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I took a look at his dyno graph it looks like he made the same power up to 5800rpms thats the point my cam is running out of stem. Now I know you may say intake or exhaust. I'm going with cam.

Also this is his comment #83 ((Thats not what I'm looking for or calling a street car)) Not hating sweet car just not what I want to do.
With the big cam, my engine was shaking quite a bit at idle with the Energy Suspension motor mounts. I bought a Moroso torque link to use at the track and it ended up making the car much more pleasant to drive. There was less shake and vibration under normal driving conditions when the engine was physically bolted to the frame rail.

I bought and installed some Holcomb Motorsports solid motor mounts last week and I am very pleased with them. They are the standard height solid mounts and they kept the engine at the exact same height as the Energy Suspension mounts they replaced. The car has much less shake and vibration during idle and while driving on the street. Solid mounts may not be right for every combo, but they are great for mine.
I understand what you're saying, but his cam really isn't "big" - it's 240/248 ~.570 lift on a 112. Mine is 228/242 .600 lift on a 116 - yours, if I recall, is similar to mine. 12 degrees of duration isn't insignificant, but it's not much (we don't know the ramp speed, but it's still a logical comparison). 12 degrees isn't going to get you 50hp, much less the 150+ you need. Also, you can't compare his numbers below about 6,000 rpm. Remember, he's running an unlocked auto - the converter's not even coupled yet. That first hump is where the converter hits flash stall, the dip after is the recovery, and then by about 6,000 rpm, the converter's actually started to couple - but even if it's "tight" it's still slipping at least 8-10% in all likelihood; if not more. I see around 12% slippage at peak power in my car. To do an apples to apples comparison, you have to add AT LEAST 10% more power to Dean's graph to match your tranny. He's making at least 575 flywheel horsepower. You're making around 420 flywheel hp (I'm not using your dyno info because, quite frankly, it's bullshit). I make around 480 flywheel hp (that's with the shorties - I put the Kook longtubes in last night - I'd 500 would be a fair, conservative number for me now). Anyway, he's an easy 155 hp up on you. I've been guessing up until now, but now I just ran the numbers. Even if we're very generous and give his cam a 50hp "value," he's still over 100 hp up on you if discount the cam differences - and I think it's more like 120-130. There's also the fact that his pulls are SAE, and yours are unknown. Comparing an SAE graph to your dyno graph is grossly inaccurate (the errors compound in your favor, which is why you want to believe those numbers; I'm going to stop asking about your correction factor since you won't answer that question and I've asked several times). As I've said before, the track doesn't lie. He's got 16 mph on you. Using the 10hp/mph "rule of thumb" (though in this range it's more like 12hp), he's 160 hp up on you. Either way, you're leaving A LOT on the table.

There's another way to confirm these numbers. What's your injector size and duty cycle? We can easily (and quite accurately) figure it out from that too.

FWIW, I run solid mounts too, and they smoothed things out for me as well. My car idles so nicely I don't even run an IAC of any sort. I take care of it with my ignition tables (your tables do the same thing). See my tables above for reference.

Bottom line - the track doesn't lie and you're still leaving a ton of hp on the table. Leave the cam alone and put a good intake on it. You've got an excellent longblock and you've topped it off with a Burger King crown. If you're hell bent on retaining that Cobra look, then that's fine. But 120+ hp is too much to leave on the table for a "look" in my opinion. I don't think an intake alone is going to give you 120 hp, but like I said before, it's the largest chunk.
 
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Discussion Starter · #203 · (Edited)
Thank you for the reply.
One more question, please:
How do you have the PCV hose routed? As in one hose to the throat of the upper, or the big T on the plenum and going to the throat, etc.
If you would like Vacuum #s let me know I have a gauge.

Its going directly to the upper on the big hose. The one right beside the Big T. I did run the hose a little long and high so the oil would have to travel up gravity further.

See Pic (Thought Cam numbers maybe helpful also)
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Auto part Pipe Fuel line Automotive fuel system Exhaust manifold

