In typing this up, I got word of the tragic passing of Kyle Loftis. I never got the opportunity to meet the guy but through videos could tell he was a genuine guy. It would be hard to talk to anyone in today’s modern car community that hasn’t heard of 1320video and the impact one guy and eventually his crew has had on an entire community. Without some of his videos, I wouldn’t have gotten the itch to get into cars and modify them to be fun and know them intimately. Goes without saying from everyone in the car community, he will be missed and I wish his family and 1320video family all the best through this tragic time.



So, for the past decade, I’ve had the On3 AC retaining kit on my wife’s Trans Am that has been driven regularly through the summer on the SBE LS1 for about 8 years and then on a SBE L76 (LS2 block, LS3 top half) for about 2 years. First half of the decade, I had full exhaust on the car and a cutout for extra fun/noise which after clearance issues between Fbody floor pan being low/flat as is and speed bumps, I just turned to a single dump behind the driver side.

Pic of the car as it was just over a year ago –




On the SBE LS1 I had managed 748RWHP @ 12 lbs of boost before I eventually had blowby issues I suspect from a few… oops moments with boost creep and not paying attention the gauge. Hey, things move fast at those speeds! It did have nearly 200k miles on it and had seen multiple runs into the 7k RPM range when NA, and a good handful of times pushing nearly 20psi when looking back on logs, so the motor was tired.

Being in-part lazy/unknowledgeable on building a bottom end, I opted to just pick up a complete setup and found a localish yard that that had a G8 dropout that would give me spare accessory parts for my G8 (damn unicorn cars) and a newer Gen 4 bottom end that should be robust for the abuse I had been giving the car regularly. So out came the LS1 and stuffed into a corner of the shop to be redone later and in went the L76 setup. I used the entire top half updating to LS3 heads/intake/tb knowing it was free breathing and did a Lingenfelter conversion that was surprisingly simple/nice easy to do to make the stock ECU work and gauges. We drove with this for a couple of years and regularly considered throwing it on the rollers me and some buddy’s have but always was hesitant because with the bigger everything and healthier motor came an issue I had subtly been fighting, boost creep, and it was back with a vengeance…

With the old LS1 setup, especially near the end, I wouldn’t fight any boost creep up until the top of 4th gear, maybe a little in third. With the new motor, I would get signs of it at the top of second amazingly, and all through third and beyond. I think the record was 16psi before I just told myself I would limit it at that point, in part because that is well into arrest me speeds!

Wanting to use the full speedometer we bought the car with, I started looking for ways to combat the boost creep. The method of the wastegate being mounted wasn’t the best on the On3, especially with dumped exhaust and I had considered reworking it. Looked under the hood with a buddy that does excellent fabwork and at the same time, were little things I found annoying with the kit, most specifically the alternator being the first thing to greet you when you pop the hood, and no matter how many times I cleaned it, looked filthy. I started looking at Huron Speeds setup like I did a decade ago when I got the turbo from Jon that I used on the On3 kit and reached out to him about what they had for keeping the AC and boost creep concerns.

Jon was great to communicate with and shared with me that they haven’t heard of boost creep concerns with their waste gate setup that was redone on the newer versions and at the same time it moved the alternator back to the stock location and kept everything in the stock locations. At some point I had jokingly mentioned having a stood up radiator from some sort of oops with the old stock radiator and opting to go that way and been lazy to put in a condenser, but maybe I should consider the twins! He replied back saying hey, you got the stood up radiator already, go for it! Then reassured the AC setup was nice and then shared about the fbody black Friday sales to happen.

Later in the day, wife came home from work and she knew I was looking for ways to deal with stuff. I shared with her the communication with John and the conversation went something long the lines of this –

Me – “We can do this new setup and I could hook back up the AC and make some lines for it and have tons of room in front of the engine still. Can make it easily work with what we have already, or we could just ditch the AC and go twins since the radiator is stood up!” with a chuckle.

Wife - “Let’s do two, so it’s symmetrical!”

Me – “Ya! That would be neat! So anyway, will wait to put a deposit down for the AC setup until black Friday in a few weeks and…”

Wife – “You mean for the twin setup right?”

Me – “What?”

Wife – “You are going to do the deposit for the twin turbo setup right?”

Me – “Are you… serious?”

Wife – “Ya, I want two under the hood, I don’t drive the car much during summer when it’s hot anyway and it would look cool when you pop the hood!”

Me – “You’re really serious?”

