Building a 7sec 87GN Drag-n-Drive car with V6 Stage 1 heads!

turbobuick

Well-Known Member
Staff member
Joined
Jun 18, 2001
I've been meaning to make a post about my 87 GN which I raced in TSO for many years and have a ton of stories and history with and I recently bought back. It is hard to make a thread about this car that dosent turn into a novel! Plus this site is so sketch to take the time to do a nice build thread and have it vanish due to a site crash or not be able to edit any of your posts is ridiculous. But here goes I will try to keep chat to a minimum and post a ton of pics. Feel free to ask questions I really don't keep any secrets about my builds.

Some of you may remember my GN while newer members may not, and a bunch of you old people have probably just forgotten! I raced this car pretty much like you see it up till 2010 when I sold it since I was in the process of building a new 25.3 chassis. I really did not want to cut this car which is a clean 34k mile GN to put in a 25.5 chassis. The gentleman I sold it to keep the car in storage pretty much untouched till I bought it back from him in 2021
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I brought the car home in pretty much the same condition it was in when I sold it in 2010. Except for the fact a car like this does not age well!! It leaked everything from everywhere, all the certs were way out of date, all the fuel lines were junk, it leaked coolant bad and was a real mess. And the good ole Accel Gen 7 that was still in the car needed a place in a museum!!

I ended the 2009 race season with several personal bests. We, and when I say "we" I am talking about me and my best friend Ray Mills who has racing with me for close to 20 yrs now!, At the time we ran a GN1 head in a car and ran a best ET of 8.14 and best MPH of 174mph at 3450# In 2009 this was the fastest anyone had gone with Stage 1 production style heads. Yes it has stock PM brakes, yes that is a 70mm TB 3" IC pipes with a full stock interior on an ETstreet drag radial with relatively stock suspension. TBH after getting the car back and looking at it, if I didnt know the car and someone told me how fast it was I would have thought they were full of shit!

These pics are from 2021 and the car is pretty much exactly like I ran in 2009.
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I got the car back in April 2021 and initially my thoughts were hey lets clean it up and make a few small updates and go racing! When I sold the car I had a brand new motor in it that was the best of the best stuff you could have at the time, actually even still today. I figured a few small updates and changes and we should be able to get the car in the 7s on a good track, why not right? Lol.

I had several car projects going on in 2021 I had to finish or sell which I did but then started a home renovation in Nov 21 in which we lived the basement till March of 2022! So the car sat another year till March when I finally brought the car home and started tearing into it. We cut the old cage out, pulled the motor trans and pretty much everything apart. Yes that is my Buddy Ray in the pics working on the car which will be pretty common in this thread!

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While I didnt start tearing into the car till March of this year I did start acquiring parts for it last year and got a little carried away with Black Friday deals in 2021! One of the things I picked up was the Merillat rear crossmember and TQ boxes which were just to sexy to not buy on sale and a must have on my new build. However, installing them was not something I wanted to tackle in my garage and really needed a chassis table for. I called my old chassis guy who has since closed his shop and retired but still had a home shop he did small jobs out of and was willing to take care of installing the crossmember.
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Nice- I like the effort going forward to complete a frame restoration modification on a real GN race car.
 
It was March and the Buick Nats were a few weeks away, my Ttype was still in Storage and Ray was working a gazillion hours a week putting his own GN back together to get ready for BG after tacking a frame off paint job over the winter.

A little side note on my buddy Ray's GN. We made it to BG with his GN and my Ttype and his GN turned out absolutely stunning. He spent all weekend polishing it and putting trim moldings back on. So I went and bought him a tech card and race ticket he FINALLY decided to take it down the track at the end of the day on Thurs and ran an 11.0@ a whopping 132mph! (109 Stroker motor GN1 heads, BB72mm turbo.) The car had more miles on it driving around the pits and going down the track than it did since he finished it he literally drove it once around the block before loading up for BG. He definitely should have entered the car show.

Ray did all the heavy work on the body and Rob Ortosky did the finish work and sprayed it with the body off the frame. Pictures do not do it justice the paint work is probably the nicest Ive seen and Ive seen and done a lot. It should be back BG in the spring he is excited about getting back out. The car has not seen light of day since BG and after Ray has owned the car for over 10 years BG was the first time I ever saw the car run and drive lol!
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The tale of two motors!

