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Discussion Starter #261
I don’t have the datalogs from the dyno, but I’m pretty sure everything was fine out of PE. So my stoich numbers and sensor are working fine. I tested a fuel sample and it was ~e75. When combining 15 gallons of e75 and 3 gallons of e10, I get e64. The sensor was reading 65-67.

I got a stock fuel pressure sensor in yesterday and I’ve wired up a 5v supply and an output to my mpvi2 to log it. I’ve plumbed it off the fuel rail test port to compare front and rear fuel pressure. It’s too wet and cold here to go make a test hit to get data.
 

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Discussion Starter #262 (Edited)
I datalogged fuel pressure yesterday. I bought an extra fuel pressure sensor/connector/pins. I made a simple harness to give me 5V supply and an output to datalog with hp tuners. To calibrate it I keyed the car on to run the pump. With the engine off I had 60 psi in the rear and 3.x volts up front. I cracked loose my front gauge to slowly lower pressure in steps and record voltage vs pressure each time. That gave me a pretty good curve to build a transform from.


With the car cruising, I had 1-2psi less pressure up front vs. rear. At WOT I had 4-5psi less. So that's not the issue. I dug deeper into the tune and compared maf curves (since that's where this lean runaway happened on the dyno). My maf curve was one of the few things I really kept on top of at the track, so I'm confident it's good.

Turns out the maf curve for 93 vs what was in my car last year were drastically different. The "e85" tune maf curve was almost a spot on match for what I had last year. So, I think the problem was more with the 93 tune. The tuner said his dyno (inertia) would read different than a street pull. Since we went from 93 straight to e85, there were never any street pulls to verify 93 fueling under real load.

So, now I might going to be a bit rich on 93 at wot when I put that back in the tank, but I think I can deal with that easily.


Also, now that I put some mileage on the car, I've realized that the trans shifts so nice I don't want to mess with it yet. It's not dead, just inching toward needing a rebuild. I'm going to push it a little while and see if I can hold that off until July and August when I don't want to go to the track because of the heat.

New parts came in Friday. TRZ trailing Arms, toe links and spindle bushings. I think a pair of DSS axles would make a nice pairing. I'm going to stick with 17's for now becuase I've never had them not hook on a halfway decent track. This should just help free up some power that's lost in the sloppy stock suspension. I pulled some brakes from the junkyard a while back (JE5 base model) for a 15" conversion whenever the unstoppable urge to go faster gets me there.
 

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So I just read this thread. Below is your quote from the first post.

My goal is a dead reliable car that I can take the family on trips in, but still have fun at the track. I just want to go make laps and go fast with minimal stuff for once. I want it to appear as stock as possible and retain the quiet comfortable ride it has now within reason.


I think we may have very different definitions of "minimal stuff" LOL
 

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Discussion Starter #264
So I just read this thread. Below is your quote from the first post.

My goal is a dead reliable car that I can take the family on trips in, but still have fun at the track. I just want to go make laps and go fast with minimal stuff for once. I want it to appear as stock as possible and retain the quiet comfortable ride it has now within reason.


I think we may have very different definitions of "minimal stuff" LOL
You must have missed the part after that (below in bold). I ran 6's and mid 10's in the spring of 2017. I've driven it on 1500 mile trips a couple times. That satisfied my original goal, so I kept going. Now the goal is 9's. After that, the goal will be 5's in the 1/8th mile, then I'll probably be looking for 8's. The journey is more fun than the destination.

I finally found a car after looking for about a month. It's an 09 thunder grey sedan with 58k miles, auto, black recaro interior and bone stock. I bought it yesterday in VA right outside of Washington D.C. and drove it home. I was looking at newer cars with lower mileage, but this one came in under my <60k mile requirement at a great price so I jumped on it. It's had two previous owners and the first one always had it serviced at the dealer. The second owner put 6k miles on it and I think wanted to get out from under his loan. The first owner must have parallel parked a lot and used the wheels as curb feelers. He also drove behind a dump truck most of those 50k miles. I have some paint stuff to take care of and I'm undecided about what to do to fix the curb rash on the wheels.

Here is my plan:

Round 1 -
airaid with green filter
Weld big and little's with drag radials
c&r heat exchanger
varimax pump


Round 2-
LT1Z 2.5 cam
2.5/8.6
ID850's
ARH 1 7/8" catted headers

My goal is a dead reliable car that I can take the family on trips in, but still have fun at the track. I sold an 8 second car because it was no longer fun. I just want to go make laps and go fast with minimal stuff for once. I want it to appear as stock as possible and retain the quiet comfortable ride it has now within reason.


Here is what will really happen:
Ignore all plans.
Go for 8's
 

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Discussion Starter #265
I drove up to Beech Bend yesterday for a test and tune. The DA was good when the day started, but slowly got worse. My first pass was decent [email protected] (video), but when I got back to review the data, the fuel pressure dropped off after the 1-2 shift. I checked the aux pump controller over and all the electrical connections were tight. This never happened on 3rd gear street pulls or on the dyno.

On the next pass fuel pressure was fine. The timing was very low on the first two passes only 18 degrees with e62. I added some timing to the high octane table. The last pass had 24* of timing, but the fuel pump dropped out again after the 1-2 shift. I'm at a bit of a loss on that one, I'm hoping I didn't hurt anything because it saw ~.86-.88 lamda in 4th. It went a best for the day of [email protected] with ~850' DA and the worst 60' of the day. It's going to go 9's, but it's going to take better weather and some more tuning.





The line started aimed at the valve stem. This is after 3 passes. I used to think beadlocks were for posers, but it's impossible to keep a tire balanced with this much movement per trip to the track.
 