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Discussion Starter · #204 ·
I understand what you're saying, but his cam really isn't "big" - it's 240/248 ~.570 lift on a 112. Mine is 228/242 .600 lift on a 116 - yours, if I recall, is similar to mine. 12 degrees of duration isn't insignificant, but it's not much (we don't know the ramp speed, but it's still a logical comparison). 12 degrees isn't going to get you 50hp, much less the 150+ you need. Also, you can't compare his numbers below about 6,000 rpm. Remember, he's running an unlocked auto - the converter's not even coupled yet. That first hump is where the converter hits flash stall, the dip after is the recovery, and then by about 6,000 rpm, the converter's actually started to couple - but even if it's "tight" it's still slipping at least 8-10% in all likelihood; if not more. I see around 12% slippage at peak power in my car. To do an apples to apples comparison, you have to add AT LEAST 10% more power to Dean's graph to match your tranny. He's making at least 575 flywheel horsepower. You're making around 420 flywheel hp (I'm not using your dyno info because, quite frankly, it's bullshit). I make around 480 flywheel hp (that's with the shorties - I put the Kook longtubes in last night - I'd 500 would be a fair, conservative number for me now). Anyway, he's an easy 155 hp up on you. I've been guessing up until now, but now I just ran the numbers. Even if we're very generous and give his cam a 50hp "value," he's still over 100 hp up on you if discount the cam differences - and I think it's more like 120-130. There's also the fact that his pulls are SAE, and yours are unknown. Comparing an SAE graph to your dyno graph is grossly inaccurate (the errors compound in your favor, which is why you want to believe those numbers; I'm going to stop asking about your correction factor since you won't answer that question and I've asked several times). As I've said before, the track doesn't lie. He's got 16 mph on you. Using the 10hp/mph "rule of thumb" (though in this range it's more like 12hp), he's 160 hp up on you. Either way, you're leaving A LOT on the table.

There's another way to confirm these numbers. What's your injector size and duty cycle? We can easily (and quite accurately) figure it out from that too.

FWIW, I run solid mounts too, and they smoothed things out for me as well. My car idles so nicely I don't even run an IAC of any sort. I take care of it with my ignition tables (your tables do the same thing). See my tables above for reference.

Bottom line - the track doesn't lie and you're still leaving a ton of hp on the table. Leave the cam alone and put a good intake on it. You've got an excellent longblock and you've topped it off with a Burger King crown. If you're hell bent on retaining that Cobra look, then that's fine. But 120+ hp is too much to leave on the table for a "look" in my opinion. I don't think an intake alone is going to give you 120 hp, but like I said before, it's the largest chunk.
The next step is exhaust for sure after the I will be 100% ready with everything ready for the intake to be swapped and see results. This will be down the road but it will happen and results will be posted. My shorties are bumping my steering shaft every now that then and it has to be changed to long tubes but just don't have funds for full exhaust right now.

But I have 42lb injectors and duty cycle is 50 at 4500rpms 12.7AFR, 56 at 5000rpms 13. AFR, 60 at 5500rpms 13. AFR, 61 at 6200rpms 13.4 AFR, 62 at 6500rpms 13.1 AFR (It stays good 13afr till 5800 max hp then goes up to 13.4 till 6300rpms then falls back off to 12.8afr at 6700rpms at 64.3 Duty cycles)
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Discussion Starter · #206 ·
Nope, I don't need the vacuum numbers.
I appreciate the pics and reply.
I know you said you didn't need it but if anyone else ask its post 178 on this thread. (My build)

 

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The next step is exhaust for sure after the I will be 100% ready with everything ready for the intake to be swapped and see results. This will be down the road but it will happen and results will be posted. My shorties are bumping my steering shaft every now that then and it has to be changed to long tubes but just don't have funds for full exhaust right now.

But I have 42lb injectors and duty cycle is 50 at 4500rpms 12.7AFR, 56 at 5000rpms 13. AFR, 60 at 5500rpms 13. AFR, 61 at 6200rpms 13.4 AFR, 62 at 6500rpms 13.1 AFR (It stays good 13afr till 5800 max hp then goes up to 13.4 till 6300rpms then falls back off to 12.8afr at 6700rpms at 64.3 Duty cycles)
View attachment 1058683
I appreciate you're not getting worked up about this. Thanks for that. I hear what you're saying - my shorties interfered with my J&W Ultrabell (I actually had to grind on the bell and flatten the tube where the collector on Prochamber met). Can I just say I HATE the SBF header bolt pattern? What a royal bitch. I'm curious to see what the longtubes on my car are worth over the old setup - 1 3/4" shorty headers to a 3" Prochamber to 3" mufflers and dumps. New exhaust is 1 3/4" Kooks headers, slip on collectors, 3" pipes to mufflers and dumps. I also dropped at least 50 lbs as a result because the Kooks mandated an aftermarket K member - I went UPR chrome moly - and the Prochamber weighed about a thousand pounds.

Anyway, BSFC is a really good way to figure out actual hp. A typical BSFC (brake specific fuel consumption) for a performance N/A engine is .45-.5 (that means .45-.5 pounds of fuel per hp). Really tweaked N/A race engines can get into the high .3 range; but we're talking 14:1 compression, race fuel and 9,000 rpm.

So let's look at your numbers:

At peak HP, your duty cycle is around .6. Your total potential fuel flow is 42lb x 8 = 336 lbs/hr. With a .6 duty cycle, your fuel flow at peak hp is 336 x .6 = 201.6 lbs/hr. With a decent BSFC, that gives you 201.6/.45 = 448 flywheel hp. If you're closer to a .5 BSFC, that gives you 201.6/.5 = 403 flywheel hp. Most likely you're somewhere between the two, giving us 420-430 flywheel hp. The Wallace calculator gives you 355 rwhp to run 112mph at 3,600 lbs. Take 420 flywheel hp x .85 (15% loss through your driveline - manuals are more efficient) and you get... wait for it...357rwhp. 2 hp off. Pretty damn close.

