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65 Mercury Comet turbo big block

Discussion in 'The Turbo "Builds" Board' started by captaingriffin, Feb 17, 2017.

  1. captaingriffin

    Jan 21, 2015
    Ive been working on this build for a year and a half now and wanted to share with everyone whats going on. Throughout this build I have learned a lot of new skills and theory about turbocharging and hope that it makes for a better overall end product for this project and new projects to come.
    So here we go, the car is a 1965 Mercury Comet 2 door sedan that originally had a 170 six cylinder and 3 speed. Plain car with little to no options but was in pretty decent shape with exception of rusted out trunk floor, rear quarters and other common areas on these things. I bought the car for no real reason about 7 years ago after I saw it pop up on craigslist for a deal, maybe $700 don't even remember how much. Thought id get around to messing with one day.
    Well that day came about 2 years ago I had just gotten rid of a s10 drag truck toy, also from craigslist, and wanted to build something more my style. I had lots of ford stuff laying around the shop and the plan was build a budget drag/street car with the stuff I had around or could buy for cheap off craigslist or ebay. Thats the plan at least!
    The goal for this car is to go mid low 6's in the 1/8, be streetable, and not break the bank! There's several local 1/8 mile tracks in my area we like to visit so thats going to be its main purpose. Id like to be able to drive to the track, race, and drive home. And who knows, maybe even some 1/4 mile tracks here and there. Hell Drag Week 2020 here I come LOL!

    Quick rundown on the specs'¦
    65 Comet 2 door sedan lightened about everywhere possible.
    BB ford 460: stock cast piston, car rods, stock crank, all stock fasteners, ported D3 iron heads with 3 angle stock sized valves, custom ground turbo flat tappet cam, eddy single plane. Engine was dated 71 and is out of a car. Was pulled from one of my other projects with another engine was built for it and has around ever since.
    C6 auto: Full roller bearing conversion, 5 clutches in all clutch packs, alto reds, extra wide band, E lever, R servo, updated sprag, TransGo stage 2 shift kit, all stock hard parts, custom 9.5' converter from R&R Converters spec'˜d for this car. Hurst promatic 2 shifter. Trans is out of a 71 police car.
    Axle: Narrowed 9 inch, spool, 31 spline axles. Currently has 4.10s, probably gonna change them out after I get it going.
    Induction/ignition: FiTech power adder 1200, Msd 6al.
    Turbo: Holset BHT3B from a 14L Cummins. Gonna keep the boost mild while I learn to tune this thing.
    Enough talk, heres some pictures of the build up to where it currently sits.

    12-1-17: Ignore the photobucket failed links. The actual pictures are there.
    6-14-19: Some how some of the pictures from the first post are missing. I replaced what I still had.

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    I built a tilt front end using most of the original sheet metal. The line in the back of the front fender is where it separates from the rest of the car when tilted forward.


    Hang on to those old water heaters, theyre handy in more ways than heating water LOL. Painting the bottom of the car here.

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    Axle width before.

    I used an old open carrier I had to use in straightening the tubes. By opening up the id of the carrier to the od of the stock 28 spline axle shafts, I was able to slide the stock long shaft through the center of the carrier to see if the tubes were bent and properly line up the bearing ends. Seemed to work pretty good! Especially for my first time ever narrowing an axle. I just couldn't see buying an expensive alignment bar and pucks to do one axle!

    Axle width after.

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    Rear brakes cleaned up. I threw in some wheel cylinders from an e250 van, they had a little larger bore. Should help hold boost at the line since I do not plan to use a trans brake.

    More to come...
    Last edited: Jun 14, 2019
  2. Twin Turbo Skylark

    Dec 16, 2009
    Very cool thanks for sharing! This should be cool! Are you leaving it patina or painting it??
  3. captaingriffin

    Jan 21, 2015
    Thanks! The patina is staying. Ive repainted the bottom, engine bay, and most of the interior though.
  4. Mnlx

    Sep 20, 2009
    Very cool car, and I love to see the ingenuity, but the water heater doesn't look safe at all..... Be safe.
  5. captaingriffin

    Jan 21, 2015
    Thanks, and I appreciate your concern! I too thought the same thing when we first got her in the air but believe it or not that thing was surprisingly stable. I try to work with safety on the mind at all times.