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Discussion Starter #266
I've been out to my local 1/8th mile a few times this spring, but the results haven't lived up to my expectations. My car just wouldn't 60' like I thought it should. It was going 1.50-1.54, but I thought it should be in the mid to low 1.4x. I tried things in the tune (timing, TM, fuel), launch technique, tire pressure etc. None of that worked. Someone else looked at one of my logs and thought the car built boost kinda slow. It would take nearly 1.4 seconds to go from 0 to 13-14 psi. So, I re-adjusted my bypass valve, added a griptec pulley and a dsx idler.

I went back out last night and it seems the boost problem is fixed. It makes 14 lbs. in .4-.6 seconds now. This was ~2000' DA. I'm pretty confident there is another .05-.1 second off the ET with some timing. Once I can get some decent weather, I think it can go 9's. FWIW, from my spreadsheet data, this 6.55 would be a ~10.13.
 

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Discussion Starter #267
More new bests in worse DA. I'm not sure what's going on with the 1/4 mph. I might be letting off early, the log shows a lot more mph. The 4565 is the weight on the last 10.16 pass.
 

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Discussion Starter #269
Some updates. I tuned on the car a little more and pulled a little weight out and got a new 1/8th mile best of [email protected] in 2500' DA. That should put me in the 10.0x range. I could wait until the fall when the DA gets better and go run a 9 second pass, or I could try to do it in the summer.

I sold my ported blower to a friend and bought one of Jokerz used Chaos 102 core return blowers and a NW102 boosted throttle body. The new blower came with a 2.55, so I'll be stepping back a hair on blower speed, but not much. I have to find a throttle body spacer as it hits the pulley.

If it won't run 9's now in any weather, I'll have to take a hard look in the mirror at the tuner.
 

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Discussion Starter #270
I'm not real big on going to the track this time of year. Something about sitting around in a fire jacket in the lanes when it's 90+ outside just doesn't' appeal to me. Might as well throw more parts at the car instead.

I added TRZ toe rods, trailing arms and spindle bushings along with some new DSS axles and a new DSS aluminum driveshaft which saves 7 lbs over my stock driveshaft. 31.3 vs 24.1
 

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Discussion Starter #271
I plan to run true street at LS fest this year. That requires 3 back to back passes without opening the hood or trunk to add ice to my tank. I have an ~8 gallon tank that would probably supply enough cool water to keep me out of the red zone on IAT's for 3 passes, but the last pass would be pushing it. In any temp higher than my ice water temp, the heat exchanger is working against the ice. I figured adding a 3 way valve and a Y in the cooling circuit would be a nice way to bypass the heat exchanger at the track. Once I found the right valve, it wasn't hard to build a bracket off the stock IC pump mount and plumb it all in.

The blue route is with it bypassed. The red route (missing a hose to the HX) is through my C&R heat exchanger. It's easy to get to the valve with the car on the ground.
 

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I broke the seal. Rear wheels and tires and airaid installed. I'm going to hook up HP tuners tomorrow and see what easy changes I can make that might benefit me at the track.
would you mind telling the dimensions of the wheels and tires you have?
 

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Discussion Starter #273
would you mind telling the dimensions of the wheels and tires you have?
From the picture in the post you quoted, 17x10 with 305/45/17
 

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Discussion Starter #274
Another new best last night [email protected] Once I get my 60' back down to my 1.44 best, that should be an easy 9. This is at full weight and I'm guessing 13-1500' DA. I've been trying to sprinkle in more launch timing, but the this track just can't take it on a street car night.



This was in the 3rd round of my local 1/8th tracks fastest street car "race". I gave the Hellcat everything I had and he barely beat me. He's running a 4.5L whipple and E. I can't be mad at myself for loosing with an .010 light and a best ET.

 

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That's one hell of a run MeanMike! That video is great. You just just took off!!
Congrats!

Sent from my SM-N960U using Tapatalk
 

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Discussion Starter #276
Another new best 60', ET and mph. Full weight 4580lbs. and 1100' DA.

I'm out of injector. I was seeing 105% DC at the top of 1st and 2nd. A/F is still good, so I'm not too worried about it, but I don't know what's going to happen if I get significantly better weather.
 

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Hi Mike. Hows reliability with the V, any issues since upgrading with any of the parts? Im curious how many stock block V's are running in the 9s.
 

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Discussion Starter #278
I’ve driven it ~9000 miles including two 1200 mile trips with this combo. I have 164 passes at the track. My car had 59k miles when I bought it and the motor looked to be in great shape when I did the heads/cam a few years ago. That said, it could come apart tomorrow. But at this point I would feel It’s done it’s job.

The tune is the most important part. I’m of the opinion that it should be done in person. There are plenty of members here with very similar combos to mine and they make similar or more power. But not everyone focuses on the track. If 9’s are your goal, it will take more than just HP. You’ll need a serious track tuning (engine and trans), traction and good weather.
 

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Discussion Starter #279
Still whittling away at it. The 6.34 is a new best. It shifted to 4th just before the traps so mph isn’t any better. I just need the second 1/8th mile of timing equipment to make the 9 second pass official.

Tonight was “co-pilot” night at the track so I took a friend for a pass and we went the 6.48. He hasn’t been in anything fast in a long time. He wasn’t ready for that. Next time we’re going 4 deep with helmets and fire jackets.
 

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Discussion Starter #280
9 second goal complete! I've been consumed by this goal for most of the year. I've made ~75 passes and tons tweaks this year. I've just about worn out a set of drag radials. I'm very glad to have this behind me and my car at home in the garage in one piece.

This was a one and done. It ran 9.84 first pass so I hung out with friends the rest of the day. I didn't even look at the datalog, didn't really care.

 

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