Place your bets, what will it run

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Toluene56

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It's that time of year. First test n tune locally is apr 9.
I made some changes to the car. What do you guys think it will run?

Previous setup ran [email protected] naturally aspirated at 6800ish DA and 10.62@127 letting off about a hundred foot before the beams, with "100" jets on an NX gemini nitrous plate (7400ftDa).

This year. Same engine:
5.9mag block 408ci
Scat crank and rods
Icon forged pistons (grand canyon gap)
11.67:1 comp
Trickflow heads, super vic intake (port matched)
Howard's solid roller 257/267@050 .640/.645 @108 ( not meant for boost, but still feels spunky).
E85 850 HPI blow through Carb
Tti 1 7/8 headers 3.5" exhaust to axle
Torqstorm supercharger about 7psi at wot.
Converter flashes about 5k
4.30 gear, 904 rmvb standard gear set
28x9 pro bracket radials and some cal tracs

20220308_172340.jpg
20220308_195526.jpg
 
My initial thought is......
“Too much gear”

What’s the boost right at the hit?
I agree.. I also have another 3.55 chunk with a spool I can use. I was gonna try the 4.30 first. Just to see how it goes.
It only makes about 2psi at say 3000rpm, reads about 4psi at 4500. Might be a little off as I'm trying to control it when it goes. But at wot 5500 to 7000 it shows 6-7.5psi.
 
If it hooks and runs clean out the back, my guess will be 10.20s on low boost. Turn that thing up already!
 
If it hooks and runs clean out the back, my guess will be 10.20s on low boost. Turn that thing up already!
I was thinking 10.20-10.40 128+ . Sea level I'm sure I'd get booted from the track.
This blower is limited. They do take a procharger style pulley so I can buy a smaller one. But it overspins it by a fair amount. It currently has a 3.25 pulley, not sure if a 2.95 pulley would gain a significant amount.
 
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This blower is limited. They do take a procharger style pulley so I can buy a smaller one. But it overspins it by a fair amount. It currently has a 3.25 pulley, not sure if a 2.95 pulley would gain a significant amount.
I’m not sure it would do a lot honestly. Except heat up the air more. I’ve seen guys try to get more out of the torquestorms and they seem to be in their happy zone in the 5-7 psi range.
 
I’m not sure it would do a lot honestly. Except heat up the air more. I’ve seen guys try to get more out of the torquestorms and they seem to be in their happy zone in the 5-7 psi range.
Exactly. They're flow limited. I might just get the 3.1 pulley that torqstorm offers. 1psi more is better than none right?
 
How does it feel compared to the 100 shot?
I used a progressive controller to launch. So the 100 shot felt almost like it was na, very smooth.
This feels like there's a bit more.
 
I was thinking 10.20-10.40 128+ . Sea level I'm sure I'd get booted from the track.
This blower is limited. They do take a procharger style pulley so I can buy a smaller one. But it overspins it by a fair amount. It currently has a 3.25 pulley, not sure if a 2.95 pulley would gain a significant amount.


Why would you get booted from the track.
 
Awww my 1/8th mile sucks.
Screenshot_20220320-154910_dragy.jpg

Lol. I'm joking. This thing is gonna rip pretty good. Dragys are friggen awesome.
 
Probably has more in the suspensioAt an Ihra track you can run 6.00 with a car like your usually
Fresh slicks are crucial Aren’t 904 s great
 
Considering that the engine NA looks like it would be good for mid-low 10's (sea level), I would bet with a decent launch you will be in the high 9's. Boost is boost...it makes the high vs low altitude thing less of a factor compared to NA.
 
Whatever it runs will be traction limited.
 
Considering that the engine NA looks like it would be good for mid-low 10's (sea level), I would bet with a decent launch you will be in the high 9's. Boost is boost...it makes the high vs low altitude thing less of a factor compared to NA.
Armchair racing using some wallace calculators, I figured around 9.8-10.2@135ish. I'm leaning towards the 10.2+ range. Couple more weeks and I'll see how it likes the 4.30s. Or I swap to the 3.55s and see how it likes that, probably safer.
 
Well... I got to test and tune... got the carb mostly sorted out. Couple more tweaks and it should be pretty nice. Swapped the 4.30 gears out for 3.55s. Just so I wouldn't spin the crap out of the engine.
4,000ft base elevation - 4994ft DA @ 62°f
First run 11.63@121 (2.05 60ft)- according to spectators it was roasting the 28x9 pro bracket radials for the first 100ft. Along with the obvious fueling issues (lots of stuttering) not that great.
2nd run Changed jets from 78f 95r to 81f 95r also had to roll into the throttle
[email protected] much better. But still 1.87 60ft still stuttering/missing
3rd run , upped secondary to 98s (might as well see) it absolutely hated it.
11.48@119 1.76 60ft
4th run - changed jets 85f 95r double checked float Levels and fuel pressure.
11.008@125 1.76 60ft much better.. still rolling into the throttle, I want clean fueling before I mess with suspension.
5th run - all the same settings, just checked tire pressure and returned it to 17psi. Rolled into the throttle just a little faster. A very slight hesitation at 6000rp, few more fueling tweaks and it should be good enough to start on suspension tuning.
[email protected]
20220409_182447.jpg

Screenshot_20220409-184541_dragy.jpg
 
Are you watching o2, or just jetting by track results?
E85 right?

Pretty close to the 100 shot, but that was with a much higher DA.
 
Are you watching o2, or just jetting by track results?
E85 right?

Pretty close to the 100 shot, but that was with a much higher DA.
Watching afr and checking plugs for damage and timing marks. E85 burns pretty clean. I was using track results but mostly just mph. The goal was to get the wot stutter eliminated.

Wot looked like .78ish, trying to watch oil pressure at the same time. From what I've read and been told .71-.75 is an e85 happy spot, but really whatever the engine is happy with.

I was driving it like I was leaving a stop light and Rolling into the throttle I was surprised it even had a 1.7 60ft. It felt so effortless. And with the 3.55 gears makes it pretty sweet. I bet 3.73 would be a nice happy gear.
 
Yeah, your 1/8 mile speed says you should be in the 6.6-6.5 range. Get that thing to launch and you will be in the 10.4's as is.
 
Yeah, your 1/8 mile speed says you should be in the 6.6-6.5 range. Get that thing to launch and you will be in the 10.4's as is.
I would be ok with that. It's still a touch lean and there could be some left in timing, but probably not.
The one attempt at a launch was footbrake at about 3500rpm. Pretty sure it topped out the shocks. So I'll need to work on that.
This picture shows how much the entire car "hopped" then blew the tires of violently, but it tried to hook. So hopeful.
FB_IMG_1649645029089.jpg

Here's before launch for reference.
FB_IMG_1649646533493.jpg
 
Try it off the foot at lots less rpm, like 2k, so your chassis is relaxed and it hits the converter harder.
May help stick it
 
What’s going on with the front end in the launch photo?

How much pressure are you running in the radials? Have you tried the Cal Tracs in the bottom hole?
 
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