I had two motors for my GN when I was racing TSO and kept the one motor which was considered the "back up" motor and I sold the GN with the "good motor" which was the original motor I had in the car. I planned to use the back up motor in the 25.3 Drag radial car I was building at the time. I ended up selling the 25.3 car after it got lost in chassis shop hell then was off to the body shop abyss. In 2016 I had enough it was 8 years into the project and I had zero desire to finish it. I sold the roller to my good friend Tommy Robison who finished it raced it and sold it and is now on at least his 10th project build since then lol!

I ended up selling the motor to another friend of mine Manny Eker who unfortunately Manny passed away in early 2021. This was a big loss for the Buick community as he was one of the true innovators and pioneers of building and racing turbo buicks. On top of just being a nice guy who was quick to share advice and knowledge when I was just starting out racing TSS with him back the 90s.

After I bought the GN back I caught word that Mannie Jr was selling the motor and not going to use it in his Dad's WE4. I really wanted the motor for a set of TA heads I put on it that Dan Strezo did and flowed a ton. The motor I sold with the GN had a set of RR GN1r's made with the newest castings which were not even for sale at the time when I finally got them from Tom. I had literally broken every head Champion had ever made and while Tom was good at taking care of me I really wanted a TA casting they are just beefier, have better geometry and actually flow more.

So after I picked up the motor I now had two motors in which I wanted parts off each. Originally it was just going to be a top end swap but I tore the whole motor down and went through it changing a bunch of stuff. The motor in the GN had zero passes on it and outside of one low boost pull on a chassis dyno which it put down 1000hp it was pretty much a new motor.

I told you its not easy to make a thread like this without it turning into a novel! Here are some pics of the motors and some good engine porn. I am in the process of final assembly of the motor and will post a write on specs and details when its done. In the meantime I thought about doing a whole separate thread on the motor and differences in Stage 2 blocks. I had at least 5 of them come through my garage in the last year in several different configurations of which I took a bunch of pics that show a lot of the differences.

Here are both the motors I ran in my GN. The motor in back ground is the GN1 head motor that was in the car when I sold it. The TA head motor has no VC and a BB7675 and the GN1 motor has the PTE 4788 I ran back then.
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Here is the GN1RR head motor mocked up with a killer Danny Bee belt drive set up DLS made for me. I ended up selling the belt drive assembly after sold everything else. I wish I kept it.
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Next is my 0012 Stage 2 3.8 offcenter stroker motor that is currently in my Ttype. An off-center block is pretty much a bolt in for a 109 motor but does require some extra mods that are well worth it. You can even runs a factory style oil pump and front cover which this one has as opposed to the TA/Duttwieller setup. I replaced a girded 109 stroker motor I had in the car originally which I grew tired of the oil leaks. I freshened it before sending to a gentleman in Atlanta some pics of the two.
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Next up the on-centers. These are more plentiful and significantly stronger blocks with casting number 00153. They came in many different configurations I have three of them I can show pics of. The first the most common 153 that has x-bolted front and rear caps no oil dipstick no internal wet sump provisions. The second is an early 153 with the oil dip stick and is not cross bolted and can actually be machined for an internal wet sump pump like the off-center blocks. This block went back together with parts from both my motors, the new DLS pistons, rotating assembly out of the one motor and the GN1RR heads and top half off the other. I also sold this motor but regretted not keeping it as a back up, so I bought another one two month later lol!
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More engine pics
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153 block with roller cam bearings, this is the block I ran fast with.
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The 153 block I am using is actually a 6 bolt center mains with 4 bolt front and rear caps. For some reason I can't find any pics so I will continue post tonight.
 
Wow that is living the turbo buick dream. I would love to live in your garage. Makes me remember how small time I am. But I love my Buick and appreciate what little I have.
I am so sad to hear about Manny as he worked on my car back in the 90's. Great Buick loss. Loved his we4. Was sick when he wreck it go to BG 1 year. Anyhow its your thread. 😞 SORRY MANNY
 
Great write up and pictures. You super super fast guys live in a exciting world. Thanks to all your buddy's that can help you. Your cars are beautiful and full interior. wow
Keep it coming!
Steve C
 
On with this build I have 6 months of pics to post yet lol!

