Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

What the heck are you racing where your doors dont open? Thats just a cockpit orientation test to know where all the controls are and how to shut down the car and get out of the car in a timely manner. You dont crawl out the window. Nobody keeps power on in event of a crash to let power windows come down.

And i'd like to see someone crawl out the window in a 25.5 car.

All those other parts are common sense items. Everyone running a performance car should already have bought sfi spec flexplates shields and balancers etc. and the requirements depend how fast you are trying to go.

But i agree its ridiculous for a street car. You knock guys like me for not having the safety stuff but then have the brass to admit you'd wouldnt do it either

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

No I'm not. I'm mentioning guys that have made 2 passes, and declare themselves experts.

I don't race points anymore. But when some 20 year old blows his entire paycheck on his car because he's living in mommy's basement and has no expenses, then acts like he's doing things that we didn't do 20 years ago I get a little annoyed. This site is becoming more of that, and the true racers don't even log on any more.


My point, which was obviously missed, was that Rob is building a street car that could be 9 second capable, he's not building a "9 second car". He wants a smooth idle, reliable, he wants to be able to take day trips without worrying about stuff.

Beyond that.. I forgot what we were even talking about.


-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Weird i dont see that in this forum at all. Practically no activity here. Alot of on goin threads from years ago but nothing new done. I dont see any of the 20 yr olds you describe either. Hmm i may have missed those posts. Very few are building anything and i dont see any race cars here. Every build thread here is a street driven vehicle. Registered stickered and logged miles and passes. Oh well

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

That is exactly what I am doing. I had the GTA on Route 278 on my way to New York about two weeks ago in stand still traffic, when I seen smoke coming from the engine bay. This is something that I dont want to deal with anymore, too much heat from the turbo, and too many potential oil problem areas. For racing turbo's have the edge, but this is a driver too, and it has to run normal with the ability to throw down a nine second pass when pushed. This is why I said that I would settle for a 135-mph trap speed if I don't see that 9.99 1/4 mile ET.

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Well as per the tracking the long tubes are in New Jersey, but nothing came as of yet. Will of course give it until seven o'clock tonight, if not, then more than likely they will be here tomorrow. Going to have to fab their y-pipe a little and give it a 4" outlet, because I already welded a 4" inlet into the muffler I am using. These aren't that bad of an install, need to pull the oil filter, oil pressure sensor, pull the valve covers, notch the transmission cross member a little, as well as the bell housing ear on the passenger side where the converter cover bolts to, but other than that, should be a breeze to install. If they come with smaller than 1 3/4" (advertised size) primaries they are going right back lol...

Attachment 318532

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

sorry, i forgot to add 1/8 mile, not 1/4. lol.... he went 125 in the 1/8 with the d1sc on a 306 at 3600lb.

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

You are like me, just not quite as bitchy :)

Personally, I'd be driving your Vette daily if I was you. Don't get me wrong, I dig thirdgen's but not for a daily driver.

You saw my posts on these right? I used a flowmaster Y-pipe and re-worked the pipes a little. I also made a custom crossmember, I didn't like the whole drooping down under the crossmember thing.


https://cimg9.ibsrv.net/gimg/www.thi...ae9fb401b5.jpg



-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

It made 1100 rear wheel horsepower?

Tim races at Dorchester, and it is a 1/8 mi track. That just seems awfully fast for a 3600lb car. You would think it would be a featured car by Procharger.



-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

I knew you were running long tubes, but I forgot you were running these. Still can't get over the price being shipped to the door. That picture helps out big time. Overall how do you like them, how much rasp are you hearing, honestly?

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

there is faster ones than him.... this car has a d1 also, and is the (old style non-self contained).
1.teen 60's. 3384lb on some passes, and others he was 100lb heavier.


http://www.creperformance.com/bradschehr.html

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Took this video a few minutes ago, but it's hard to tell on the video with all the echo in the shop and alternator noise. (which is pissing me off as the alternator is about a week old).


I also seem to have a skip all of a sudden. wtf. This car doesn't wanna leave the garage.

-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

That's Brad's car that I cited in post #88, with the exact same specs as linked above.. ?? I must be missing something ??