Wife – “It would look symmetrical! One is neat, but two is cooler!”

Me – “… Ok… I’m not complaining, I offered that as a joke…”

Wife – “Do they not make it then?”

I start to load up Huron’s website and go to the twins page for fbody

Me – “No its real, just stuff is going to be tight. I could make it work for sure, may have to move some stuff around is all.”

Wife – “well lets do that then, especially if he is giving us so much free stuff on Black Friday!”

So, conversation went a really different direction than I had thought… In the back of my mind I just remember the old stories on LS1tech of people talking about single vs twins and the most common comment of “unless seeking huge power, you are just doubling your cost of everything.” Ok, well some of the double cost was covered, so guess will go that way with things…

At this same time, I took the time to look at what else the car would need. I had been tuning it and fighting with dumb stuff regularly, chasing my tail on it smells at an idle, now it cruises too lean, now it bucks too much and always making progress one way in the tune and then fighting with something else popping up as a result. Slowly making progress in dialing it in but was getting old and I just didn’t have the patience anymore for it. I had dug around and found that people have piggy backed the stock ECU with Holley Terminator and started to that direction. I reached out to Current Wire Performance and got a harness from them to integrate the two systems together and during black Friday ordered up a Holley setup.

Now I remember when I took off the clutch when switching engines, it was worn and figured it maybe had another year or two of life with it. I did a bunch of reading and talking with buddies and everyone swore by the Monster Triple Disc. Truth be told, I threw in a Stage 2 single almost 13 years ago and almost immediately it had a rattle. When I first put on the turbo the disc fused itself to the pressure plate in my first couple of outings and went Mcleod RXT because going from memory when talking with someone at Monster they had said I installed it wrong. I understand people get things wrong and them being a business see it all the time, but I remember it left a sour taste in my mouth, and I always scoffed at buddies putting them in their car. I eventually swallowed my pride and ordered up their triple disc setup. With the price of it and praise for it, I had a pretty high expectation it better be damn near perfect. I was surprised to open it and see a new slave, but in talking it through with a buddy, they obviously had to make their own proprietary setup for the extra distance with the triple since they couldn’t use a stock slave.





Stuff started arriving and as it arrived, we would stack things in the car while we had it tucked away for winter. Eventually I had everything but the turbo setup. Jon was great about communication with everyone on ETA and eventually I had enough sitting in the car I decided I just wanted to put stuff on, would enjoy the car for the summer and then put the twin setup on during winter maybe. I started with opening up the Current Wire Performance harness and Holley harness and piecing together in my mind how things would go and be laid out over the car.



I dropped the engine out of the car and pulled off the stock harness. I had already trimmed a lot of it due to sensors I no longer needed and to clean up stuff under the hood. Always was a pain too when looking at a sensor and trying to remember where it went even after the amount of times I have been around this car.

 

As I started into all of this, I got a notification that some packages were on the way. This was about to get a bit more involved than I had expected when I started into it with only an expected “maybe down for a month or so, be able to drive plenty through summer!”




I was blown away with the quality of everything in the twin setup, and of course the packaging. No expense seemed spared to make sure stuff arrived safely and was at the same time easy to get into. During the time of this, I had started putting the Monster triple on the engine and with the quality of what this all looked like, money well spent and a true piece of art with quality and attention to detail. The company logo etched in on the aluminum is a nice touch.


Stuck it on the car with it all down and in this pic you can see the old discarded RXT and the old Turbo setup as it was dropped out. The flywheel I discovered didn’t match up 100% with the RXT and the inner fingers of the disc that mounted against it hadn’t been used at all. Totally forgot to snap a pic but was telling that I was near the end of life of the clutch.


After mounting the clutch, the next step was to mount up the turbos to have a glimpse of what I would see under the hood. To say I was giddy about it would be an understatement.


Much itching and wrapping later, I had more hotside pipes on


You can also see I started routing through the Holley harness and worked on trying to keep things tucked out of the way as best as I could. I then had to incorporate the stock harness to everything and then anticipating issues with reach, plugged in as much as possible and routed as best as possible.


At this point, I was ready to marry the engine/trans back to the car. Wife came down and helped as another set of eyes and things were tight as expected. Going off of memory, I actually pulled the turbos off with concerns of them hitting on the frame as the car came down and just driving everything south at that point.


