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Gunpilot 05-18-2015 07:30 PM

Yeah, the 1996 was first year OBD II, and PO used a GM race harness, so I'm adding a few runs for sensors to make inspection people happy. The tune will have all them deleted for performance, but inspection station won't know the difference. My 302 is a 1992 and been passing sniffer cleaner than a new car for past 2 years. Helps the engine was a new build and exhaust was all new with cats and mufflers. Looking forward to cleaning up interior and getting her on the road. Last test drive, water temps did not exceed 183, so looking good. Final HP numbers still not in, but I'll keep y'all posted.

Gunpilot 05-18-2015 07:36 PM

My other concern with the exhaust was the almost 90 degree turn of the dumps. Was not sure exhaust would actually dump when open. They told me the cats and muffler create resistance which will force air out of dumps when plates removed. Old find path of least resistance principle. I'm going crazy because still have not heard it. Lol!

Gator Bait 05-19-2015 06:23 AM

Don't forget to put the connector/brace back on the rear sub frame (under the cats).

Gunpilot 05-19-2015 08:57 AM

I have a set of V8 Flyin Miata sway bars to slap on. Having trouble trying to get the front one to fit and just asked FM for some pictures of orientation. When I was doing the SPEC Miata thing, most guys deleted that rear brace so I have never re-installed them on my cars. I was actually thinking of using those stock bolt holes to make a skid plate for the rear diff.

Gator Bait 05-19-2015 09:39 AM


Originally Posted by Gunpilot (Post 14973)
I was actually thinking of using those stock bolt holes to make a skid plate for the rear diff.

A skid plate would be even stiffer than a single bar across (I would think). The bar would prevent bottoming. Unless you are thinking of some off roading with it. :)

charchri4 05-19-2015 09:49 AM

2 Attachment(s)
The only thing about a skid plate is trapping the heat up there and I wouldn't go that route especially being so far south. If the cats really only need to be a visual you could make them hollow and that would cut the heat down quite a bit.

Just box the 4 holes together if you are concerned about stiffening that up back there. You can run arms up to your frame stiffeners too from the front ones. Excuse my ratty ass ford here...
Attachment 6362

Attachment 6363

BTW yes I did weigh it and the 1" box is 1.6 lbs per foot and the 3/4 is 1.1 lbs per foot so that whole mess all the way up to the engine cradle is about 25 lbs and to me worth it for how the chassis feels.

I had the same thoughts on your dumps and tried pretty much the same thing you are doing here on my 65 Shelby mustang clone back in the day. I ran hush thrush turbo mufflers right in front of the axle and I cut in at about an 75 degree angle in front of them to dump at the rear wheels like Shelby did. On a cold day when you could see the exhaust it dumped quite a bit at idle but heading down the entrance ramp there was more out the back than the sides. There just wasn't enough back pressure to offset the velocity of the air passing by the opening and most of it went straight into the muffler. However because it was dumping right into your left ear it was much louder!

BTW on a side note the same car sounded way better with out the X pipe than with. No X made it sound like it had far more cam and compression than it really did so of course I took the X back out the week after I put it in!

Gunpilot 05-20-2015 06:51 AM

All the wiring is done and everything checks out, except for a MAF check engine light. We hooked up to the PCM and it appears PO tuned this car with a speed density tune and it is failing the MAF. This combo will not pass OBD II emissions here in Houston, TX. This morning we are strapping it into the dyno and starting over with a detailed MAF tune that should clear it all up. I've done a lot of research on MAF vs SD tunes, and it is about a 50/50 out there. Most say the MAF should be tunable reliably up to 800HP. PO was planning on forced induction, and apparently a SD tune is the way to go for that.

Gator Bait 05-20-2015 10:34 AM


Originally Posted by Gunpilot (Post 14988)
Most say the MAF should be tunable reliably up to 800HP.

I asked about SD when I was getting my tune also and it was suggest by the shop to stay MAF. ...I wish I was have asked why... I know they do both...

charchri4 05-20-2015 02:41 PM

What code is it exactly? I get a 102 in mine once in a while (MAF low) and cleaning it seems to help. The oil you are suppose to use on the fancy air filters is not your friend for this code either...

