Chevy Nova Forum banner

69 Nova 408 LSX with twin turbo track debut

14K views 36 replies 18 participants last post by  Sooner1 
#1 ·
It's been a while since I visited the Drag Racing SNS page. My '69 Nova has been down for the better part of 3 years while I did a LSX conversion, front subframe upgrade, and twin turbo installation. Over the past couple of weeks I finally got it back on the ground and logging some street miles. I plan to re-introduce it to the local 1/8 mile dragstrip this weekend for some test passes.

A quick run down of the drivetrain: 408 LS iron block (based on a 6.0 truck engine); 4" Callies crank; 6.125" Callies rods; Wiesco pistons; main&head studs; AFR-225 CNC ported heads; Victor Jr; 4150 Accufab throttle body; 80 #/hr injectors; GM ECM & harness modified and tuned by me using HP Tuners; twin Turbonetics GTK-650 turbos with 66mm compressors; air-to-air intercooler; TH-400 RMVB and transbrake; 10" stall (badly needs replacing); 10-bolt rear with Moser axles & 3.73 gears. Rear suspension is Cal-Trac bars with split mono leafs and Rancho adjustable shocks. Front subframe is by Martz and has coilover, tubular control arms, rack&pinnion, and Wilwood disc brakes.

Keep in mind this is a street car primarily, but the intention is to also knock down some quick ETs. Right now I am just running off the wastegate springs at 8-9 psi boost. Only real problem so far is that the 10" stall converter is now flashing to 5900 rpm. I plan to take it out this weekend to see what it will do with 26"x9" slicks, but I don't expect to maximize my ET until I get a tighter converter.

How about some ET guesses?

Here are some pictures to go along with the description:




and a quick video of a 2nd-to-3rd gear pull:
 
See less See more
1 2
#5 ·
Nice build. A friend of mine put an LS in a PTCruizer. One 98mm turbo, turbo 400 and Dana, 10.5 tire, street legal. Took it to Pinks in Fl a couple years ago. He went 9.07 at 158mph, and a poochy 1.50 sixty foot time. It got small in a hurry. My guess with yours would be around the same if it hooks up. The one problem I see with yours is that you don't have a cage in the car. Whatever track you go to, if it's faster than 11.49 you'll need at least a roll bar to run to 10.00 and a cage if it's faster than 9.99. Be careful. Oh, by the way, he went through a lot of parts to get to that 9.07 and make it bulletproof. So I hope whoever built it knew what they were doing. Have fun and be safe. Keep us posted. Dave
 
#8 · (Edited)
...Be careful.
Some good advice. I do agree that I'll need to upgrade my 6-point roll bar soon.


..So I hope whoever built it knew what they were doing. Have fun and be safe. Keep us posted. Dave
I can't blame anyone else except myself for that. Built the engine, wiring harness, turbo plumbing, and ECM tuning. I paid for a front end alignment though...Here is a picture of my favorite way to spend a Saturday afternoon. Firing up a new build, laptop hooked up, working on the tune, and sipping a cold Diet Sundrop. That was a fine afternoon indeed:


Here is a shot of my tubing cut-off bin after the plumbing was finished...


Scott - I like your ET predictions. A lot will depend on what kind of sixty foot times I can get out of it with the lack of a boost controller and the loose stall. But I do like the sound of working my way into the 5's with a new stall and some R&D on power management.

Jason - you speak good advice on the fuel. While I have made several short pulls on the street with good AFR and zero knock , I do recognize it can be a different story under full power for the 1/8 mile. I'll ease into the WOT and closely monitor the AFR, timing and plugs. I really appreciate the advice from you guys that already have experience with tuning boosted engines and running fast. My biggest accomplishment this weekend will be to make some test passes and drive it back home.
 
#6 ·
Do yourself a favor and have it ran on a chassis dyno !!!! i just built a wicked 406 with a vortech v-7 ...only 7 psi boost ...30 degrees total timing ...and melted 3 pistons on my FIRST PASS :eek:... I THOUGHT my fuel system was OK ...HELL it was fine for my 737hp bigblock ....JUST not enough for the blown smallblock ... it ran out of fuel in second gear ,,and melted down ... still went 6.70 coasting 1/3 the track though !
 
#7 ·
Nice car indeed! Looks like it could be a real sleeper.. But I agree with the last post and I'm a true believer in the chassis dyno. Good luck and keep us posted

mid to high 5's is my guess
 
#10 ·
Nice job on the project and it's gotta feel good to see it back on the ground. No ET predictions here, there are WAY too many variables so are pretty much a waste of time. In most every instance they set people up for disappointment. Take it out, don't worry about ET's and most importantly, have fun with it.
 