-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Dang, it is. I dunno, but the link showing his time slips may be dated? Says his best 60' is a 1.3x, but he has been 1.14 and 5.20s or so in the 1/8

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

125 in 1/8 at 3600 is no where near 1100 whp. 1100 whp cars go mid 130's. I was goin 125's at 3750 with near 1000 whp tune ups. I think it was, maybe mid lower 900's. Have to go back and look at slips. 1200+ put me 3750 lbs into the 135-136 range.

At 3330 lbs or so thats alot less power. Still great for a D1 tho. Impressive. 800+ whp out of the smaller cubes is done often

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Yeah that is Brad when he was running the D1, now he has an F series...

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Okay, between Turbo Lou just pulling up to say what's up and showing me his ZR1 w/automatic (I wish I took a video, that thing is sick, and I mean sick, sounds unfreaking real), and with Joe throwing up a video, I cannot wait to get the exhaust done. Joe I'm going to cut the y-pipe that comes with the kit and create a 4" orifice, then run a 4" intermediate to the Flowmaster that I put a 4" inlet onto, then leading to dual 3" tips. Was going to ask Joe how he routed the plug wires, but the video confirmed it, thanks man. I had mine tucked under the turbo headers, but now I will run them overhead...

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Edit- my phone is getting the best of me.

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Keep in mind, the collectors are 3" and then neck down to 2.5. If you want to run them into a 4" you probably want to cut the 2.5" part off and do 3" around the trans.

The 4" pipe is 12.57" area, two 2.5" pipes are 9.82" together. Two 3" pipes are 14.14" total.

Wow.. Now that I think about it, I really should ditch the 3" catback huh?

Anyhow, fixed the screaming alternator. Went with a shorter belt and the noise went away.. I've never heard an alternator make internal noise from a loose belt.

I've been chasing an electrical problem down for half the day. Finally found it. I'm going to eat crow for this, but I think I found a bug in the MS module. For some stupid reason voltage is leaking from Spareadc1 to Spareadc2. Wtf. Back to it tomorrow.

-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Dunno if it's worth it to do the 4" now that I am looking at it, it would be a 4" spanning from the center of the drive shaft, up over the axle, then into the muffler, four to five feet the most. I already have the 3" tubing to finish it today too from the original catback, would just need to make an adapter into the muffler inlet. I really want to hear this thing. Regarding the Megasquirt issue, I only bust your chops about the MS Joe, should be an easy fix...

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Street,
What is the trans build up in the car? It is pretty good to with stand wearing out 3 turbos with hard driving. How many miles on each of the turbos? I have a few turbos from trucks with over 300K miles on them that hauled a lot so mostly in 25+ PSI of boost. Using hard line with short flexible couplers will alleviate the turbo oil leaks.

Did the turbo build get to the 135 mph goal? What is the goal with the supercharger?

Sure it is a ground problem or is an ADC read problem? Since there is only one A/D with a mux on the input then the SW must allow for hold/charge time of the cap. If the channels are adjacent numerically and the SW doesn't allow for sample and hold/charge time then it would appear to leak across channels. I would look at the code first. All A/D channels share the same analog ground at the device level.

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

I spent hours on this yesterday.

I found a sensor ground that was shorted to the block, which I thought was the culprit. It wasn't.

The ADC's float, which is normal, but what isn't is that if one of them isn't grounded (say you unplug something), that ADC will report the voltage of any of the others. So say I unplugged my MAF, the ESC module which is in another ADC would show 5 volts on the MAF ADC. This confused the crap out of me for a while.

Once I verified my wiring, and came to the conclusion that I have to ground sensors not in use, things went better. I still can't get it to do anything other than idle on the MAF. It's like the MAF doesn't see any airflow changes, but if I use my compressed air gun it reads that.. go figure. Runs great on MAP.

-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

It's a design problem as far as i'm concerned. I expect an ADC to float when unplugged, I do NOT expect another ADC to see the voltage from an unplugged one. This was screwing my day. The software just reads ad counts, so it's probably a hardware flaw (undocumented feature lol)

I don't know if the Delco stuff behaves the same way. In this case, I was using one ADC for my esc module, and another for the MAF. When I was unplugging the MAF I was getting 5 volts because the ESC module was high (normal).

The car runs fine on MAP, I just really wanted to get it running on MAF. I think I'm gonna configure TS to read the MAF gauge while running on MAP today and try to figure out why it's not reading airflow. The ONLY way I can get the MAF to put out more than like 1 volt is using my air gun spraying into the tube. Something is obviously pooched about the sensor itself or it's location. The wiring is spot on, I can apply +5 with a pot direct to the MAF connector and verify ECU response.