Once in I then started routing wiring as best as possible out of the way and then started to notice where there were clearance issues. First up, I know Huron mentioned the ABS would be an eyesore and suggested removing it, but putting on a small cone filter, it just wasn’t gonna fit. Friends suggested just doing a turbo screen, but with as often as the car is driven, rain or shine, I preferred a filter because I would feel like a real bum on the side of the road if something decided to get ingested/destroyed.

Next the radiator pointed directly at the turbo. I had tried to find stuff of others putting on this kit and how they approached it and found a video with only glimpses of this and doing a 90* hose and running it along the radiator. With where my radiator was mounted through, there was less than 1* of space to make this happen. I kept searching and found someone else in the FI section that had one of the kits a few years ago trying to tackle the same issue, poked around their profile looking for pics/ideas and found that it looked like they sold the kit and went the Procharged F1 route. At this point, I’d be lying if I didn’t seriously consider throwing it all back in the box and trying to post it all for sale and let someone else braver than me tackle it.

At this point, Wife said do whatever it takes to make it all work and go as far as possible until we know for sure it doesn’t so I started piecing things together. I ordered up an SJM ABS delete kit, relocated the battery to the rear, started tucking things and moving forward with stuff.

 

Being OCD about dash lights and errors, I even pulled out the LED bulbs on the dash for the ABS/Brake so they weren’t staring me in the face every time the car started up.



As things slowly stalled, there were things I would of course keep looking at and thinking would be nice to update the car. Told myself this could be the once a decade revitalization that the car seemed to go through! We got some new LED/projector headlights that actually look nice and provide a lot more light than the old halogen and even projector setup I had on it for a bit.



Being the Joe Dirt esque person I am looking at things I can’t afford or neat things on Craigslist/Facebook marketplace. I found a new down the road project I had to jump at because it was something I have yearned after since getting my wife’s Firebird.


I had wanted a 400, but this for the price and being a stick was hard to pass up and looking underneath, the bones of it seemed really good. It has a Pontiac 350 in it and initially had plans to keep it all Pontiac, but in digging and doing price comparisons, this might go the way of the LS. Especially after visiting car shows and seeing a lot of old Pontiac motors and some with SBC 350’s, doesn’t seem to be many LS conversions in my area so doing that is down the road possibly, with some boost on the side maybe…

At this point, summer had nearly passed us by and I knew there was no chance to have the car running/driving between life and constant obstacle popping up. Black Friday was upon us again and I started looking at stuff and stumbled upon Hawk’s and their reproduction pieces they do. Our headliner after 25 years had slowly gotten gross from ttops being left off in weather and age, so we got a new headliner and Visors from them.





And some new skins for the seats.


Holley ECU sits behind this kick panel along with the power cables for the rear battery and some of the other misc constant lines to a power distribution block I found on the jungle website.

We also did a new center console as ours was slowly developing slack where things were mounted. I also had gotten some other used bits from them honestly expecting something I could have found in the local wrecking yard had I gone to dig through a car that was there, but I will say, what they sent was near brand new quality. If I handed them to someone to tell them they were new, would have been hard to disprove. I would highly recommend that if you needed any Fbody parts, it is worthwhile purchasing from Hawks. May be a higher price, but you get what you pay for.

 

At this point I had spent so much time and money trying to ignore the elephant in the room of the radiator. I told myself if I got this far with everything I had to make it work, so I cut out all of my old pieces that were booger welded in and started mocking up stuff and options. I had considered ditching the hood latch in favor of hood pins, but the wife vetoed that. Even the newer aero latch setups like what a friend has, she wasn’t a fan of. In mocking things up I had realized, not only was my top radiator hose going to have issues, but so would my lower. The point to get it to the thermostat housing was so small and tight I was concerned over time of the hose possibly melting. At the same time I had the same concerns with the turbo drain lines and tried to do some hard lines. Not able to radius as tight as I wanted, I opted for a lot of AN extensions. Not ideal, not at all what I wanted, but at this point, it worked.



The gap to the left is what I had to work with for coolant. I eventually started poking around and discovered Autoplumb to convert things to AN. Their pictures of their stuff looked nice and I would feel better with some AN hose over some rubber and this gave me flexibility to move/direct things how I wanted. I got some of their stuff and adapted it and gave me ideas on how to mount things and how much wiggle room I had to move things around to work


After being happy with how things sat, I then built a bar on the bottom and sat the radiator in there.




Was then able to make a upper radiator hose and run it over to the outlet of the water pump with the Autoplumb fittings.



