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Btw the dyno graph for the long tubes only goes to 6k rpms and was still showing horepower gains. Have them rev it up to 6500 like they did on the dyno for the mid's
I noticed that as well, I can deal with +/- 5 hp (although its probably more SAE VS.STD). Its the huge tq. loss that's got me.
Dyno readings should always be taken with a grain of salt. Never go into a session expecting a number, the tuner will hate you, and you will always leave upset. A dyno is ment to be a tuning device, to make the car run safely at its full potential
My car ran a best of 11.67 @114 when it was auto. I swapped to a six speed and it put down the exact same numbers. It has since run a low 12 with the six speed and I've beaten cars with higher numbers.
All I wanted from the tuner was strong idle, my ac to work at idle and strong catch coming down to idle. (Ok I'm lying a little bit, I told him I wanted alot of torque and down low power since it's a daily)
Fast intake, long tubes, true duals, 232/230 595/595 114+1 cam and stock 806 heads
I disagree about track times being better than dyno numbers. They can be manipulated in a similar fashion to dyno numbers. Plus not everyone has access to a track anymore. I care more about dyno numbers and how the car drives on the street than some stupid track number. Best case with track numbers is trap speeds. ET means little to nothing.
^that is far more accurate. The better argument is seeing improvements and gains. If a dyno is "just a tool" like most say then you should take it for what it does, show gains between a and b.
Did you ever post up the cam specs and head flow numbers? I still think the valve events are all wrong for this setup and adding the better flowing headers only made the issue worse.
Did you ever post up the cam specs and head flow numbers? I still think the valve events are all wrong for this setup and adding the better flowing headers only made the issue worse.
Here is the cam card.
I never had the heads flow tested. The tuner said It was the highest hp car he has ever tuned with the hot cam. So I assume I did ok with the heads. Like I said I just took out the rocker stud lump and cleaned up the castings. I only polished the exhaust ports and just tried to smooth and blend the intakes. I did not alter the contour of the swirl ramps.
I disagree about track times being better than dyno numbers. They can be manipulated in a similar fashion to dyno numbers. Plus not everyone has access to a track anymore. I care more about dyno numbers and how the car drives on the street than some stupid track number. Best case with track numbers is trap speeds. ET means little to nothing.
Thats an opinion, and I see your point but still sorta disagree. See below.
Originally Posted by tech@WS6store
^that is far more accurate. The better argument is seeing improvements and gains. If a dyno is "just a tool" like most say then you should take it for what it does, show gains between a and b.
You must be new to cars, and racing. The whole issues with your theory and this retarded thread is something so useful like a dyno, can produce these incorrect results, and NOT compare A to B in a 100% factual sense.
Bottom line is, Ive driven cars with stock manifolds, and my own personal car has had Hedman 1 5/8 stepped to 1 3/4, 1 3/4 stainless, 1 7/8 Hooker, and now TSP 2" stainless. I have literally felt each and every change to throttle response and powerband of each header. The BEST all street driven header was the Hedman, and no one here wants to hear that. It produced velocity and excellent midrange scavenging. With a manual car or auto with stock converter this is wonderful. Once you mod either combo, overall flow of the bigger primary wins out in my opinion. I wouldnt trade back to the Hedmans for any amount of money, but when my car was a different application (and overall speed was the top priority), they fit the bill nice for throttle response and midrange power.
You make a very good point. How well anything works is totally dependent on the situation, and the particular combo of parts involved. ALSO on what is expected of said combo. Different strokes....
Insulting others isnt necessary. Track times can be manipulated by weight reduction, gears, converters, line locks...the list goes on. Even the weather that day can effect it. Hardly any of that would show on a dyno. You are saying a loss on the dyno of 20 ft lbs (and what appears to be all over a loss) and no gain in hp can equal a faster time at the track...then i do not believe you.
Dynos have weather stations and correction factors for those discrepancies. Drag strips you ran what you ran. Why do most people/shops take their cars to test them out at the coastal drag strips even if they are far away vs their local one? Maybe its to keep their conditions the same as well...but i believe the underlying factor is already known.
That other idea was indeed more factual because most guys that do dyno their cars or even just modify them do not go to the dragstrip and therefore couls not see the gains there. And if they did, how could they compare it to the dragstip across the country?
You do not have to agree with me, and it seems likely you wont, because you are on one side of the argument and choose to stay there.
If a car dynod low numbers for a combo when compared to others out there but ran better at the track than before then of course its a win. Then again if that car changed some things and lost power everywhere and ran a better time, there was something else involved.
Well the results are in! Here is an overlay converted to SAE on both runs. The Macs are in red and blue, and the SE LTs are in green and orange. I pick up tq and hp down low with the Macs but gain it up top with the LTs. All in all the Macs are a surprisingly good header. But I think I'm gonna put the LTs back on for the extra power up top. What would u do????
On another note I also had him do a pull with the cut out open on the TSP cat back. I gained 6 ft lbs and 8 hp with the cut out open. Here is the graph for that.
Cut out open with Macs.
As far as the 20 hp and tq loss in a year.... I have no clue. With the Macs it is also almost an identical pull with the same hp and tq values. I don't know the car feels just as strong as ever, I guess a trip to the track will show some more.
The orignal year old pull.
Last edited by dave04da; Apr 20, 2017 at 04:47 PM.
I expected more from long tubes honestly. Even cheap ones.
Granted its not some huge cam big cid build etc, but it should be more evident besides just above 5700. Ive seen gains before from pace setter to tsp or kooks etc staying in the 1 3/4 range everywhere. That was long tube to long tube even.
Id like to see alot more a-b comparisons like this. Well done OP.
That is what is expected. Makes much more sense now. Either the old numbers were a fluke or something odd is going on.
Yea, I tend to think the old numbers were a fluke as well. My buddy with a bigger and better performing cam pulled 382 tq and 394 hp on the same dyno last week with LTs and a 6 speed. Very similar cars in mods although he only has 16,000 miles and I'm at 85,000. So for a little hot cam I'm pretty happy.
I expected more from long tubes honestly. Even cheap ones.
Granted its not some huge cam big cid build etc, but it should be more evident besides just above 5700. Ive seen gains before from pace setter to tsp or kooks etc staying in the 1 3/4 range everywhere. That was long tube to long tube even.
Id like to see alot more a-b comparisons like this. Well done OP.
Yea, I tend to think the old numbers were a fluke as well. My buddy with a bigger and better performing cam pulled 382 tq and 394 hp on the same dyno last week with LTs and a 6 speed. Very similar cars in mods although he only has 16,000 miles and I'm at 85,000. So for a little hot cam I'm pretty happy.
Either way, I agree with WS6store, props for going back and getting the dyno time again with the midlengths instead of just bashing SE and leaving it open ended like most would have.
Looks like the Mac's are holding up well! Good job for sharing your results . I think my Mac cats were choking my exhaust flow. I wish I had an off road pipe on the dyno. Too many variables .
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