Turbocharged your Nailhead tips

Discussion in ''Da Nailhead' started by 66larkgs, Jul 13, 2015.

  1. 66larkgs

    66larkgs paul 66gs turbo nailhead

    i have been getting some PM's about turbocharging Nailheads so I wanted to post up some hopefully helpful tips that i wished i would have know.

    #1 . I made a set of turbo headers with the turbo mounted on the pass side behing the headlight. The Cross over for the exhaust goes infront of the engine and i used pieces from the ford fox body single turbo setup. The ford 302 port spacing is the same as a buick nailhead but the nailhead flange is 4 inches longer in between port 2 and 3. u can use a ford 302 header and lengthen it 4 inches in the middle and weld a buick flange on it. With forward facing headers you will have to be careful of the steering shaft interference and the front accessory drive system. I had to fabricate a serpentine belt setup to keep everything tight. I used a Buick 3.8 crank pulley and drilled it to fit my balancer. I used a gm type 2 power steering pump and pulley, March water pump pulley, and a GM 1 wire alt i used also. I had to switch to a electric fan.
    For a twin turbo setup i would use factory manifolds, cut and plate the back and open up the fronts and weld a front v band flange. i have been plaing with stock cast manifolds and once preheated to 400* degrees you can weld a v band flange to them with no problems and let cool in either the oven or in sand box.

    I run a Borg Warner S475 turbo from Forced Induction. It is a 75mm turbo with a 91 exhaust wheel and a 1:10 a/r housing . it is a little big and doesn't spool full spool until 3k. with the stock converter it sucked. PTC Built me a convertor for my th400 and really made a difference with it and it builds full boost a lot faster than ever before. I wouldn't mind running twin 60mm turbo's with small exhaust housing. I tapped the valley pan and put a one way valve with a oil to air separator and it is welded to the airfilter housing so the turbo inlet pulls a vacuum on the crank case. The oil feed is fed off of the oil port near the oil filter housing and is a 1/4 line with no oil restrictor. The oil drain goes to the front of the oil pan and is a --12 an line. do not go to the back of the pan!! will cause pressure in the drain and cause oil to back feed and push by the seals in the turbo and it will smoke.

    Wastegate is a tial 44mm and could up it to a 60mm and i do run a Tial Blow of valve .

    i run a water/meth injection setup from AIS. I like a A/f ratio of 12:5 under full boost at wide open throttle. 13:8 under cruise.


    #2 Cooling system.. i cut and lowerd the radiator support and added a much larger alum rad and with a 195 thermostat it staies right at that. i do use water wetter and swear by it. I did have to modify the upper rad outlet on the radiator to angle and avoid the larger turbo housing i upgraded to.

    #3 Fuel and induction.. I Use a CSU blow thru carb and a EV carb Hat. Tuning is done with FAST 02 sensor monitoring system and a simple jet kit and air bleeds. Fuel pump is a aeromotive A1000 fuel pump and boost reference fuel regulator with -10an feed and return lines. The fuel regulator will add 1 psi of fuel pressure per every pound of boost . base setting is 6.5 psi. i purchase a robb mc fuel sender and had to modify it to. not happy with its quality and would do a sump on the pan or a baffled fuel cell. I had to extend the pickup by a foot in the tank because of hard. I was running a intercooler and found a leak in it and no longer do. I would rec intercooler with anything higher than 10psi boost.
    I run a msd 6btm box which will pull 1* of timing for every pound of boost. I run two light grey spring on my mech advance in my msd pro billet dist and no vaccum advance and a total of 32* with no boost and 20* timing at 12lbs boost.

    #4 engine mods.. I had JE machine me a set of 9:0:1 pistons. The motor was machined .038 over to accept a good total seal ring for turbo engines. think it is a nitrated steel. Comp Cams cut me a custom turbo grind. ARP main bolt, I did have an interference problem with one of the arp bolts to the oil pump housing and was advised from ARP to chaffer the bolt for clearance. I also used ARP rod bolts and Head studs. I run a stock fel-pro blue head gasket. Intake to heads and heads to headers where gasket matched and all chambers and runners where smoothed but not all hogged out. The intake manifold has had some work done to it on the Bridgeport and with the carb spacer it was machined to look more like a airgap intake.