This left the lower radiator hose to go in and did a bit of pondering on this. I eventually decided to loop the hose off at a 90 from the radiator, come up where the old overflow was now that it was gone with the battery in the back and then run it to the thermostat housing. Also got a nice bracket for my mightmouse can too!


Radiator fans clear just barely over the hoot latch setup.




At this point, I could see the light at the end of the tunnel, now I just had to hook up charge piping and then could give it a good crank, find leaks, then start on the tuning of dialing in the Holley.

 

Soon after this, I went to put the bumper on and ran into an issue a flashy trans am would, the fog light molding in the bumper made contact with the intercooler before it could even be bolted on entirely.



I was a bit frantic in the face of another hurdle and then just did the thing that was obvious and started cutting. I pulled out the Dremel, cut until it cleared while crying on the inside knowing to replace the bumper if I did anything dumb gets harder and harder every day to replace. Eventually it was on the car, called the wife, had her drive it up the driveway to clean off the year of dust that had accumulated.


At this point, I kept getting a check gauges light. Plenty of oil pressure, fuel and temp gauge was reading fine, but the voltage seemed to be on the lazy side. I put in resistors thinking something was wrong with signal from the factory ECM and could get the light to go away, but wouldn’t sit around the 13 volt range. I eventually ordered a new Powermaster and pulled out the old truck alternator from the car. Taking off one turbo from the side was surprisingly easy, putting it back in though… not fun solo.


Volts fixed!


At this point, the wife and I would go find some reasons to go drive the car and start dialing in the tune. After feeling it was ok to drive, she actually drove it back and forth from work in the rain with no issues that she could notice. I would go to the car in the evening, pull the SD card from the Holley, download the logs, make some fine tuning and send her on her way. Goal was to do the proper break in for the clutch for the 500 miles regardless of weather to go dyno the car.

Did this for a week until I took the car one day to a friends shop to get an alignment done because I could see some crazy tire wear. I drove it for the day, visited friends on my day off, and on the way home stumbled upon my parents and decided to give them some noise. I went to pass, had it in 4th being easy on it when at about 3800 rpms a sudden sputter. Looked in rearview mirror and saw a puff of blue and then thought great – I might have lost something. Glance down and I still had revs, but was clearly misfiring. Limped it home the mile away from home I was parked the car did a preliminary look and saw nothing and went and had dinner with the kids while wife went to play games with friends. She came home, told her I’m sorry I broke her car the one day I had it, she laughed and I went to start it. Seemed ok but maybe a little miss. Tried to drive it the next day to visit a friend and got part way down the road and decided nope, drove back home and parked in the shop.

Did a smoke machine to look for any lines that might have blown off causing weird conditions and saw nothing, so decided to just check the plugs and when I pulled off # 8 was greeted with a self gapped plug.


I scoped in there and saw what best I thought was piece of a piston missing. Pulled everything back apart and took off the head and something definitely is missing!




It’s always hard to diagnose exactly what went wrong, but have put this through some abuse already with the single setup that was on it so was surprised when this happened. Looking back at the log, I was at 35% throttle, 16* timing, 3580 RPM, 7# boost and 11.2 AFR when I lifted when it happened. Earlier in the day it had multiple WOT runs at it and didn’t miss a beat so was a bit of a head scratcher for it to happen in those conditions, but figure it must have been a peak torque issue maybe. Additionally, in first setting things up on the Holley, things were Lean and I crept up on the ideal/rich side of things rather than just throwing it immediately to super rich. I suspect that in the lean conditions there could have been some underlying damage/weakening to the piston and that might have been the cause. My G8 ironically lost the #7 piston a few months before tearing into the car from the fuel system being erratic I suspect from possibly similar conditions.

I had ordered up some Summit goodies and plan to go on another learning adventure of redoing a bottom end, and this is where it sits today!



Have one friend that has put plenty of abuse on these and sings their praises and I can’t seem to find anything negative about them and to do better would be big money. Plan for the car is possibly hit the four digit mark just for bragging rights but in reality, drive it as a fun car with something neat under the hood. I’ll try to remember to come back after putting stuff together and update after I throw it on the rollers with how it is. First impressions though for the first week or driving, damn is this fun!

If you’ve gotten this far in reading through everything, I hope I didn’t bore you too much. I remember in the heyday of LS1tech/forums seeing stuff like this and did one on my previous build you can look for and wanted to something similar for this one.

Special thanks to Huron Speed for putting out an awesome piece of eye candy. Though I anticipate I won’t use it to it’s fullest potential, it always puts a smile on my face when I pop the hood and even when seeing people’s reactions to it. The Fbody is unfortunately a deceased platform and has moved onto other things so for people to still make new things for these cars is always appreciated with how the market for them is dwindling due to the age of them.