Gunpilot 05-20-2015 03:19 PM

2 Attachment(s)
Just finished up. Kept final AFR nice about 12.1 at 6000 RPM. Probably could have pushed 13's, but not worth 8 or so HP to me. Final score is 382RWHP and 381 TQ. PO's SD tune was at 352.
Attachment 6356
Attachment 6357

Sunshine Guy 05-20-2015 10:39 PM

All that horsepower, and you still have 300+ ft/lb. below 2500 rpm. That's having your cake and eating it, too.

Gunpilot 05-21-2015 06:41 AM

That also what is causing me to loose traction! LOL

Gunpilot 05-23-2015 01:13 PM

Realized I was starting to blab about the build on my dyno post.

So with 402 to the wheels.......I want more. Don't know why as the tires tend to spin. Lol. Gonna complete the LS3 head and intake swap after the summer and I get a chance to enjoy it now.

I also scored a nice hardtop locally that I will slap on. Been thinking of paint scheme for this one, and I'm gonna keep it patriotic like my cammo wrapped 302. The base will be a flat black paint, and then use a dark grey vinyl to make Stars and Stripes down the sides. A large Apache helicopter on the hood, and a large star on the top. Going for the dark subdued look.

Gator Bait 05-23-2015 08:25 PM


Originally Posted by Gunpilot (Post 15061)
So with 402 to the wheels.......I want more.

hehehe...take another toke on the pipe.... Addicting, huh :naughty:

Gunpilot 05-23-2015 10:35 PM

1 Attachment(s)
Worked on the gauges a bit tonight. Used Glowshift gauges found on Amazon. They work really good. Their new series allows to set high and low parameters that activate lights built into the gauges. The tach also makes sounds. 10 different colors to set on each gauge. Best of all is you wire up one, and they daisy chain together with included wires. Easy peasy.
Attachment 6340

Gunpilot 05-24-2015 02:22 PM

Well, just went for a test drive to calibrate all the new gauges and inspect for leaks on the coolant sensor. Everything was good, and the I down shifted so I could listen to the open dumps. Then a BANG followed by the rear tires locking up and skidding to a stop. Strangely, I was able to put it in reverse and get out of the road, but anything forward is not working. All locked up. Leaning towards the rear end now. Clutch pedal feels good and tranny seems to shift through all the gears. Waiting for a tow now. I'll get it on stands at home for further evaluation. Engine still runs fantastic and dumps sound amazing.

Gunpilot 05-24-2015 02:30 PM

Even though having issues, here is video with dumps closed
http://i447.photobucket.com/albums/q...psumd7oxod.mp4

Gunpilot 05-24-2015 02:30 PM

And one with dumps open
http://i447.photobucket.com/albums/q...psexglf153.mp4

Gator Bait 05-24-2015 04:54 PM

Maybe they haven't finished processing, but when I click the links it says deleted by user.

Sorry to hear about the rear end. Hopefully it isn't too bad...

Gunpilot 05-24-2015 05:42 PM

1 Attachment(s)
Tow truck driver was an idiot. I asked for a wheel lift truck with dollies because my rear end was locked. They sent a flatbed. I actually went home and got my floor jack and wheel dollies so he could drag it up the ramp. Good thing this was insurance paying. Reloaded videos and links.
Attachment 6339

Gator Bait 05-24-2015 05:49 PM

aw man...I need dumps too! I need that hard top also. Give it up! lol

Gunpilot 05-24-2015 06:23 PM

I'm running a Getrag 3.73. What ratio getrag is best for this car since it looks like I'll be shopping for one.

Gator Bait 05-24-2015 09:53 PM


Originally Posted by Gunpilot (Post 15075)
I'm running a Getrag 3.73. What ratio getrag is best for this car since it looks like I'll be shopping for one.

Mine is a Getrag 3.42 I think it's decent for the T56 and LS3 combo. I don't really feel 6th is usable until 60+ though, and I can get some cam surge at really low parking garage speeds at times. ...maybe your 3.73 is 'best'.... It's slicing hairs between the two though...couple hundred rpm maybe.

Gunpilot 05-25-2015 09:51 AM

I have a bead on a 2011 CTS differential for $100. Down side is that it is from an automatic car. Gear ratio is 3:23 and I have read that that is a fairly streetable gear. It would be and easy cheap fix until I can possibly get a custom built up diff. I believe the only difference in a manual and automatic differential is the gear ratio.

Gator Bait 05-25-2015 09:55 AM

For $100 and some fresh gear oil, that's hard to beat.


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