    After painting the bottom of the car I dropped it back down to my elevation, slid the axle into place, converted the front end to 5 lug, and bolted on the draglites pictured above. The car was finally rolling again! Oh and way earlier on I had swapped in a Mustang 2 front end with a manual rack. I rolled her back into the shop and started on the engine. Like I said earlier this engine was pulled from another one of my projects when I had decided to build another for that one. But thats another story! This baby is no diamond! Its a stock bore 460 with cast pistons and car rods. I had it zero decked by a local machine shop to improve quench. It also has a crack on the outside of the block just behind where the starter would go that I repaired with jb weld 13 years ago! Hopefully it will continue to hold up lol! All Im buying for it is new rings gapped for boost and all new bearings. Anyone want to place bets on how long she'll hold up under pressure haha?? Sorry for the large photos by the way, still trying to figure out resizing.


    Doing some debur and oil drain improvements.


    Installing cam bearings


    13 year old jb weld


    This was from cylinder one. Looks like a bb or something went through there at sometime. The combustion chamber showed similar markings too. It was like that when I first pulled this engine apart 13 years ago! This time around I tryed repairing it. I know I could just buy another one for cheap whats the fun in that!? So I cleaned it up, filled the little holes with weld and sanded it smooth. I think it came out pretty good considering it was the first time i ever welded aluminum. I tigged them up with some 6061 rod. Time will tell if it will hold up or even work at all.




    This piston may or may not have also gone in this engine. Apparently 429-460s are bad about breaking off the tabs on the piston skirts.


    Filled the short block with all the "good stuff"


    I contacted Randy at R.M. Competition about building me a cam for my car. Very knowledgeable and helpful man. Hes also competed in the Engine Masters Challenge held by HotRod Magazine. If youre looking for a nice cam for something look him up. Im hoping his talent will trickle down into this turd and make it shine lol. This is just a flat tappet cam. I dont plan on getting too wild with the rpms in this thing to try and keep it together. Thats enough for now, more to come later...
  6. flyinhillbilly

    May 8, 2006
    I love it. Looks like something I'd do.
  7. captaingriffin

    Jan 21, 2015
    On to the top end. I had a set d3ve iron heads laying around forever and decided to use them for this build. They have a 95cc chamber and 2.08 intake / 1.65 exhaust valves. Before I started working with them I tried to do as much research and digging around as I could on head porting and combustion chamber shape and design. I feel a lot of what it takes to making decent power comes to the heads so I tried to do the best I could with my abilities and budget would allow. I came across a guy over on 460forum who goes by TheMadPorter who has probably done more with these particular heads than anyone else. Big thanks to him!! Most of the work I did to them was in the exhaust ports as stock they are very restrictive but with some proper massaging of the bowl and short turn they can flow decent numbers for a factory old cast head. I cleaned up the bowls on the intake side too. In addition to the ports I smoothed the combustion chambers and unshrouded the valves a little. Ive messed with porting before but never touched combustion chambers so I hope what I did will make a difference for the good. With these heads and the dished pistons compression for this engine should come in at boost friendly 8.3:1.

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    Before I did anything to them... Forgot the take after shots :bang:

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    I did a 3 angle valve job too. I think they turned out well! I did not cut 3 angles on the seats.

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    My fancy valve spring scale, measuring for seat pressures and open pressures. This actually worked pretty good. I also found a set of old secondary springs from a comp cams valve spring set. They fit like a glove inside my original valve springs and on the seats and retainers. Them combined with my original valve springs put me pretty much exactly where I needed to be on pressures without coil bind. Will see how this holds up down the road.
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    Going together with it, using the stock head bolts. These things have beefy 9/16 head bolts that are torqued to 140 ft lbs!