 

Definitely a long read but some good stuff. Sucks about the ringland. Something similar happened to me during a WOT pull. Car drove fine after. Pulled plugs for typical maintenance checks and found the plug gap closed in a similar fashion.

The Summit stuff is great. You won't have any issues with it. Good luck on the rebuild.

 

Very cool. I am about to bring mine back to life with the Huron twin kit as well. Ill have to look back on this for the help with the hurdles you had so thanks for the thread!

 

I'm hoping the Summit stuff is going to be more than I will ever need. Buddy has pushed 26psi on his without issue multiple times which is way beyond where I plan to ever be pressure wise. At this point the weakest link in the drivetrain is a toss up between the physical block maybe or the Magnum F behind it. As long as it goes another decade before I need to do much to it, I'll be happy!


If there is anything don't hesitate to reach out. Best advice I can give is have the radiator as far forward as possible because you will need it. Probably different ways to go about mounting or size or anything like that but goal was to make it look good under the hood and maybe even down the road switch to a mid mount setup and put AC on the car. In measuring up the BTR/Holley Mid Mount stuff, it theoretically would fit a compressor up top.

 

What size AN fittings did you go with for the engine coolant lines?
I'm looking at doing the same but am unsure what size, thinking -20AN since I street my car a lot and want as much flow as possible but thought I'd ask.
Does your car stay cool in heat and low speed operation?

 

I opted for the 20 AN, was largest they sold. I'm sure there could be some loss of volume/flow downsizing since the ID was a bit smaller than stock from the lower I believe it was, and it was one of my concerns but seems to have no issue at this time. The hottest day I drop it was mid 70's and from what I recall temps never went above 187 which from memory is the first fan target temp I have and pulled down easily. If I did it again, I might have opted for having a buddy build an intermediate hose, but it was kind of a experiment for cleanliness/bling bling. Fittings are spendy so try to make sure you buy the right angles you need. Autoplumb has templates on their website that you can cutout that are to scale to mock up with how things will fit.

I have a Motion Raceworks 4 corner kit and the line I had made for plugging into the radiator didn't seal correctly, suspecting they might have used an SAE because the car always leaked and didn't seal against a possible JIC, or vice versa. When I tore it apart to do this whole setup, I discovered the radiator was down to the bottom third or so of the capacity because that fitting was always leaking. On the handful of 100 degree days I had driven it with the old setup temps would peak around mid 190's in traffic but pull down really quick with both fans kicking on. All this to say, if your radiator is adequate size, I suspect you would be fine even going with the smaller size - within reason of course! I have the traditional Griffin everyone does when standing things up and no issues at all with temp control.

 

Monkey Fab probably has the cheapest (cost) 20an fittings and hose on the market. Just FYI

 

I appreciate that.Yeah mine is already moved forward but I'm definitely thinking more. I'm considering a tubular front end that might open up a ton of room. I'll try without first though.

 

Great build thread! I have a similar build, but used a Huronspeed single turbo setup. I will say, Huronspeed's craftsmanship is top notch for sure. Plus, they're willing to make custom one-off parts when something in their kit doesn't fit. My driver's side intercooler outlet pipe had a blow off valve standoff that wanted to occupy the same space as my turn signal ( I have a Formula ). Got ahold of them and they made me a new one to my specs and even powdercoated it as I had paid for powdercoating during my original purchase. Great customer service!

I have two questions - 1) Do you have a link to the headlights you bought or what the name is? 2) Where did you get the seat covers?

 

Headlights came from Genssi, $200/set. Come with I believe an H11 pigtail you can snip and throw on spades to plug into stock connector or snip off the old connector and convert to the H11. I opted for the later because my connectors were a little on the nasty/worn side

Seat covers are Katzkin from Hawks. I believe it was off the shelf that they stock. Not sure on Formula seats, but on Trans Am it has the plastic rear cover so requires to have it separated and restitched in instead of wrap and hog ring. Considering the skeleton of it was 25 years old came out pretty good but if your OG seat is in better shape than mine probably fit better. Over time probably settle/wear with some creases better as it already has in the last few months. Definitely great quality.

 

Cool, thanks for the info. My car has base model style seats with no lumbar, so they should be relatively easy to recover. As for the lights, I need to do something and I don't care if they look factory. I'll check those out.