He's maybe accessing the .450 area of flow in those heads.
Maybe the injection is holding it back.
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When good is not enough, Camshaft time again.
- Thread starter Kent mosby
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He's maybe accessing the .450 area of flow in those heads.
Maybe the injection is holding it back.
PRH
Well-Known Member
I checked out the Hughes site.
It sure does seem like the 24-30HD should be able to hold your combo down below under 4500 flash stall.
Have you ever discussed the stall speed of that converter behind your combo with them?
If so, did they seem to indicate it was normal?
It sure does seem like the 24-30HD should be able to hold your combo down below under 4500 flash stall.
Have you ever discussed the stall speed of that converter behind your combo with them?
If so, did they seem to indicate it was normal?
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never thought about it as I am unaware of the ins and outs of TQ. still learning all this.
He needs to take it to Ernie and get it on the chassis dyno for some tuning.
He's running the Holley Super Sniper EFI
I will take it to him after I get a better cam in it, if it does not respond as expected. I have spoken to him earlier and he said that he was not fixing mechanical issues but would tune it for both driveability and high performance. Thus, I want to be sure that the cam is not the issue. Tuning it only to find out it is a cam issue throws $900 or so out the door.
I would be happy with 11.0 and 123. I have many time slips but no DAs. My budget is flexible but I do not want to go with a solid roller. After the Cam, I will assess what I have and may consider the TQ. The fuel is fine according to the datalog there is no loss of fuel pressure all the way. Less than 2000 miles total on the car and about 80 runs on the 1/4. Thanks for the insight. I am always learning
mayhem
Well-Known Member
That's what I was thinking too. Not apples to apples but aren't the Gen III Hemi cars faster with carb(s)?
Jeremiah (jd)
Well-Known Member
I would look into a hydraulic roller setup utilizing comp Evo lifters. I'm not 100% sure what folks are getting away with concerning valve spring pressure. I owned a stock stroke 440 with a hydraulic roller cam (unknown specs) and was impressed with it's manners and power output. This would be a viable low maintenance option.
If you put a bar in it definitely gap the rings for nitrous!!
If you put a bar in it definitely gap the rings for nitrous!!
The TF 240s are 600-650 hp heads. I'm sure you're quite aware. Going from 600 crank, to the back wheels, assuming a 15% reduction, you ought to be 510 hp minimum at the wheels. You're missing a lot of power somewhere.
To me the tell tale is the torque. It should at least hit the torque number with the displacement, even under cammed a bit it would shift the torque curve down wouldn't it?
What other diagnostics have been done? What are cranking compression, leak down numbers? Since you've been on the dyno I'm assuming you've done timing and AF sweeps to optimize tune. Key word assuming.
To me the tell tale is the torque. It should at least hit the torque number with the displacement, even under cammed a bit it would shift the torque curve down wouldn't it?
What other diagnostics have been done? What are cranking compression, leak down numbers? Since you've been on the dyno I'm assuming you've done timing and AF sweeps to optimize tune. Key word assuming.
mygasser
Well-Known Member
nice, or even an 8/71 blower or if you like a flat hood then a couple of turbos? mmmmmmm.....
We have done timing and af adjustments during tuning but not on the dyno. When degreasing the cam I checked compression and it was good. I don’t remember the numbers. No leak down testing. I will be disassembling this weekend to inspect everything and prep for a new cam. Any other baseline testing or info I should record prior to removing parts?
I'm kind of scratching my head on this one.
Sure a fresh set of compression numbers would be a good idea. Especially if you don't recall. At least you'd have a before and after indication.
I'm also assuming this is an otherwise we'll behaved combo. No other weird issues like overheating or instability. You seem like you know what you're doing.
Just seems like something is robbing a bunch.
It runs well, just underpowered . No issues with cooling/overheating except at a car parade in 105 degree temp when you are literally not moving for 5 minutes at a time. After a half hour it starts to get hot. Around town or at the track, no issues. I will get compression numbers prior to disassembly. After I get the cam out I will inspect and measure lift as well to see if I have something wrong there.
I think I would try to find someone with a Holley 950HP that would let you try it.
The efi is working well. Trying to remove all of that would be a major issue. Yet, if after the cam change there is still no power, I would consider anything.one thing at a time.
I wonder is that with sae1349 or std 607 correction factor?
An engine is just an air pump. Cams will increase/decrease/move around where it flows air but in the end, the OP still has a 512 inch air pump. That thing HAS to move a bunch of air at that displacement (and thus make big numbers).
So no overheating or other issues that would indicate some type of high internal friction. And tuning has been done to dial in what the engine is seeing. And assuming the cam is not fubar, meaning the lobes are ground where they're supposed to be and it's operating properly, the engine just HAS to put up bigger numbers than 400/400. Has to! I'm with @Mean416 scratching my head on this one!
So what's left is either a cork on the front side or the back side. I'm not familiar with the EFI system on it. Is its flow rating sufficient for that size engine? Do the throttles truly get to WOT?
At the track, do you run it through the mufflers? If so, I'd drop the exhaust down at the collector, hang it by 1 bolt like I (and many others on here!) did in the 70's-80's, and make some passes to see if there's some type of cork in the exhaust. SOMEWHERE, there's a cork!! That engine just has to make big numbers!
So no overheating or other issues that would indicate some type of high internal friction. And tuning has been done to dial in what the engine is seeing. And assuming the cam is not fubar, meaning the lobes are ground where they're supposed to be and it's operating properly, the engine just HAS to put up bigger numbers than 400/400. Has to! I'm with @Mean416 scratching my head on this one!
So what's left is either a cork on the front side or the back side. I'm not familiar with the EFI system on it. Is its flow rating sufficient for that size engine? Do the throttles truly get to WOT?
At the track, do you run it through the mufflers? If so, I'd drop the exhaust down at the collector, hang it by 1 bolt like I (and many others on here!) did in the 70's-80's, and make some passes to see if there's some type of cork in the exhaust. SOMEWHERE, there's a cork!! That engine just has to make big numbers!
The head scratching is why I need to remove and check the cam the heads should flow and the tti headers are big as well as the race pro mufflers. Hopefully this weekend I can get the cam out and inspect everything. Might be 2 weekends. Our track is shut down for the year so this is my winter project. If I get the cam out and all is good, a run with open pipes may happen in the spring.
Also transmission, torque converter, and rear end, accessories can create losses. I'm not an expert enough on transmissions to know what to look at there. Excessive heat would be an indication though. Got a temp gage on the trans? How's the fluid smell?
Yep. 400ft lbs would be weak for a 408 much less a 500 inch big block.
A failing cam you would see degradation in performance and there would be other signs as well. Especially given that you've made 50 passes with the combo. You wouldn't expect it to be well behaved. Let's just say that. Noises stuff in the oil etc.
Is this a solid cam? Have you checked the lift pulling a valve cover off? Do that on all 8 cylinders. If there's a flat lobe or two you would be able to see it.
Yes, the transmission does not heat up much. Only get to 185 and the trans cooler keeps it below that. Never goes much higher. The fluid is good. I had parking pall lever slip and had to drain the pan this past spring and no issues/debris in the pan.
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