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    Added some big breathers to the stock valve covers and used them as a test bed for powder coating. This is supposed to be a wrinkle finish black. For the first time ever power coating I think they turned out decent.

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    All together. Scored this eddy single plane in an ebay auction. I wanted to retain pcv so since I turned the original location on the valve cover into a new breather I relocated it to behind the back of the intake drawing from the valley. Hoping it doesn't draw oil into the intake from here. If it doesn't work out ill just plug it off and go a different route. More to come later..
    Last edited: Dec 1, 2017
  8. 70bbftorino

    Feb 18, 2015
    keep up the progress reports.....i got a 460 in my Torino and am always heading a million directions with build
  9. BlownShovel

    Apr 29, 2003
    getting there - keep up the progress - THe DIY PC turned out decent. biggest problem I have had is contaminants causing issues - clean things like crazy, spray and bake. good job
  10. Billy L

    Jan 20, 2014
    Love the car man, looking good.. keep it up.
  11. captaingriffin

    Jan 21, 2015
    Appreciate the compliments guys. Ive since powder coated several more things and am starting to get a feeling for it. My biggest problem now is getting even coverage. Just something to work towards.
  12. captaingriffin

    Jan 21, 2015
    Once I finished the engine I started to work on an oil pan that would clear the mustang 2 cross member and allow the engine to sit nice and low. I had previously picked up a spare 460 off a guy at work for cheap just to have for parts or as an emergency backup. It was out of van so it had this nice mid sump oil pan and truck style oil pickup I could use in my build. I cut the pan up and turned it into a rear sump. It now clears everything very well and will hopefully work out well. It holds about 6 quarts. Here are some of the stages I went through.

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    Fully tig welded. I bought an AHP Alpha Tig 200 and this was my first project with it. It took some time getting the settings and technique right but I think it turned out good and it doesn't leak! Tig defiantly has a learning curve but im glad I picked it up. Ive since tuned in the skill a little but have got a lot left to figure out. Always learning.

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    Bolted up the pan to the spare engine and c6 I pick up off the list and slid to combo into the car to make up motor mounts and trans mount. This is as low and as far back as I could place the engine without heavy modification to the firewall. I did have to modify the tunnel a little to clear the big c6 bell housing. More to come later..
    Last edited: Dec 1, 2017
  13. Turbo Drag Radial

    Mar 4, 2007
    digging the build. Keep the updates rolling!!!!
  14. afterfire

    Dec 10, 2012
    This is cool. I have a buddy that uses wheels to prop his derby trucks on the side so he can work on the bottom. Never had an issue thanks to some form of a miracle.
  15. vinces427bb

    Sep 30, 2013
    love the car
    its gonna be cool
  16. captaingriffin

    Jan 21, 2015
    Thanks for the compliments guys! Now that the engine and transmission was positioned and mounts were made I started working on turbo location/mounting and the hot side. I am far from an expert when it comes to reading compressor maps and determining proper turbo sizes and specs and ar’s and millimeters and and and…. So after reading for hours and doing what seemed like endless research I had originally planned on just breaking down and buying a tried and true s475 but really didn't want to drop the money on a new turbo for this build. While doing a daily craigslist search I came across this Holset BHT3B for $150 which seemed tempting. I did some research on said turbo and figured for the price I think it would out ok. Called the guy up and we made a deal. I actually came home with it for $75! I think the guy was real tired of it sitting around lol. This particular bht3b has the 32cm exhaust housing which I think will be good for as many cubes as I have, will see for sure once its up and running. I know there are a couple draw backs about these turbos being they are reverse rotation and the compressor is a little small for this engine at 73mm. But for the price I pulled the trigger.

    Couple specs on the Holset bht3b:
    Compressor- 73.4mm inducer 109mm exducer
    Turbine- 97mm inducer 86mm exducer
    32cm exhaust housing. Not sure what that works out to in ar? 1.3ish?
    Flange is unique, close to t6 but slightly larger
    5.5” inlet, 5” exhaust

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    This thing is heavy! ID tag dates it 1989 and from a 14L Cummins. My other turbo project sitting behind.