    #5 Exhaust. I run a single 3" exhaust and used cooper permatex on all turbo t4 flanges and have had no leaks since. I do not run a muffler and the car is very quite and even passed the wife test on the highway where we can still talk with the windows down.

    Their is many things i am sure i am missing and didn't want to go into everything else.. ie suspension/transmission/rear axle and brakes but i will say it hauls ASS!!!
    I am looking to go back to the track again and have only been twice and never got a good run and didn't have the bugs worked out of it at the time.

    Their is a lot of pictures of the headers and just the whole build. This was my second turbo setup on this car and first was a rear turbo setup and didn't like it.
    feel free to ask any question.

    http://s917.photobucket.com/user/66larkgs/library/66 skylark turbo nailhead

    Paul
    66larkgs
    turbo 401 nailhead
     
    Last edited: Jul 13, 2015
    Donuts & Peelouts likes this.
  2. dual-quadism

    dual-quadism Black on Black

    Thank you for the tips! I have a recurring dream to turbo my 65 Riviera. Maybe do a rear mount since engine compartment is a bit tight. What are your chassis dyno #'s?
     
  3. custum65GS

    custum65GS Well-Known Member

    Thanks for the tips Paul!!!
    Lots of great info to keep in mind when building a turbo deal like you have!!!
    One day I will have a turbo engine,,,I've often thought of a belt driven supercharger also,,,but turbos just sound so cool!!
    The mid mount turbo deal didn't work too well?? Chris
     
  4. sriley531

    sriley531 Excommunicado

    Lots of good info there from a guy who's done it, great post Paul!

    PS, where were you this year?! Was waiting for you to roll into bpg/Norwalk!!
     
  5. 66larkgs

    66larkgs paul 66gs turbo nailhead

    Havent put it on the dyno yet but would love to put up big tq numbers. 700-800 with a shot of meth and 15psi would be nice. I run it at 10-12 psi depending on how hot it is out and not on meth. With the meth I can turn it up alittle. I have been working part time lately to save up for some parts but should really make a appointment at the local dyno to see what it is putting down. its a $100 a hour and would really rather go to the track and run it their. My track goal is 11:80s on street tires.

    The problem I had with the rear mount is the need to pump the oil back into the engine. I ran a turbowerx eva pump and I had a issue with the one way check valve on the turbo oil line and I didn't like how the turbo piping had to be run under the car. the other issue is you have to run a smaller turbo and exhaust housing to get it to spool quick but it limits your max output. the plus is you didn't have the heat of the turbo under your hood but the turbo also benefits from that heat to help spool time. tons of plus and minus and all matters power goals.
     
  6. 66larkgs

    66larkgs paul 66gs turbo nailhead

    I wanted to go but because it was a earlier and all the snow days because of the blizzards I was still teaching auto shop at the vocational school. I take a few days off for lake George Adirondack Nationals but would have to take four days off and couldn't do it with giving finals. I would love to make a trip up this month or next month and do some racing with some Buick guys somewhere. I don't mind road trips and love being around Buick guys.
    Last time you saw me we didn't even have the motor broken in from the rebuild. We drove 16 hours with a motor that was pissing oil and a new intercooler with a hole in it. Everyone was great lending us tools and feeding us beers in the parking lot of the hotel at 11:30 at night when we were working on it. Best people are Buick people!!! We have had some bad luck over the last 16 months. Had a bad torque convertor making noise that made me think it was a detonation, did circles chasing that.. Thanks John Everette. We split a bellhousing before that and starved the motor of oil from the old turbo setup. Hurt the main bearings. Motor was smoking like a bugger after the rebuild , thought it was the rings but had the turbo oil drain 1" too low.
    I just want to save some people some of the headaches I have had.. I guess lesson cost money and good lessons cost more.
    I would love to encourage or help some other to go the turbo route. I would love to get the nailhead some more attention that it deserves. I have a ls3 6.0 sitting their and would be easy to throw it in the car and make tons of power but I think it is more important to take the harder road and prove it can be done even thou their is going to be some downfalls.
     
