'98 Cobra Transformation!

[Turbo98]

Haha. A pretty major update I guess.

Well, I actually think the intake is set-up just right for the turbo upgrade. We shortened the runners and it didn’t give up anything on the low end but it extended the power up top a bit. At the higher boost levels, I observed the power starting to fall off up top. Since peak power was occurring earlier and earlier the more we turned it up, it indicated to me that the turbos were tapped out. So I believe the intake runners will be fine the way they are and won’t pose a restriction. I think with the larger turbos, it should be good for another 200-300rwhp at the same boost level without the intake choking the power. The runners are so uniform and unrestricted with no dog leg bends or anything that it should flow well. The high injector placement will also help sustain higher RPM power to redline, I firmly believe the old turbos were holding back the power mainly due to:

1. The relatively small turbine wheel/housing
2. The fact that the wastegate gas was being recirculated
3. The resultant high back pressure situation

When I selected the 58mm turbos, I didn’t think the engine would be as efficient as it is. It was kind of an unknown and there was very little information out there on this intake. The guy at Ford that designed it is retired. We kept making changes until I thought the combo would perform the way I wanted. Then the turbos ended up being the restriction which was the last component I thought would be too “small”. What will be interesting to see is how much mid-range power will still be there. I’ve studied it enough and now it’s time to just do it. We’ll see I guess!

 

[old yellow]

look forward to seeing the new upgrades

 

[Turbo98]

Some of the new hardware has arrived! Since I went with the larger .70 a/r compressor cover, the inlet increases from 3” to 4”. So I need new filters. Apparently these are a special custom filter made just for HP and since they are out of business, it poses a challenge finding them. They need to have a 20* angle on the flange in order to square them up so they tuck behind the bumper support. So I found a place that could make a couple custom ones. They turned out real nice and should work great.


Ported “S” compressor housing/Billet Wheel:


V-band outlet:


Precision’s new CEA “billet” turbine wheel:


I also had to get a couple of Precision’s 3” stainless v-band flanges and clamps for the downpipes in order to match the ones on the turbos. The wastegates and other misc. hardware has shipped so I’ll be receiving that soon. Then all I have to do is get the pipes fabbed up and install everything, lol.

 

[Murder Snake]

wow, that looks really impressive. this just keeps getting better and better!! Nice job as always!!! :bowdown::bowdown::bowdown::rockon:

 

[Turbo98]

Thanks man. It's just taking a while to get this stuff done.

 

[Turbo98]

Nothing big but I received the rest of the hardware in to complete the turbo swap. I have two of the wastegate assemblies, inlet SS v-band, outlet SS v-band, and fittings. Each wastegate came with 6 different springs which is nice:

 

[Murder Snake]

Nice!!!!

 

[Turbo98]

Well, I’ve had a few snags that I’ve had to deal with. So it kind of put me behind schedule.

First off, long story but there was a mishap with the tailshaft seal. It’s not Darrin’s’ fault or my fault. After putting 5 qts of ATF in the trans the day before, I’m getting ready to start it for the first time in at least 5 months and I notice a puddle of ATF under the seal area. So Darrin at BC sent another tailshaft housing right out and I swapped it out and re-filled it. No leak now. Thanks Darrin! But in swapping it out, I noticed that the new one he sent had a provision for a speed sensor. The original housing didn’t have this provision. Well, I thought he was setting me up with a VSS but instead, he installed an OSS which mounts further up in the trans case. I didn’t even realize this until I got to figuring out what that extra hole was in the tailshaft housing. At any rate, there was some miscommunication between him and I and I ended up with the OSS when I wanted the VSS. So I got a Speedcal and wired it up so the speedo reads correctly.

