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Discussion Starter #1
Got a trip to Silver Dollar planned this weekend and I'm looking forward to trying out my new Vic Jr. intake. I've only driven the car a few times through the neighborhood with the new intake and it seems to run very strong.

I didn't change anything in the carb but I feel like there should be a need to rejet it. I'm sure air flow thru a Vic Jr. and a Stealth intake are very different which would yield a need to retune my 750 Holley. Should I fatten it up? Lean it out? Or am I just over thinking it? I want to say it has #73's in the primary and can't remember the last time I was in the secondary bowl. I presume maybe #78's or so?

Anyhow, with the cooler weather, I'm hoping to stay in the 12.80's and shooting to dip into the 12.70's and hit 110mph. PB now is a 12.88 @ 108 with the old setup so hopefully I'm not too far off.


Test N Tune is Friday night and after that I'll be heading up to Road Atlanta Saturday and Sunday. Reckon I can see what those guys use that steering wheel thing for ;)! I'll try and post some videos and time slips and share some road race pics!
 

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I think the trend is leaner with a single plane intake so I am not sure if you will need to rejet or not..I would listen carefully when you make a pass (for lean misfire)and check your plugs after the run.....Sounds like you need to start keeping a race journal so you can remember stuff like jetting or timing,launch techniques etc...Another trick is to stick a small piece of duct or masking tape on the top of each fuel bowl on your holley and write the jet numbers on the piece of tape.....BE CAREFUL turning corners! :D
 

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Discussion Starter #3
Thanks frdnut. I try and keep my setup in my head but with school cramming all kinds of new stuff in, that info seems to be finding its way out. That's not a bad idea though.

So you're saying I should bump the jet sizes down a bit?

This might sound like a noob question but how exactly do you read the plugs to see if they're fat or lean?

Also, I plan on uncorking the headers to make it breathe a little better.


...And don't worry, I'm not going to be the one doing all turning, just riding along.
 

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Discussion Starter #5
As promised, here are some videos from the weekend.


This was my second pass and new personal best! 12.63 @ 107.9!


My million dollar time slip!

Unfortunately, I wasnt able to tune at all. Honestly it really didn't feel like it needed it. I let my buddy drive the car and he made two passes.


At first, I thought he grenaded 1st but apparently, he said it came out of first? Never happened to me before.


His next pass, he was out of the groove and didn't do a good enough burnout and the car lurched toward the center of the track. Scared the living dog $h!t out of me!

The next pass, I hit second and heard a bang. The elcheapo tranny mount let go. No big deal but it put an end to the night.


Like I said, I also spent Saturday and Sunday morning at Road Atlanta. It was pretty busy between diagnosing a blown head gasket on my buddy's foxbody and running back and forth between the paddock and the track. Wasn't able to take any pics but we had a lot of fun. Coolest car at Road Atlanta was a dark red Daytona Coupe kit car that had a 408.
 

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Discussion Starter #8
Thanks guys! I really wanted to make more passes but I was held back by broken parts. Like they say, "If you're not breakin' ****, you're not trying!"

I am 100% sure that the Vic Jr. is what made the difference. Still without any tuning it pulled very strong. I had three good passes and it actually hung the LF hoop (as dennis would say ;) ) and carried it a bit! The cool weather always helps, I'd say it was in the low 50's or so and had rained the day before. Track prep was incredible. Every time I rolled up to the tree after a burnout, it sounded like someone was peeling up industrial strength duct tape :). That could be why the tranny mount let go.


Not the best quality video (camera man might have had a beer or 3) but I'm in the far lane. It let go when I hit second

I'm thinking about putting a 6200 chip in it now. When I crossed the stripe, it was bouncing off the 6000 chip. Maybe could have squeezed a 108 mph out if it wasn't. Just don't know if I want to spin it that high. Also considering re-ringing the bottom end. That is one thing that I have not touched since I've owned the car. Supposedly when I bought it in '06, it only had 5k miles on a rebuild. Don't know how reliable that is because I popped a head gasket 6 months after owning it. The motor only makes 125psi on a compression gauge and #4 only makes 95-100psi.



Good quality, up close shot but my buddy didn't record the launch! Ahhh I gotta train these guys!
 

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Wow it sounds like you need to freshen up that shortblock...I remember my first clean pass with my new 408..I was also running a 6000 rpm chip and was kinda startled when it started missing badly at about 1000ft or so..The 6 grand chip had worked just fine with the old 302 and 100 mph trap speeds..Not so much at 120+. :).....You will either have to go for the 6200 or bump up your tire diameter a bit..
 

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You might be suprprised how much et there can be jetting on a motor that seems to be happy. I found about .25 and 3 mph in mine.
 

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Discussion Starter #11
Right now I feel so far away from 120mph lol. It is getting to be time for new tires. They're 255/60/15 drag radials. I've run 28x10.5 slicks but it bogs real bad off the line. I like the way the smaller tire gets out of the hole.

You think a stock/tired bottom end is safe to spin to 6200?


You might be suprprised how much et there can be jetting on a motor that seems to be happy. I found about .25 and 3 mph in mine.
Oh believe me, I know what you mean. Being a broke college kid for the past 4 years, I've found plenty of ways to shave time with tuning rather than throwing piles of money at it. ;)
 

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Right now I feel so far away from 120mph lol. It is getting to be time for new tires. They're 255/60/15 drag radials. I've run 28x10.5 slicks but it bogs real bad off the line. I like the way the smaller tire gets out of the hole.
Those drag radials are going in the wrong direction. If you need a shorter tire, then get a 26" slick. MUCH better drag tire than a 255 drag radial!
 
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