#11 ·
Scott - I like your ET predictions. A lot will depend on what kind of sixty foot times I can get out of it with the lack of a boost controller and the loose stall. But I do like the sound of working my way into the 5's with a new stall and some R&D on power management.

I have ran 5.40's with twin 66's blow-thru carb on 357 cubic inches running on E85 with an air to air intercooler and 20 pounds of boost. Sixty footing in low 1.20's with a best of 1.18.

On 10 pounds the car would 6.10's. Good luck and keep us posted. I know you will run easy 5's when we get everything worked outed and increase the boost.
 
#12 · (Edited)
Well said Mike, and I appreciate you taking the time to give advice. I'm really just looking for some baseline tuning information and see how the chassis reacts, and just get some seat time with the new configuration. First couple of passes will be partial for sure.

71 Chevy - I let Shaun at Virginia Speed pick out the turbo grind cam for me. It is a reverse split with mid 230s intake and right at 230° exhaust duration @ .050" with .610" lift and 115° LSA. This profile gives 0° overlap at .050" lift which I suppose helps spool the turbos. Side benefit is lots of vacuum at idle for great street driving characteristics. On the shift point - I'm thinking around 6,500 to 6,700 rpm. The short block is strong enough but I don't think the cam profile will pull higher than that.

Weather isn't looking promising for test & tune tomorrow. If I get rained out then I'll probably spend the afternoon pulling the torque converter out and just move on.

By the way, a good friend of mine is plodding along in the middle of building his '67 Camaro into a twin turbo SBC Pro Turing machine. The project has idled for several months... until last weekend when I took him for a ride. He called this morning to ask me about places to order mandrel bends, and air filters. My mission was accomplished to re-motivate him. That's also a strong reason I post on these forums. To get motivation from other people's projects and learn.

Scott - you make it almost sound easy to break into the 5s... but we all know it takes a well thought out package to achieve. Thanks for the encouragement though. Sounds like you have already accomplished some amazing performance.
 
#13 ·
Easy?! Never! However it was fox chassis:D on 26x8.5 slick.

It takes a complete package. You have the power to get there, soon you will have to learn how to manage it. That is where the fun is for me, tweaking.

It is a close friends car and a motor I built. Stock block with scat crank and rods along with SRP pistons. Nothing special. Ran it hard for a few years in local 275/8.5 tire classes and eventually cracked the stock block after a year running 20+ pounds of boost.

Assembling a little M with more cubes and better heads. Shooting low 5's. Time will tell.
 
#14 ·
Well, I let a little rain keep me at home today. I'll just take the opportunity to order a new stall converter and make sure I am fully ready for the first track visit. I spent the afternoon today cleaning up some extra parts to put up for sale and raise some capital for the converter purchase.
 
#18 ·
I don't think the center caps would clear the 3" studs....

Over the past couple of weeks I upgraded the stall converter to a 9½" PTC race converter. Much better than the light weight 10" street version. So last Sunday I drove out to the track only to find they were closed due to wind. Yesterday I drove the Nova the 50 miles to work. Just before leaving for the weekend, I took a co-worker for a test drive. He ended up towing me back home after I popped a couple teeth off the pinion gear. :rolleyes:

So my plan is to replace the ring/pinion in my 8½" 10-bolt and then start saving up for a bullet proof differential. Time to start chasing the "weak link".
 
#24 ·
...Definitely don't jab the loud peddle going around a corner unless you want to go back the way you came.:no:
That's funny... So the 10-bolt housing is adequate strength wise for 1.3 second 60' times and upper 5 second 1/8 mile performance? Sounds like RadialNova's recipe would be my most affordable option to eliminate c-clips, upgrade the stock posi, and increase axle size.
 
#27 ·
RadialNova has a wicked SBC for sure!

Well, a friend on a local car forum (and this forum too) offered to sell me his 12-bolt from his 72 Nova. He has already built it with a Strange 33-spline spool, Moser axles, c-clip eliminators, and Richmond 4.56 gears. While it was briefly installed in his 72 he never drove it. Now that his build has escalated he has moved on to a 4-link setup and new differential. I should have the "new" 12-bolt later this week and then work on swapping those 4.56 gears (along with the 4-series spool) for some 3.08 gears and 3-series spool that will work better with my turbo engine. So it looks like I'll get a good opportunity to add strength for not too much money, and get this thing back on the road soon. Just maybe I'll still be able to get an 1/8 mile time before the track closes.
 