While I made the decision to cut the car up to make it legal for 7s I also decided to keep it as much an 87 GN as possible. If I didnt need it to run 7.50s or I didnt need to cut it out to install the chassis I wouldn't. So I made a list of things in my opinion were must haves keeps with upgrades that were necessary. For the interior factory dash, console, rear seat, glass, door panesl carpet etc. For safety and to get in and out of the car afternarket steering column, quick release wheel and Kirkey race seat. I kept the factory front suspension and frame and steering with S10 manual box and Trick Chassis UCA LCA stock spindles and Wilwood street brakes.

For rear suspension I shopped a bunch and ended up going all in with Trick Chassis. Alex was the only one who offered to get a rear housing done in a time frame I needed and at a decent price to boot. Alex delivered on time and the service and quality was excellent, I couldn't have been happier.

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After I got the frame back from my buddy I tore it all down and had it sandblasted and then put in an epoxy primer which if I had to do it again I would have used a weldable primer. I used a Genisis Epoxy from Sherman Williams which looked great and was tough as nails but we had to grind a ton of it off to for all the welding that was coming up next.
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Started prepping for boxing the frame
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Ray working again, notice the sparks and his shoes and shorts not a good idea ask him how he knows lol!
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Now the fun begins and we start construction of the 25.3/25.5 roll cage. First thing you need are the SFI rule books which I ordered. There is very little difference between the two specs in a Gbody with the 25.3 being a 6.50@3600# cert and the 25.5 which is a 7.50 cert. I really only need a 7.50 cert but the differences are basically tubing diameter, additional gussets and an X-brace in the roof most of which I am going to put in this build and I will point out the differences as I go. As of today we are about 75% done with the cage and have not gotten and inspection yet but I am working with and in touch with the NHRA inspector as the project progresses. I will probably end up with a 7.50 cert but will only need to add 4 dash bar gussets to get the 6.50 if I ever need to go there.

The SFI requirement is to box the frame with 1/8 plate and the factory frame can serve as the 7a and 7b outter frame rails of the roll cage. Which is what we did in the pics above. Trick Chassis sells a really nice laser cut kit to do this and it is really inexpensive. I have seen others charge 2-3x what TC is for the same basic kit. Fit was spot on along with the opening for the body mount. We also used 1/8 plate welded to the factory frame at every point a CM bar had to be welded to the frame. This gave a nice clean and strong location to weld the cage to the frame.

Equipment:
The cage has to be chrome moly and has to be TIg welded you are not allowed to mig weld Cm tubing anywhere according to SFI and NHRA specs. Tig welding takes some skill to learn even on a flat surface sitting at a bench and gets more even more difficult when welding tubing and is just plain nuts to try and weld tubing while laying upside down inside or under a car.

To get started in Tig welding I bought a Alpha Tig 201XD to learn on but it is a pretty steep learning curve and TBH I don't practice nearly enough to be good enough to weld this cage. Ray on the other hand while also new to Tig welding had been an iron worker and has years of experience and training in welding and was able to pick Tig fairly quick and is laying down so really nice welds at this point. He is also a surgeon with a Metabo cutoff wheel and grinder!. So pretty much all the tig welds on the car will have been done by Ray.

I also bought a Model 32 JD2 bender with 1.5 and 1.625 dies. The stand came from Tricktools.com. I did the SWAG off road HF Hyd air ram conversion. It took FOREVER to get all the parts to put the bender together and actually had Sam Balls in Texas buy me a HF ram at his local store and ship to me as it had been on BO and you couldn't order one online for some stupid reason.

