motor builder today not the seller of the car!
I am thinking compression is kinda low there as well with that head and -11 cc dish 10.20 to 1 or so !
Any help on how to get on track would be amazing !
afr heads 225 72 cc
weisco -11 dome pistons
fast 102 intake
90 mm ported and polish throttle boddy
1/7/8 headers
tony mamo cam 239 -239 629 lift 114+1
I just got this info from the motor builder today not the seller of the car!
I am thinking compression is kinda low there as well with that head and -11 cc dish 10.20 to 1 or so !
Any help on how to get on track would be amazing !
04-07-2012, 08:01 PM
#16
Can you have your tuner/dyno operator scale the HP and TQ the same.....he can do it on the computer and email you the same file so its easier to read.
What rockers are you running.....compression is low as you realized already. Why was it built/set up that way (a boosted deal is the only thing I can think of).
You are getting valve float up top....
First thing I would do is check cranking compression in 2-3 cylinders to verify its consistent. I would be curious would that figure is.
The engine is making really poor torque down low.....I would consider rolling it on another dyno also.....a known dyno in your area ideally, or ask this dyno operator to show you a car on his dyno that we already know should be around "X".....like a stock C5 Z06 for example which is typically 350 - 360 RWHP.....is that car the same on his dyno or is it closer to 300. A big unknown at this point is the dyno but the power and torque curve itself doesnt look very good regardless.
Cranking compression first....maybe even a leak down to check the condition of your ring seal.
I would verify dyno and how it compares to "typical" stuff.....the cranking PSI, and the leak down first before any thought is spent elsewhere.
Those are the basics and all of that info is critical in diagnosing what looks to be a very soft result at initial glance till we do some digging as to why.
What condition are the heads also....where they aver messed with by a shop that might have screwed up the valvejob. Stock 225's are easily capable of 500+ RWHP....many before you have achieved that and the better more detail oriented combos are in the low/mid 500's on strokers the same size as yours.
Time to do some digging....
-Tony
PS....To be honest with you, looking at the torque curve, specifically the low end torque which even with a crappy set-up is always decent when you have 400+ CID of displacement....this engine looks more like a so-so 346. Its almost impossible to have that low a torque number under say 4K with a 427 CID engine. I wonder if the cam is off a tooth or something. If this is really a 427 and the dyno is even remotely in the ballpark of average, this engine is not healthy and needs to be torn down to figure whats what. Once again though.....that assumes the displacement is legit and the dyno is not the stingiest dyno on the planet.
What rockers are you running.....compression is low as you realized already. Why was it built/set up that way (a boosted deal is the only thing I can think of).
You are getting valve float up top....
First thing I would do is check cranking compression in 2-3 cylinders to verify its consistent. I would be curious would that figure is.
The engine is making really poor torque down low.....I would consider rolling it on another dyno also.....a known dyno in your area ideally, or ask this dyno operator to show you a car on his dyno that we already know should be around "X".....like a stock C5 Z06 for example which is typically 350 - 360 RWHP.....is that car the same on his dyno or is it closer to 300. A big unknown at this point is the dyno but the power and torque curve itself doesnt look very good regardless.
Cranking compression first....maybe even a leak down to check the condition of your ring seal.
I would verify dyno and how it compares to "typical" stuff.....the cranking PSI, and the leak down first before any thought is spent elsewhere.
Those are the basics and all of that info is critical in diagnosing what looks to be a very soft result at initial glance till we do some digging as to why.
What condition are the heads also....where they aver messed with by a shop that might have screwed up the valvejob. Stock 225's are easily capable of 500+ RWHP....many before you have achieved that and the better more detail oriented combos are in the low/mid 500's on strokers the same size as yours.
Time to do some digging....
-Tony
PS....To be honest with you, looking at the torque curve, specifically the low end torque which even with a crappy set-up is always decent when you have 400+ CID of displacement....this engine looks more like a so-so 346. Its almost impossible to have that low a torque number under say 4K with a 427 CID engine. I wonder if the cam is off a tooth or something. If this is really a 427 and the dyno is even remotely in the ballpark of average, this engine is not healthy and needs to be torn down to figure whats what. Once again though.....that assumes the displacement is legit and the dyno is not the stingiest dyno on the planet.
Last edited by Tony Mamo @ AFR; 04-07-2012 at 08:07 PM.
04-07-2012, 10:17 PM
#19
Certainly not healthy. That's lower than the power I got out of my 346. AFR looks a tad lean above 4500 as well. What kind of exhaust setup do you have. Mine is overly restrictive and managed 420WHP.
As for the "Tuned by Frost"< I've talked to him before and is a pretty nice guy. But he'll say what we are all thinking. Something mechanically is amiss there and he cannot help until it is sorted.
As for the "Tuned by Frost"< I've talked to him before and is a pretty nice guy. But he'll say what we are all thinking. Something mechanically is amiss there and he cannot help until it is sorted.