-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Junk, first two were ebay turbo's that gave constant problems, still have them and was juggling them back and forth between thrust bearings. First time I believe it was due to the return line not being large enough, and that was because I originally used a coolant fitting welded to the fuel pump block off plate. Cut that one off, welded a larger fitting in, then added a BOV as well thinking the return pressure was too great. Again, this build initially replicated a GN build, using no BOV. Same thing happened with the second turbo; 360* bearing collar wore out no longer reached in between the bearing, then the thrust bearing eventually went again itself...

Third time using a name brand turbo the shaft went, could pull the shaft by the compressor wheel 1/4" outward, blades ruined. Running it hard meaning 19* of total timing between 12psi & 15psi on the street. Anyways I am done with turbo's for the time being, wanna play with superchargers. The setup did well for what it is. I'm reusing the wastegate for the supercharger, but rather than buy another flange to be tig welded to the intake tubing, planning on substituting a 6" aluminum tube with a 6" stainless steel tube and welding a spare wasetgate flange that I have. Wish there was a way to muffle the sound, though...

Might use this for a possible Monte SS project down the line, once coated...

Attachment 318499

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Any floating input will read a random value within the input range. Normally a design will bias the input so that a floating input will read a deterministic value.

If you look at a GM schematic you will see the input is biased high or low so if a device is disconnected, the A/D will read a deterministic value. It will stay "stuck" and a fault can be reported.

Applying this to the MS module, you will see that spareADC is biased to ground so if no sensor is connected the MS will read 0 volts. Notice that spare2ADC is floating so it will read a random value with no sensor connected. This is why you are reading random values. I would have biased it to ground like done on spareADC. Note that MAT, MAP, CLT also suffer from this problem.

So if the MAP wire breaks.........who knows what the MS will read for a value and may think all is fine for a while. I wouldn't call this good design practice.

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Supercharger, turbo, nitrous.......all good. I hope the supercharger works out.

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Okay, just wrapped up the muffler end of the exhaust, the Flowmaster still has some life left in her. Here is a before and after below, I cut off the stock 3" clamps and welded the dual 3" pipes in, put back a 3" inlet into it, cut the original bracket arm that was welded to the intermediate pipe end entering the muffler, fabbed it a little, then welded it to the 3" passenger pipe. Polished the shortened exhaust ends, and hit it with 2000 degree black exhaust paint. Time to connect it all together...;

Before...

Attachment 318495

After...

Attachment 318496

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

I would not use that muffler lol

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Looks good! Aslong as theres no broken baffles i dont see why not

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

F1 blower thru a 80 series?

Has anyone seen a chambered muffler vs a high hp engine backfire?

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Doesn't matter which muffler with an electric cutout lol.

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

You still don't get it, I am running a larger supercharger to bring boost in earlier, albeit metered by the wastegate. The F1A will provide the same amount of boost pressure as the D1SC, just earlier and more efficiently. This engine won't last one run with the amount of horsepower you are speculating, this is a street car. The exhaust will be vented way before it reaches the muffler anyway with the cutout when it sees high boost pressure, so the type of muffler is irrelevant...

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

In that case you are ok, just use it whenever you go wot, else you'll be down on power. Those arent good enough for 9 sec power

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Oh i get it. How you make the power is irrelevent. What matters is if you expected to use the muffler for wot. The cutout was not mentioned anywhere unless i missed it.

A blower car needs to get exhaust out as best it can. On a turbo, preturbo can be smaller but post turbo its same concept. Theres alot of evhaust gas to get out. You know this

Cutout will save you, but as above, run it at wot or it will be restrictive

And what you mean it wont last with the power i am speculating? The thread says 9 sec. You mentioned 135 mph. I have been there and know what power it takes to get these cars there. Thats why you went with the F1a

If you dont think it will last then change the thread title and then i must ask why the F1a once again lol

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

I can only imagine, When i two step, mine shoots a 2 foot flame easy. LOL

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

We rarely see supercharged cars running a 2-step at the track Dan. Pretty cool.