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After plating and boxing the frame we were ready to fit the first bar for the cage which is the #1 main cross-member. The placement of this bar is pretty important since most of the roll cage is based off of it. You need the bar low enough that the driveshaft doesnt hit when the suspension extends and it has to be high enough for ground clearance especially when pulling it on a trailer. My previous 25.3 build I sold was a real PIA to get on to a trailer because of this and didnt want to make that mistake again so we spent a lot of time mock stuff up and fitting the bar.
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Note on materials, where to find them especially with inflation and supply chain issues! The only place I could find to buy CM tubing local to me was an 1.15 hour away in Cleveland and they could only get 1.625 .083 and no idea on when or IF they would have 1.5 .065 and it wasnt cheap. The best deal I could find was actually Applied Racing Tech in Clearwater Florida and they claimed to have the largest supply of CM tubing anywhere and I believe them. Plus I was going to be there in April for Spring break! So I took a break from the beach one day and grabbed an Uber over to check it out and purchase most of the material I needed to do the job. Thier pricing was actually cheaper than the local supplier and while I had to ship truck freight the cost difference was minimal. I was able to order 20' sticks of 1.5 and 1.625 and I also bought the main hoop and the crossmember pre-bent which was WAY worth it! The fit on the main hoop could not have been any better. The main hoop required 12' of CM and is the most difficult piece to bend and get right and I was certain to mess it up at least once and even if I got it right I dont think it would have fit as tight as the one I got from them. The longest piece of tubing you can get shipped UPS is 8' so if I needed another 12' piece it was going to be $$$$. They charge $60 to bend the main hoop, no brainier! Plus I got to meet them and see their shop and they gave me a cool tshirt! Thumbs up for ART!

Next step is to start fitting the 2a 2b inner frame rails and laying out the trans x-member which is part of the forward crossmember 6a, b and c bars. There are a couple of things to note here that I was told but not necessarily in the SFI books. With a frame and body config on a Gbody the inspectors like to see the body actually welded to the cage at some point especially on a 6.50 cert. So instead of trying to drop the inner frame rails down under the rear floor pan we decided to channel them into the body and weld them to the cage in the end. Which meant cutting my nice clean rust free 34k mile GN floor pans!


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Also worth mentioning that is not in the SFI book the rear frame rail notch. If you notch the rear frame rail all the way to the inner rail and dont box it you will need to run the #2 inner frame rails past the rear end. My frame rail notch was boxed and not down to the inner rail and the inspector approved it as acceptable for that inner rail even on a 6.50 cert plus I only plan to run a 275/60 radial and keeping the stock wheel tubs.
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After fitting the bars and tacking everything in place we decided to fit the body cut the floor pan and move the whole mess down to Ray's shop so he could finish welding all the floor bars. I picked up a set of TRZ alum frame bushing and got the standard height ones too which I recommend for floor pan clearance which was an issue fitting the body back on. What we thought was going to be a 2-3 hour job turned into 9 and we raised and lowered the body so many times I thought I was going to wear out the lift! We ended up having to completely re-do the trans x-member from what we had plus a million other little tweaks.
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Once we got the body back down to Ray's shop he removed it and put in on another rolling frame he had from when he did the frame off resto on his car. We put the frame on his lift and stripped it completely back down so we could flip it over and move it around by hand.

It doesn't look like much welding but it takes a ton of time to Tig weld. Ray has really only been Tig welding for a couple of months at this point it this is his first attempt at welding tubing on a car and not sitting a bench. He spent hours getting it done but and the welds turned out fantastic.
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We loaded the frame up and took it back to my buddy's body shop for a final coat of epoxy which looks great as a chassis paint.
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Time to start reassembling everything again. Mounted brake tabs and had rearend housing poweder coated silver strain.
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Next up I took the body to my buddies shop to have the firewall painted. The car was re-painted in 2007 after a shock, wall incident at Norwalk, and the paint and body are still in fantastic shape today. I am hoping to be able to just do a paint correction wet sand and buff when the car is done and hopefully we dont put any extra dings or scratches in it during this whole process.
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While the body was still on the roller frame I was able to start fitting the main hoop and constructing the rear funny car cage
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We planned to bench weld the main roll cage instead of trying to do it in the car which turned out well. You can see the main hoop in this pick with the chassis right before putting it all back together

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I finished assembling the frame and rolling chassis and we were able to mate the body and frame back together and final fit and tack in the main hoop and start test fitting the driver
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Time for an update!

I left off on this thread where we were some time in beginning of October and Ray and I were on a roll with the car up through November when we took time off to go down south and do the drag-n-drive event with the Ttype.

Teh next step was to bend the Apillar bars which I had been losing sleep over trying to figure out how to bend. I knew I needed 3 bends in the bar with an offset but had no idea how to do that. Everything I found showed how to bend the Apillar bars with two bends and an offset or as a halo set up and I was running Apillar bars with a windshield bar and not a halo.