#30 ·
Time passes... 4 months later:

I love it how a forum thread will just sit there and wait for you to earn some money, collect some parts, crank on some wrenches, and report back later. So here is my March 1 update.
I bought a 12-bolt housing with 33-spline Moser axles, c-clip eliminators, 4.56 gears and a 4-series spool from John (member here). From the advice in this thread I decided to install the 12-bolt as purchased to evaluate the characteristics of a spool driven on the street. I knew the 4.56 gears wouldn't stay long - they are crazy in a street car. My experience with the spool was more positive than negative. It is pretty un-noticeable while cruising. About the only time I feel it is maneuvering in my driveway or parking. It does increase the turning radius, and it does make it more difficult to roll the car with the steering turned. But for the cost and reliability, a spool can't be matched.
So this past weekend a friend helped me swap the 4.56 gears and 4-series spool in favor of 3.08 gears and 3-series spool. I also added a cast aluminum cover/girdle. Now with my 28" tall street tires it cruises 2,300 rpm at 55 mph. the car is much more enjoyable to drive than either the 3.73 or 4.56 gears.


I also recently installed a boost controller that is time based so I can progressively bring on power as my small tires can handle it.


Huntsville Dragway will open up next weekend (depending on weather) so my next update with actual performance numbers should be coming fairly soon.

I want to thank the many people who gave opinions, advice, and personal experiences in this thread. As you can tell, you were instrumental in helping me through the rear differential decision process. Also thanks to John for selling me his "cast off" 12-bolt assembly.
 
#32 ·
After some transmission problems I have finally been able to make some decent runs at the 1/8 mile. I'm still working on the chassis adjustment and getting my 60 foot times to improve. I made 4 passes last Friday night, progressively adding more boost and small shock adjustments. Sixty times went 1.50 then 1.48, 1.46 and 1.459. So my shock adjustments firmer in rear and a little tighter in front appeared to help.
ETs were 6.33 @ 112.5; 6.22 @ 115.6; 6.11 @ 117.3; and 6.12 @ 117.2

Unfortunately the last pass I picked up some false knock before even leaving the line and the ECM pulled 3° advance out for the entire pass. Who knows if that could have been my elusive 5.99 number... These were all made with 93 octane pumpgas, a maximum of 15 psi boost, and I drove to/from the track without any problems all night. Had a bunch of friends there and was just a really good night of racing. Each pass, until the 4th, was my new personal best.



This week I am disassembling the rear suspension to verify I don't have any binding. Then I will put it back together with the Cal Trac bars in the upper hole to hit the tires a little harder. From the video it looks like the front end is coming up too quickly and the rear doesn't have much separation. Certainly plenty of room for improvement in the 1.45 sixty foot times.
 
#33 · (Edited)
It's been a while since I visited the Drag Racing SNS page. My '69 Nova has been down for the better part of 3 years while I did a LSX conversion, front subframe upgrade, and twin turbo installation. Over the past couple of weeks I finally got it back on the ground and logging some street miles. I plan to re-introduce it to the local 1/8 mile dragstrip this weekend for some test passes.

A quick run down of the drivetrain: 408 LS iron block (based on a 6.0 truck engine); 4" Callies crank; 6.125" Callies rods; Wiesco pistons; main&head studs; AFR-225 CNC ported heads; Victor Jr; 4150 Accufab throttle body; 80 #/hr injectors; GM ECM & harness modified and tuned by me using HP Tuners; twin Turbonetics GTK-650 turbos with 66mm compressors; air-to-air intercooler; TH-400 RMVB and transbrake; 10" stall (badly needs replacing); 10-bolt rear with Moser axles & 3.73 gears. Rear suspension is Cal-Trac bars with split mono leafs and Rancho adjustable shocks. Front subframe is by Martz and has coilover, tubular control arms, rack&pinnion, and Wilwood disc brakes.

Keep in mind this is a street car primarily, but the intention is to also knock down some quick ETs. Right now I am just running off the wastegate springs at 8-9 psi boost. Only real problem so far is that the 10" stall converter is now flashing to 5900 rpm. I plan to take it out this weekend to see what it will do with 26"x9" slicks, but I don't expect to maximize my ET until I get a tighter converter.

How about some ET guesses?

Here are some pictures to go along with the description:




and a quick video of a 2nd-to-3rd gear pull:
http://www.youtube.com/watch?v=CJnAbmC0NTU&feature=g-all-u
Sorry I can't tell from the pics but do you have a motor plate?
I'm enjoying your build. I'm glad you upgraded the rear end.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top