So we got it started and the trans seems fine. So far I’ve just briefly ran through the gears on the jack stands. There were a couple of trans fluid leaks at the NPT fittings—one at the case and one/maybe 2 at the front where I installed the temp sensors. I had used Teflon paste as a thread lubricant and did tighten them pretty good. They are aluminum so I didn’t want to go crazy on them. I was surprised any of them were leaking. So now I researched some actual thread SEALER. So get this… I got some Loctite #545 industrial hydraulic threadlocker/sealant. It’s designed for tapered thread fittings, etc. I also needed their #7471 activator/primer since the aluminum is an inactive metal. So I clean everything, put the activator on, and install the fitting by hand. I get it in about a turn and it starts getting REALLY hard to turn REALLY fast with a wrench. I get it about 1 ½ turns in and that’s it. It won’t go any further. So I figure I better start backing it out before it sets up any more than it already is. Man, that thing was BARELY removable! It was very hard to remove. Keep in mind this is only after about a minute or two. When I got it out, a piece of a thread came out with it. Great. Here are a pics:





The other side of the fitting is damaged due to my attempt to remove it at all costs. You can see the threads are basically gone. What happened is that they actually bonded/seized to the threads in the case and when I removed it, the threads actually sheared off—staying in the case. Unbelievable. I’ve never seen anything like this. I have no idea how this product is supposed to work. So we tried using a pick to get the threads out but they are glued on too tight. I got a ¼” NPT tap and we were able to carefully chase the threads and re-tap it. Also, when removing that fitting, I can’t rule out that some metal debris fell into the dipstick hole. So I had to drain the fluid again and pull the pan and clean it to make sure. Ughh. Sure enough, there were a couple fragments of metal in the pan near the dipstick hole. This is the LAST time I’m draining it before I make 1000rwhp, lol.

I took apart the NPT fittings for the temp sensors and used some Permatex high temp anaerobic thread sealant. But it still leaked after REALLY cranking them together. So I’m done with these aluminum fittings and I am going to install brass tees and steel adapter fittings. I’ve had good success with that metal combo on NPT stuff. For the case fitting, I decided to go with the NPSM straight cut thread to -6AN adapter. I came across these when deciding on what to use and I finally decided after this ordeal to use the proper fitting. This way there is no sealant involved as it seals up against the case with the copper washer. That one is fixed up and doesn’t leak now. Here is a pic. The black one is the new Russell one I’m going to use. The threads are the same as the center one. The center one is the one that came out of the trans when I got it. The one on the right is a standard NPT thread. So I’ll just use a 45* swivel which will be more flexible anyway because I can position exactly where I need it.


Before starting it, I double checked the trans shifter arm to make sure it was going into all gears. But it wasn’t going all the way into each gear (PARK included). The shifter cable was out of adjustment so we bent the bracket forward slightly to get it to work. The nut on the B&M shift lever was coming loose too causing play in the shift lever. Now it goes into PARK all the way and shifts real crisp, etc. I really like this shifter now. But there’s no way that I can bolt on the exhaust on that side. It is just interfering too much with the shift lever.

Then I verified that the reverse light work and they did. When I attempted to start the car, nothing happened. I had to jump the neutral safely switch circuit that I made. For some reason, it wasn’t starting in PARK or NEUTRAL. So either I wired it wrong, the DTR sensor on the trans was bad, or the DTR sensor just needed some slight adjustment. I was leaning towards wrong wiring because the reverse lights work off the same sensor. So I lowered the crossmember, pulled the harness, did some tests and determined that I soldered one of those wires to the wrong DTR harness plug wire. I guess the wires were close in color, who knows. It could be that the harness is off of a truck which will have different wire colors. The bottom line is that I failed to follow my own rules and double check the wire colors with the pinout of the sensor. It works now!

I tested the O/D and L/U with the FB reset relay box in place. The O/D and L/U solenoids were not switching. I tested it with and without Mark Olson’s cruise control switch device. So it finally came down an issue with the correct wire from the FB unit being the power wire. There were two red wires and of course, I picked the wrong one. So I got that straightened out and they work now. Mark also sent me his latest beta 5 button box. So I wired my line lock up also to one of the cruise buttons. As I describe in the video, I also wired up an extra relay in order to cut the O/D and L/U without using the brake or without moving the shifter out of 3rd.