For comparison's sake, I run 80lb injectors and hit 80% duty cycle. 80x8=640 lbs/hour. 640 x .8 (duty cycle) = 512 lbs/hr. On a blower car like mine, BSFC tends to be worse than N/A (because you usually can't hit optimum timing and there's the blower drag on the engine); typically between .55-.6. Let's assume .6 BSFC because I'm an idiot (and cheap) and usually run pump gas, limiting my timing further. 512/.6 = 853 flywheel hp. Since I run a glide, taking the converter into account, there's about 24% driveline loss. 853x.76 = 648 rwhp. If you use Wallace's hp calculator, to run 140 mph at 3,500lbs you need 653 rwhp (ET isn't as accurate - that's more chassis setup and in my case insane low-end torque from the Whipple). 5 hp off. Also pretty damn close, I'd say. The math always works if you're honest with your inputs and take any out in left field variables into account.

BTW - here's the Wallace Calculator I've found to be very accurate for MPH to RWHP conversion: Wallace Racing HP Calculator For 1/4 Mile
 

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There's another way to confirm these numbers. What's your injector size and duty cycle? We can easily (and quite accurately) figure it out from that too.
YES, we worked with a customer who had an "dumb" ported extrude honed lower intake and he asked us if we could make more power. I thought we could, so we tried it with a virgin lower. See his feedback method below is the method you suggest. Some indicators are just undeniable........
 

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Discussion Starter · #210 ·
What mph would be expected to confirm or deny a true 390 to 400 rwhp at str8baller’s weight?
That run I made was with the stock air box (I made 376hp) with that calculator I need to run 115mph.

117mph would be 400hp
118mph would be 408hp
119mph would be 419hp
120mph would be 429hp
 

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How was the intake flowed? On or off the heads? I assume off the heads
 

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I never understood that way.
Doesn't make sense
 

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That run I made was with the stock air box (I made 376hp) with that calculator I need to run 115mph.

117mph would be 400hp
118mph would be 408hp
119mph would be 419hp
120mph would be 429hp
You're still assuming the CF on the pulls you did. I pulled a legit SAE 561 rwhp, but went 9.8's at 138 mph at 3,500lbs (on pump gas - the 140 came from running Q16). How is that possible? Mineshaft air. I gained 90hp from weather - air density and the ignition timing wasn't being pulled due to IAT (I start pulling timing under boost at 140 degree IATs). Which you can correct for when you know the weather correction factors. The duty cycle confirmed the Wallace-calculated power (I datalog every dyno pull and track run - the MS3x does it automatically to an SD card). With an unknown CF, the dyno data is useless except vs other pulls that same day, and to make sure your A/F is good. And 376rwhp is more like 114mph - so you're really not far off; maybe 20 hp high for the day vs your dyno run. But again, you need to know the weather conditions when you raced. This is the one I use: DA Calculator - Density Altitude Calculator - DragTimes.com It's ok, but not super-accurate (water grains affect my car a lot).
 

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So without me digging through here... I'm sure there is some.chit going on being such long thread.. what's the numbers difference. After all..I "assume" that's what this is about, respectfully.
Custom cam.?.off the shelf $2 cam?
 

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Discussion Starter · #216 ·
So without me digging through here... I'm sure there is some.chit going on being such long thread.. what's the numbers difference. After all..I "assume" that's what this is about, respectfully.
Custom cam.?.off the shelf $2 cam?
Post 1 information and post 19 dyno #s.
Custom cam card is above on post 203.
 

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Hey how is the clutch pedal feel with the twin disk set up?

Is it the mcleod rst clutch? Just wondering i hear a few people say its like a hydraulic clutch in terms of stiffness.
 

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Discussion Starter · #219 ·
Hey how is the clutch pedal feel with the twin disk set up?

Is it the mcleod rst clutch? Just wondering i hear a few people say its like a hydraulic clutch in terms of stiffness.
Its has almost no slip. So you have to add a little extra fuel to help.

As far as petal feel its great I have a jeep with a hydraulic clutch and its not that easy but its like 16yr old girl wouldn't have any problems easy.
Lets do 1-10 clutch feel
My stock 92 GT - 5
King cobra clutch - 6
Aftermarket stage 3 - 8
Twin disc - 3 (This also has MM clutch kit I do believe it helps very nice kit)
Hydraulic jeep - 2
I have had all but the aftermarket stage 3 in the last year.
 

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Discussion Starter · #220 ·
Hey how is the clutch pedal feel with the twin disk set up?

Is it the mcleod rst clutch? Just wondering i hear a few people say its like a hydraulic clutch in terms of stiffness.
Come up to Hattiesburg and you can try it out and see if you like it.
 
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