When bending the Apillar bars you need to bend them at the same time and they need to be identical since you will have a dash bar and windshield bar that will fit between them and you will want them to land in the same place and look symmetrical. I tried to make a template out of PVC conduit which did not work so well.
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The first set I did I only put two bends in and did the third to try and offeset the top bar. While I was able to tweak the bar to "fit" it wasn't ideal and when I went to make the drivers side I quickly realized it was not going to be possible to make that bar identical the one we spent an entire day fitting in the car.

So here is the first set of Apillar bars and the 16' of wasted 4340 tubing!

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Second set I figured out how to do the offset with a third bend


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I was able to bend both the same and they literally fell in the car. We fit the foot and coped the main hoop end then made the dash and windshield bar.
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After we got the windshield and dash bars tacked in we planned break the tack loose and lay the front cage back to weld the dash and windshield bars. Well we took it one step further and ended up being able to weasel the whole front cage out of the car and Ray was able to finish welding it on a bench. I was also able to get a nice coat of paint on the back side of the bars. Once we got the cage back in the car and tacked in I started fitting the dash and test fitting the driver since I had to determine where the funny car cage bar needed to be.
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Once we got the seat positioned I was able to figure out where the FC bar would be and I found an electrical conduit that was 1.51" in OD and fit the die for 1.50" tubing. I bought a 10' stick and bent two of them up first one way off second almost perfect. Third I bent out of 1.5" CM and went in the car.
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This was right before we left for the drag-n-drive event and didn;t get back on the the project again till the beginning of December. Once we did we fit the FC cage bar and then started on the roof structure. The first attempt at the roof x-brace ended up being wrong since the diagram in the stupid SFI book is wrong! Good thing I have been in communication with the NHRA tech inspector who sorted me out.
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This is the first attempt at an x-brace I had to cut this all out and re-do it.
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Thae FC bar was actually a lot of work to fit since on the one end it had to fit and mate up with three other bars and the other end was on the Apillar bar and at an angle coming off a bend. We got the one end coped and fit really nice but it ended up the other end where we couldnt see until we lifted the body had a huge gap. We also think part of that issue was the bar being pulled while welding without the opposite side tacked.
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After I spoke to the NHRA chassis inspector and found out the diagram in the SFI book was wrong I tore out the x-brace and we moved the car back down to Ray's shop to get ready to raise the body and start welding the top side of the cage. The fun part where Ray learns how to TIG weld lying upside down in a cramped space. If you ever wonder why there are so few cars built like this it is because of this, most will cut the entire floor out and make the body removable which is WAY easier than trying to do it like we are.
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I channeled the #2 bars into the floor pan and still have most of the factory floor pan in the car. This way we were able to use the lift to raise the body which we managed to get it pretty high.
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Once we got the body up Ray was able to finally get a nice weld where the cage meets the frame. We plated it beforehand which made a nice clean and strong attachment point
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The biggest difference between a 7.50 cert and 6.50 cert is the roof structure. I really only need a 7.50 cert but once it is done it can't easily upgraded as once he door diagonals are in I won;t be able to raise the body. A lot of the tubing diameters are also larger for the 6.50 cert which is what I used in the build. I finished the roof -brace and gussets, it's just a few extra bars and welds lol!
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Ray welded it up
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We then installed the rear down bars behind the main hoop
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And after a REALLY long weekend we got it done! and the body lowered back down on the frame.
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It is a nice feeling that the hard part part of the cage build is done. The car is coming back to my shop to have door diagonals, outter FC bar, Kidney bar and dash bar gussets done and it will be ready for cert! I have some additional bars I plan to run in the rear and also going to re-do the chute mount so there is still a lot more work that still needs done but it looks good for making it out next spring. We are not making Sick Week with it. Doing the DnD event in November then the holiday we pretty much didn't work on the car the entire month of November. These pics are from last weekend so that brings things up to date. With the car at Ray's I have moved on to putting the rest of the motor together and will post some pics and details of that soon.
 

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LOL. I was wondering how you could lift the body with back bars in. Of course now I see they weren't welded.
 
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