This is great. So basically you will be doing a back to back comparison of the 2g head/intake vs. the 1g head/intake. You actually are putting on a head that shrowds the valves more (4g67 head). Granted the CR is higher. But that doesnt affect flow. The difference in the hertz number (volume flow) is what will be interesting.
The most resent maf count before was 778hrz tunned. With a can tune now I am at 865hrz already & at 400rpms higher.
Advertisement
To browse the forums without the advertisements above, Login/Register
MAn I wish you had kept the 1g TB on for the sake of the experiment between the different generation head/mani combos . But regardless that's exactly the gain you were looking for right?
At the point where hertz was highest on the 2g head/intake, what is the hertz count? Did the 2g head/intake show higher hertz count anywhere in the rev range over this combination?
____________________________
Matt
dd '90 GST, Holset H1C
MAn I wish you had kept the 1g TB on for the sake of the experiment between the different generation head/mani combos . But regardless that's exactly the gain you were looking for right?
At the point where hertz was highest on the 2g head/intake, what is the hertz count? Did the 2g head/intake show higher hertz count anywhere in the rev range over this combination?
I still can bolt the n/t tb back on if I want to.
The 2g head & intake might have been better up to 4.5k but, it is hard to say how much because it is really close. I know it had more low end torque with the 2g head.
I did some pulls today with the wideband & it is real rich like 11.1ish and then slowly leans out as the rpms climb & then after 5800rpms it goes lean to 13.6.1 So it definitally makes alot more airflow in the 6k & up. I am going to tune to 13.1.1 a/f. Is that where these n/t cars are happy? Also what timing? I have it at 29* total right now. I usually tune v8's or turbo cars. And what would be the optimum shift points with this setup? I plan on leaving the line at 6.5k with 26" tall d/r's. Thanks
N/T timing map shows 20 degrees at 7K and full load. At 6.5K and full load 21 degrees. I'm sure there's some power to be had. The map looks a little conservative.
____________________________
Matt
dd '90 GST, Holset H1C
I just did some dataloggs today & I logged my highest 909hrz at 7156 rpms. I am not running the stock fuel & timming maps anymore. I am running 30* and 12.5 a/f right now. I think I am as good as the 89 oct will allow. I am going to put in some 91 oct & tune a little more.
I am mounting the 16" drag radials up now & I got the studder box set to 6k Getting it ready for this weekend. Timing is set & a/f is dialed in on 91 oct. I am thinking of putting in some 100 oct at the track. It is suppose to be cooler out so we will see what it does.
Cylinderwalls. And the crank. And the rings. The motor wouldn't even turn over with a breakerbar and no head attached. . . I pulled the pistons and after soakign them for now days, then rings still won't come out of the pistons. I knicked two of the crank journals trying to remove the pistons with the others stuck. . . had to remove some of the caps and try to move the crank that way to get to the other caps. . .
____________________________
Matt
dd '90 GST, Holset H1C
Have you been able to take it to the track yet? Im interested in seeing what you ran.
I went there yesterday afternoon & ran the following times in this order:
16.63 w/ a 2.492 60ft
16.56 w/ a 2.460 60ft
16.44 w/ a 2.465 60ft
16.42 w/ a 2.465 60ft
16.37 w/ a 2.451 60ft
16.32 w/ a 2.442 60ft
q/m trap was 85.62 mph
temp outside 52* and dropping.
Best with 2g head & intake was 16.92 w/ 2.51 60ft @ 82.17 mph
So I dropped .6 just by putting on the 4g67 head & 1g intake with 75mm tb.
Now this is not too bad for my elevation of 2130 da.
I launched at 4k studder box but, I think 6k would have been better because it hooked and bogged real bad off the line at 4k but, I didn't have a lab top with me. Also I checked the base timing today & it was at 2* so I was only running max timming of 22*. I will go back next year with this stuff fixed. I think in another hour I could have run a 15.9 in the cool air but, o-well. It was fun.
Thats not too bad of a drop on your times. I'm not tryin to thread jack but would I be able to get a good comp ratio if I used my 4g63 head with a 3-5 angle port and polish job? Anyways this thread had anwered a lot of questions I had bout the N/T.
Thats not too bad of a drop on your times. I'm not tryin to thread jack but would I be able to get a good comp ratio if I used my 4g63 head with a 3-5 angle port and polish job? Anyways this thread had anwered a lot of questions I had bout the N/T.
That won't change the compression. You would want to go with higher compression pistons or mill the head to raise the compression. An easy thing to do is simply swap the 4g67 head onto the g4cs 2.4 block & bam 11.5.1 comp 2.4 6 bolt. Even with a 4g63 head it would yield 11.0.1 comp.
It is in the turbo world too, until you get to the limit of the forces the reciprocating mass can tolerate. . . For 99.99999% of us including Kiggly, a bigger stroke makes more sense for a build where you want more power. Bigger cams are more tame. More power at lower boost. More flow than just revving to kingdom come, since a stroker flows 10% more air than a 2.0L at 9K. . . Much less cost is involved. . .
____________________________
Matt
dd '90 GST, Holset H1C
It is in the turbo world too, until you get to the limit of the forces the reciprocating mass can tolerate. . . For 99.99999% of us including Kiggly, a bigger stroke makes more sense for a build where you want more power. Bigger cams are more tame. More power at lower boost. More flow than just revving to kingdom come, since a stroker flows 10% more air than a 2.0L at 9K. . . Much less cost is involved. . .
Are you getting another 4g64 block or reviving your currect one?
. But regardless that's exactly the gain you were looking for right?
We had a bad storm. Blew off my improperly fastened engine covering and water rusted the block pretty badly. . .