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    Mount made and turbo bolted up for fitting.

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    Using modified passenger car manifolds. These things were hard to weld! Joined them with some 309 stainless rod. This is the now passenger side manifold.

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    Drivers side manifold and starting to run the hotside over. Tubing and vbands came from Columbia River. All 2.25" from manifold exit to turbo flange.

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    I made the flange from some 1/2 plate I had laying around. Its ported to match the turbine housing for a smooth transition.

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    The merge. Using one 60mm wastegate to control boost. Both wastegate and bov are the vsracing house brand.

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    Not pictured but I later added a strap about 5" below the flange to each side of the tubes to help eliminate expansion and contraction stresses on the wastegate tubes.

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    Each tube from the merge to the wastegate is 1.5". More to come..
    vinces427bb likes this.
  17. captaingriffin

    Jan 21, 2015
    Continuing on. Now that the hotside and most of the plumbing was done I started working on a cooling system. I work with a guy who used to scrap cars for a living and he had a shed filled with old radiators I had access to dig around in. I wound up finding one that was out of a Nissan Altima with dual two speed fans and a shroud. It fits perfectly in front of everything and should be easy to replace should I need to from a parts store. Im a little concerned it wont be enough to keep the engine cool but will see. It had some things going for it so I choose to go with it. Aluminum high density core, light weight, already has the dual fans, and the best part FREE. Core size is something like 26x19 I think?

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    I built a simple radiator support out of some 3/16 wire. It works very well and is very light. Also mounted the trans cooler to it. Cooler is from a Ford Focus.

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    Can also see the vsracing 60mm gate here and dump tube routing.

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    After the cooling system was mostly addressed I took it all apart and started building the c6.

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    I fully converted it to roller bearing. Cutting a pocket here to accept a bearing.

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    Going through the valve body. I put a transgo stage 2 kit in.

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    Finished product. Using the stock pan for now. I added a drain/temp sensor location to keep an eye on temps. Also powder coated in wrinkle black.
  18. captaingriffin

    Jan 21, 2015
    Moving along. After finishing up the transmission I put in an order with r&r converters for a torque converter built to spec for this car. Greg and his son there are very knowledgeable and helpful people and they recommended a 9 1/2" billet converter with an HD sprag and whatever else he said it needed. Fully brazed and the works. I know the build is a budget build but I felt this should be something worth spending a little extra on. I shopped around a little before going with them and for a custom converter I dont think you can beat their price. The downfall was they were covered with work, good for them but put me waiting 3 months. No problem I just put the drive-train aside and started working all the other things that needed to be done until it was ready. Like painting!

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    To my surprise this thing had hardly any shaft play. I have no clue what the history of it is or why it was original pulled but if I had to guess maybe it was due to the compressor wheel, the thing was trashed. I replaced it with with another regular cast wheel off ebay. It was also very sludged up and full of carbon on the center section. I cleaned it up real good, replace a cut oring and the wheel and slapped it back together for more abuse.

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    Wrapped the hotside and most of the downpipe

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    My buddy grabbed this shot of me welding on the remote oil filter mount

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    Going through a starter for this thing

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    Finished up the rear suspension with the shock mounts. The car is set up with ladder bars, diagonal link, and the stock leafs. I just threw some shocks in there I had laying around for now. Anyone got suggestions on real drag shocks for the future?
    Last edited: Dec 1, 2017
  19. 1966Mustang

    Sep 15, 2015
    Your moving right along on this build! Narrowing the rear end went pretty smooth for you then?
  20. captaingriffin

    Jan 21, 2015
    Its coming along but cant exactly take the credit for quick work lol. These photos were collected over a almost 2 year span. I just recently created this build thread. Ive almost caught up with myself though so the updates will be less productive looking, less photos haha. But yea the axle build went together pretty smooth Id say.
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