I was playing with the turbos a bit and was spinning them and noticed that one of them in particular was making a scraping sound. I removed both housings and it still made the sound. I took a vid of it and sent it to a few people and they all said something wasn’t right. I’ve never heard a new turbo make this sound. I sent the video to the service dept. at Precision and they suggested I send them back for inspection/repair.
Here’s the vid. You can hear the one on the left mainly making the noise:
New Precision 6266 Turbo Spin - YouTube

So I sent them back ($30 I might add). They called me a couple days after receiving them and said everything is fine. They took them apart and the only thing they can think is that one was lubricated better than the other. I did squirt some oil in it and it didn’t make any difference. So guess what? They came back and they are whisper quiet. Imagine that! What really kind of sucks is that I had to spend 30 bucks to send something back that wasn’t assembled correctly or was defective. Who knows what the cause was. I think it was the base of the fins just barely touching the base under it. But at any rate, they are quiet now like they should be and I’m glad I sent them back.

So not really a positive update by any means. A few minor set backs but that’s the way this stuff is. Actually the whole project has been this way for me. I suppose it will be worth it in the end. Here’s a quick overview video (nothing spectacular by any means):

98 SVT Turbo Cobra 4R70W Swap Overview - YouTube

I’ll have another update real soon.

 

[jbarger]

Attention to Detail

The attention to detail on this build is off the charts. I only wish i could have been there to help build this masterpiece. One of the coolest Cobras I have ever seen. Congrats.

 

[Turbo98]

The attention to detail on this build is off the charts. I only wish i could have been there to help build this masterpiece. One of the coolest Cobras I have ever seen. Congrats.

That's quite a compliment! I appreciate that.

 

[Murder Snake]

wow, sorry to hear all difficulty with the fittings...that must have really sucked. glad you were able to tap and get the threads rready to go again. nice job as always and as noted above, the attention to detail is remarkable for sure.

 

[Turbo98]

IT’S ALIVE AGAIN!!!

Well, FINALLY got it filled up and fired up again. I still have 3 out of the 4 NPT joints at the temp sensors seeping fluid. I just got the new fittings in so I’ll fix that in the next day or so.

So we took it out on its maiden voyage!! Man, I really like how everything works and feels. This auto makes this beast a whole different animal. All I can say is I wish I would have done it sooner. Can’t wait to unleash it under some serious boost. The tune needs to be touched up as it will sometimes die when put into gear (you can see this at the end of the video). But other than that, I’m really impressed with how it performs and it has exceeded my expectations so far. One step closer to completion!

Again, it’s not the best video but you get the idea.

'98 Turbo Cobra First Drive After 4R70W Swap - YouTube

 

[Turbo98]

wow, sorry to hear all difficulty with the fittings...that must have really sucked. glad you were able to tap and get the threads rready to go again. nice job as always and as noted above, the attention to detail is remarkable for sure.

Yeah, it's getting there. I've never seen anything like all this stuff. It'll get done though.
Thanks again.

 

[Turbo98]

The old turbos are out. Here’s a comparison. So I’ll get these new ones in and then get the exhaust pipes fixed up:

 

[Murder Snake]

wow, the videos were really good, particularly going over the build underneath and in the interior!!! when that beast gets set...definitely time for the King of the Street!!!! You have done a spectacular job on this.

 

[Ryan2KRedL]

IT.......... Man, I really like how everything works and feels. This auto makes this beast a whole different animal. All I can say is I wish I would have done it sooner. ....

You will be amazed when your tune is in check and you can actually get on it to make some boost.
Like me, you will never want a clutch trans again!!!! LOL!!
Congrats on getting it all back together.

 

[SVTPete83]

Awesome man!! That thing is a beast! Can wait to see some WOT pulls

 

[Turbo98]

Thanks guys. Yeah, can't wait until it's all done.

 

[Turbo98]

Got the new turbos mocked up. They fit pretty good. I was slightly concerned since the compressor housing is a little larger. But they squeezed in there. The charge pipe on the pass. Side fits better now since the internal wastegate stuff is not in the way anymore. As usual, here are a few pics. More later.

Pass. side:



Driver’s side:

 

[Murder Snake]

Looking good as always!!!!!!!!!! Nice setup for sure!!!!!!!!