Airflow, Cams, and 6500RPM drop on Dyno
#21
There is a lot to be had from a stock head to a ported head. And from a 95 head to a 99 head.
I do not have good data on an identical chassis and going from a stock induction, head, and cam to a ported head, bigger cam, and better induction. I did do some testing with a ported 95 head with stock valve train and then updating to a ported 99 head with 1mm over valves. The cam, and induction were identical. The only difference is I did have an electric water pump when I installed the 99 head.
I went a 13.89 (not sure on mph, I think 96) with the 95 head, and this was after months and months of tuning and testing. I went a 13.38 at 99 mph with the 99 head on the very first night. That is a substantial improvement from one head to another.
I do not have good data on an identical chassis and going from a stock induction, head, and cam to a ported head, bigger cam, and better induction. I did do some testing with a ported 95 head with stock valve train and then updating to a ported 99 head with 1mm over valves. The cam, and induction were identical. The only difference is I did have an electric water pump when I installed the 99 head.
I went a 13.89 (not sure on mph, I think 96) with the 95 head, and this was after months and months of tuning and testing. I went a 13.38 at 99 mph with the 99 head on the very first night. That is a substantial improvement from one head to another.
#22
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So this shows the advantage of VVT, Cams, intake?
I know that if all areas are addressed (porting, cams, intake) then the engine will make more power but which area offer the best bang for the buck? Would intake and porting offer 90% of the gains? Or just a camshaft?
for example the red line for my VVT with Hydra is electronicly limited to 7450. My factory camshafts and valvetrain was limited to 7200 but if power is dropping off at 6500 then I am not even using all the RPM my valvetrain will allow, with that being said would a intake solve it or could it be cam profile.
I hope that with enough info provided about a dyno sheet we would be able to tell that one mod may or may not be worth the expense.
I know that if all areas are addressed (porting, cams, intake) then the engine will make more power but which area offer the best bang for the buck? Would intake and porting offer 90% of the gains? Or just a camshaft?
for example the red line for my VVT with Hydra is electronicly limited to 7450. My factory camshafts and valvetrain was limited to 7200 but if power is dropping off at 6500 then I am not even using all the RPM my valvetrain will allow, with that being said would a intake solve it or could it be cam profile.
I hope that with enough info provided about a dyno sheet we would be able to tell that one mod may or may not be worth the expense.
viperormiata has the IM now, hoping to see a dyno from him one day.
#23
Brain beat me to posing my own dyno chart. That was stock untouched engine and head with a custom intake manifold and obviously everything else in my sig. But the manifold made the biggest difference in the butt dyno department and as you can see made for a nice flat torque curve or as I like to call it plateau.I plan to rev it to 7500 next time. the operator was afraid of over revving it. We all know how off the tachs are in these things.
#24
i dont know how many times i need to say it, everything needs to work as a package, there no one miracle solution. no one big gain. better flowing head wont do anything with out bigger cams, and a stock mani is just blocking your bad *** head. and a good mani wont do **** without a bigger tb. i mean every mod will add something but the gains are marginal. and integral makes like 10 diffrent cam profiles for miata 1.8l heads. and they will custom make cams. they can do anything for you.
#26
i dont know how many times i need to say it, everything needs to work as a package, there no one miracle solution. no one big gain. better flowing head wont do anything with out bigger cams, and a stock mani is just blocking your bad *** head. and a good mani wont do **** without a bigger tb. i mean every mod will add something but the gains are marginal. and integral makes like 10 diffrent cam profiles for miata 1.8l heads. and they will custom make cams. they can do anything for you.
#30
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I agree, my point was that headwork isn't cost effective unless you are really trying to stretch every last pony. IMs are cost effective, 99/01 heads are cost effective. Cams give up too much on the low end, headwork is too expensive.
#31
i dont know how many times i need to say it, everything needs to work as a package, there no one miracle solution. no one big gain. better flowing head wont do anything with out bigger cams, and a stock mani is just blocking your bad *** head. and a good mani wont do **** without a bigger tb. i mean every mod will add something but the gains are marginal. and integral makes like 10 diffrent cam profiles for miata 1.8l heads. and they will custom make cams. they can do anything for you.
From the dynos posted it looks like your statement isn't accurate.
#35
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Ok he says both were the same timing map, both at 14.5psi, both tuned as he drove down to delaware (setups finished the night before). 300 is the old begi cast intake, 70mm mustang throttlebody, and larger injectors. 270 is a stock '99 intake with the butterflys not operating (whatever position they are when you disconnect the solenoid is where they were). He's in bed so I didn't want him to fetch the datalogs to see what the boost curves were, but my recollection was they were similar. I was there when he made both numbers and remember comparing the datalogs when he did the 300 and was like...holy ****.
#36
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for example the red line for my VVT with Hydra is electronicly limited to 7450. My factory camshafts and valvetrain was limited to 7200 but if power is dropping off at 6500 then I am not even using all the RPM my valvetrain will allow, with that being said would a intake solve it or could it be cam profile.
FWIW hopefully later today or tomorrow I'll post my ported VVT head, stock upper IM, no butterfly lower IM dyno cart. Let's see if I have the drop too.
#37
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CTDRFTNA is corect about puting to gether a set up corectly, the reason everyone is seeing suck big gains from an I'm is optimization, the math behind a forced induction mani and a natural one is compleatly different so putting any mani on that is better suted for FI will see gains all over, and you will see even more gains from a properly set up mani that is built for your application.
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