  7. custum65GS

    custum65GS Well-Known Member

    Those LS engine do make gobs of power,,,guys on youtube like"sloppy mechanic" slamming turbos on junk yard engines and then hauling down the track in 10 seconds make it look so darn easy!!!
    I think what yourve done with your turbo build is awesome!!! Chris
     
  8. 64 wildcat conv

    64 wildcat conv Silver Level contributor

    It takes a lot of money and effort to do it right. I'd love to build a turbo nailhead like Buick was thinking of doing back in the day. Finding/making similar parts would be expensive even for me. I design turbos for Borgwarner in AVL, NC. My current project is the next DMAX for GM. This is what I'd love to see under my Wildcat's hood:
    turbo nail 01.jpg
    This set up supposedly made 700+ lb-feet of torque and broke the transmissions on the test stand, which killed the project, or so the story goes.
    I could likey fab the exhaust manifolds, inlet piping, and airbox. The turbo would have to be matched from an existing BW turbo (this one is from Garrett, I think). I could probably fab similar flanges to the turbine and compressor housings and maybe rapid prototype the compressor to intake maifold flange. The carbs look to be Carter side drafts. The bigger problem might be fitting it under the hood. It looks to be a little taller than my current Edelbrock 4bbl and low profile air cleaner which just clear. Possibly a period correct hood scoop and a heat shield to protect the paint would be in order.

    I've also considered a rear mounted turbo set up to keep the heat out back. This would keep the stock engine bay look except for the pipe coming up and connecting to the carb.
     
  9. Bib Overhalls

    Bib Overhalls Well-Known Member

    I was at Rad Rides by Troy (Trepanier) a couple of weeks ago and the CNC machinist showed me a Nailhead block girdle that they had coded up and whittled out for a customer's twin turbocharged 401/425. I don't know if they would make you one or how much it would cost but if you think you need to beef up your lower end giving them a call won't hurt.
     
    300sbb_overkill likes this.
  10. 66larkgs

    66larkgs paul 66gs turbo nailhead

    Thanks Bib for the heads up on the girdle. I will def try to get a hold of them and see what they could do. That twin turbo in the buick that rad rides built is unreal.. I was hoping to see it in person at sema and missed it but have read every article they wrote about it. i bet that car was north of 250k to build.
     
  11. sean Buick 76

    sean Buick 76 Buick Nut

    Any pics of that nail girdle
     
  12. 66larkgs

    66larkgs paul 66gs turbo nailhead

    Sean, I never saw a picture of the girdle. Would be pretty cool. Would mind building a windage tray for it to. Right now car is sitting in the garage and has been super reliable so it will not be comming apart until i break something.
     
  13. riv1964

    riv1964 Well-Known Member

  14. sean Buick 76

    sean Buick 76 Buick Nut

    No that’s cool I’m sure a girdle is not even needed for your application
     
  15. 87GN@Tahoe

    87GN@Tahoe Well-Known Member

    Looks like that crank is a custom piece too.
     
  16. bhambulldog

    bhambulldog 1955 76-RoadmasterRiviera

    this should be made a 'sticky'
     
  17. sailbrd

    sailbrd Well-Known Member

    Denny Manner said they could not do the turbo nailhead because it broke the tranny's! Too much torque (700 ft pounds.) Buick used a tiny turbo on the one they built. To those of you thinking about this I would suggest the following: 1. Fuel injection, they are now the same price as a CSU carb. 2. New tank with pump, you will need a new fuel system no mater what. 3. MSD 6530, because it is so easy to get a good timing curve with it. You can save money but using timing control from the FI though (save money... boosted Buick :D)
     
    300sbb_overkill likes this.
  18. telriv

    telriv Founders Club Member

    They broke DynaFlow's as the TH400's weren't out yet.
     
    300sbb_overkill likes this.
  19. 66larkgs

    66larkgs paul 66gs turbo nailhead

    Just a update.. car is still running great with the turbo setup. Been on for a few years now. Still more power left in it but I don't push it as hard as it could. Need to take a updated video
     
    Custom65GS likes this.
  20. Custom65GS

    Custom65GS Member

    This thing still hauling the mail??
     

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