itb na build questions????
08-01-2013, 10:44 AM
#63
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Yep, smaller bore makes it easier to control the flame front.
Look at sport bikes that run 13:1 on 91 with speed density systems, or the Coyote engine mustang's for instance that can run perfectly fine on 87 with 11:1 compression. There is only an 8hp difference between 87 and 91 according to Ford.
If E85 was more readily available in my area, when I build an N/A 1.8 next year, I'd be looking at 13:1+
Look at sport bikes that run 13:1 on 91 with speed density systems, or the Coyote engine mustang's for instance that can run perfectly fine on 87 with 11:1 compression. There is only an 8hp difference between 87 and 91 according to Ford.
If E85 was more readily available in my area, when I build an N/A 1.8 next year, I'd be looking at 13:1+
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08-01-2013, 11:44 AM
#65
Originally Posted by Full_Tilt_Boogie
What cams are you running?
What cams are you running?
valve lift is .370"/.370"
advertised duration is 237*/237*
duration @ .050 is 214*/214*
lobe center is 111*/111*
It is not a whole lot bigger than a 99 or later vvt cam.
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08-01-2013, 01:10 PM
#67
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I have 12:1 pistons in my car. At first I ran a blend of race and pump gas. After I got used to tuning it a while I took it down to pump gas. Never had a problem with det, and I visually inspected the pistons numerous times. Little motors are far more knock resistant than big motors. Take the advice from someone who has done it.
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08-01-2013, 02:34 PM
#68
Steve, you have to consider that I ran the motor like that for years without the water pump. The pump was on there for one hard night at the dragstrip, and maybe a five hundred miles on the road. I made a few hundred passes at the drag strip before the pump. The cam is just a tad bigger than stock, and it is a full point higher in compression than the 11:1 I recommended. So I still stand by my logic that 11:1 is childs play.
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08-02-2013, 03:35 AM
#69
ITB's, my .02
ITB's, I like 'em. Coming from the motorcycle industry where everything fast has them, they're fairly simple and straightforward.
So instead of forced induction, ITB's are used with a higher compression ratio, bigger cams and rpm's to make power. As such, an aftermarket ECU only makes sense. Also, put me in the camp who thinks that 10.5:1 compression on premium gas is no problem at all.
There's something inherently "right" about an inline 4 iron block with ITB's. it's like the better version of carbs. Make mine with a top mount shower/fogger.
So instead of forced induction, ITB's are used with a higher compression ratio, bigger cams and rpm's to make power. As such, an aftermarket ECU only makes sense. Also, put me in the camp who thinks that 10.5:1 compression on premium gas is no problem at all.
There's something inherently "right" about an inline 4 iron block with ITB's. it's like the better version of carbs. Make mine with a top mount shower/fogger.
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08-03-2013, 01:28 AM
#72
I've heard that about the TT manifold. If I had a complaint, it would be that the stuff is not exactly feather weight; It needs a few more passes under the mill. I understand that extra CNC time means more expense, but this stuff hangs off the engine far enough that I'd like to minimize the weight.
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