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

I figure if it helps me launch the damn thing why not. It only cost me a extra $20 to have it installed when the MS2 was built.
The Red Dragon indeed breathes fire! (Through a flowmaster at that) If i had to guess im probably only 450 @ the crank (For now)
Attachment 318494
:lol:

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

i need to take a picture of my car at night like that , it lookks badass with flames clike that comming out behind each front tire , since my downpipes are much much shorter the flames are much bigger. i always thinkj im going to burn the paint off the side of the car , i think i need to add 2 inches or so to each downpipe, but i really dont want them sticking out the side of the car

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

He's running a manual transmission.

-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Gonna look into that some more to see the benefits.

On a side note, I completely forgot that Traviz ran an F1A with his street 383 Iroc, though it appears he ran the non-TPI bracketry forcing him to cut a hole in the hood for clearance. Talk about an exhaust restriction though, although I am sure that was just temporary and later changed...

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

He's not using it to spool, but to maintain launch RPM.

I used to race with a manual too when my left leg still worked.


-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

One of the many reasons why I'm going supercharger Dave. I only have one side of the header setup installed, driver side still pending, but I already see I made the right decision. So much more room in the engine bay, and its nice to see a full exhaust w/long-tubes, just want to hear it soon lol. BTW, does that muffler look familiar? You helped me pull it off of a Z28 after Warren flipped it over lol...

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Ahhh, now I see what you mean. Was going to experiment with a line lock connected to the hydraulic clutch once upon a time for that very reason, but then sold the car. Hey if it helps launching consistently then that is all that matters... :thumbsup:

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

That was the boat I was in too. Even with the single turbo, the engine bay was a disaster. And everything was hot.

-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

yeah, Trying to find the sweet spot, Its set at 2600 now but i think i need lower, still boils the rear tire. I should probably do a datalog and see what its building for boost

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

I ran two seasons with slicks, 26-8.5's. I used a 6 puck ceramic clutch, an sfi flywheel, and a modified pressure plate (ram).

I'd launch at 3500. Car pulled 1.60 60 foots which I thought wasn't bad for what it was.

The next few seasons I ran drag radials with a low RPM launch.

Msd 2 step and linelock hooked to a switch.

If I do track my firebird I'll probably try launching off the linelock. 2800 stall converter. I could wire the linelock switch to the megasquirt and use an input as a 2 step control, but I don't think it's necessary with an auto. Plus I'd be just racing test & tune not for points.

-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

I think having stock sized tires is my issue. lol. I need a set of drag radials to say the least

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

You run at new england dragway ?

-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

Looking at the schematic they are all actually a little different.


The random values make sense to me. Why voltage on SpareADC is showing up on SpareADC2 doesn't.

Looking at the schematic, if SpareADC2 is unplugged and you apply +5 to spareadc, it's going over the 1m resistor to the ground on C40 and showing on spareadc2 on the CPU side.

I don't get why they designed Spareadc2 this way.


This could be a problem if using analogue inputs if they are not grounded when off.

-- Joe

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

I will explain it another way.

1) SW sets the A/D mux to read spareADC that is connected to something sitting at 2.0 volts.
2) Next SW sets the mux to read spareADC2 this is floating (connected to nothing). The sample and hold cap was just charged to 2.0 volts from previous read. SW will read approx the same value now. Therefore, it appears that you have "leaking" when in fact you have a floating spareADC2 input that should have been biased to a known voltage.

Note that the 1 megaohm on spareADC is not that good of a choice either since the RC time constant with the sample and hold capacitor is a loooooooooonnnnnnnngggggg time.

Re: Chronicles of a 9 Second Trans Am... Final Chapter
 

It is a run time problem too. If A/D inputs float then they will "track" the previous A/D read value because of the sample and hold capacitor. It all depends on the size of the sample capacitor and the input load resistor (floating input is infinity load resistor and therefore no voltage change).

Suppose MAP on ADC1 and IAT on ADC2.
Suppose broken wire on IAT.
SW will read value for MAP, then read value on IAT but it will be the left over value read from MAP sitting on the input sample and hold capacitor. ECM will think the IAT is good but it is just really using the MAP voltage thinking it is IAT voltage.

The hardware should have inputs biased..............or SW should read a know value between sensor reads. It would go like this, read A/D for MAP sensor, read A/D ref voltage, read A/D IAT, read A/D ref voltage, and on an on.
Hey, maybe the MS SW people will read what I just wrote and fix their code. Oh wait, their code is copyrighted.