Transmission Cooler Recommendation.

Discussion in 'The "Juice Box"' started by LARRY70GS, Jul 28, 2015.

  1. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    Next month, I'll be installing a fixed pitch 400 along with a 10" converter I got from Ultimate Converters. I'd like to install a good free flowing transmission cooler and plumb it with push lok hose through the frame. With that in mind, does anyone make a transmission cooler with AN fittings? I'd like to use as big a line as possible, at least -6, maybe -8AN. I know a restricted cooler circuit is one of the ways to push the crank forward, so I want to make sure I have a nice free flowing set up. My current cooler is a simple tube/fin cooler that I mounted directly behind the grill.
  2. Ttype455

    Ttype455 Well-Known Member

  3. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

  4. Daves69

    Daves69 Too many cars too work on


    I can get you some power steering coolers off a Volvo truck as seen in the bottom of this picture. Aluminum tubing with fins attached.
    All it would cost you is shipping.

  5. sailbrd

    sailbrd Well-Known Member

    I use one off of a Ford Ranger. Get them for $10 at a junk yard and usual OEM quality. Mounted nicely in front of intercooler on passenger side.
  6. gusszgs

    gusszgs Well-Known Member

    Your tube and fin will give the least amount of pressure rise.
  7. hugger

    hugger Well-Known Member

    Seatrab or Griffin makes some really nice coolers, Ive ran several of the BanM "super coolers they come with NPT female ports making plumbing easy to as one wishes
  8. Ken Warner

    Ken Warner Stand-up Philosopher

    Larry, I used the -6 version of the Derale coolers linked above from Summit. Amazon was a few dollars cheaper with no sales tax a few months ago but it looks like the price is a wash now. Not sure where the guy above got info about tube and fin coolers having least pressure rise, that is counter to pretty much everything I read when I was researching these. Additionally the tube and fin are the easiest to damage and the least efficient. They are cheaper though! Besides Amazon try looking around at for some additional info on trans coolers and people's experiences.

    Please note I'm running one of Extreme Automatics 9.5in lockup converters that stalls around 2700-2800rpm. Cooler was installed just prior my drive to Norwalk this year. If you are interested I can attach a couple pics of my install tomorrow just let me know. Anyway, in the interest of saving myself a bunch of time typing I'm just going to paste in the bulk of an email I traded with Jim W regarding my experience with the Derale cooler below.

    Jim, I put the Extreme Automatics Stage 3 TH2004R in the GS about a month ago. No problems with performance or behavior but I got curious about temps when I needed to tighten up the speedo cable after a short drive and the trans was FREAKIN HOT!... So, I installed a temp gauge in the cooler return where it comes it at the side of the transmission. Driving around town and flashing the converter from stops eventually caused temps to peak in the 210F range. Regular cruising was in the 190F range, highway driving with converter locked allowed temps to quickly drop back into the 160F zone. So, I got a stacked plate Derale cooler rated for 32K BTU and plumbed it in series with the cooler in the aluminum radiator. FREAKIN' WOW!!! what a difference.... Trans struggles to get over 180 with lots of converter flashes. Regular driving causes it to settle right around 165F and highway driving with lockup engaged now nets under 150F on the autometer trans temp gauge. In addition to the happier trans I know my water temps normally would have been up around (or slightly over) 200F on the drive to/from Norwalk and they never went over 2 needle widths above 180F mark!!!
    Last edited: Jul 29, 2015
  9. gsx678

    gsx678 Well-Known Member

    TCI also make coolers with fittings
  10. gusszgs

    gusszgs Well-Known Member

    Ken, my bad I got the terminology wrong. I meant to say "plate and fin" not tube and fin. Here's where I read this
  11. Ken Warner

    Ken Warner Stand-up Philosopher

    No problem, thanks for not taking it as some sort of personal attack like a lot of people on here trend to do when you catch an "oopsie".

    From my reading there is tube and fin, plate and fin and finally stacked plate design coolers. Their efficiency and price go up as the size goes down as well. The stacked plate style are really sturdy to boot.
  12. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    My main concern is not pushing my crank from too much internal converter/cooler pressure. I remember Yardley going through a few transmissions with a won't shift problem that turned out to be a cooler clog or restriction. Pretty sure it was a B&M cooler. Naturally, I'd like efficiency also. So what is the safest option?
  13. Ken Warner

    Ken Warner Stand-up Philosopher

    Most of the plate and fin and stacked plate type coolers work like a cross flow radiator (parallel circuit in electrical speak) so you would need a LOT of crap to get in there to actually cause a restriction. The tube and fin units though tend to me more like a race track through fins (series circuit) so any restriction at any point affects you. The stacked plate style tend to be thicker but take up less space in the X-Y direction, so less blockage to airflow for the radiator. Something to keep in mind, some people recommended NOT installing them with the inlet/outlet pointing down (others say its fine). I can kind of see why as you might end up with a situation where it gets an air bubble locked into the upper passage but it seems unlikely. Didn't matter to me as I mounted mine with the inlet/outlet facing the passenger side.
  14. Jim Weise

    Jim Weise 1000+HP

    Hi Larry,

    Good to seeing your going in this direction, hope they have the right converter combo put together for you.

    As far as coolers go, stacked plate for sure..

    Line size?.. I did extensive study on this when designing my thru the frame trans line kits.. I used my 89 Suburban with VP TH400 that we used to tow my enclosed trailer.

    Because -4 line and steel fittings are so much more compact that the -6 stuff, I actually mounted both a pressure gauge in the trans line after the cooler (an early stacked plate one) and a trans temp gauge in the pan..

    One summer we used -6 lines, and I got very familiar with the pressures and temps in both just empty around town driving, as well as full load, hot summer day towing..

    The next year, I switched it to -4 lines.

    I noticed less than 10psi increase in pressure on average, but I also noticed consistently cooler trans temps. While it's true that the trans lines will most likely outflow any stacked plate cooler , in my case a mild line restriction actually help slow the fluid down, so more heat was extracted via the cooler.

    Pressure increase was inconsequential.. max allowable pressures in the cooler lines are often give at 60-75psi, you should find that you see about 25psi in drive, going down the road in high gear. Detent pressures will be around 35-40 psi (Low 1 and 2).

    If your really worried about it, simply add a zero to 100 psi pressure gauge to your gauge package there, and monitor cooler line pressure..

    Much more concerning than anything cooler related is that if the trans was modified at all for increased line pressure, the converter feed needs to be restricted in the pump. The feed to the converter is tapped and a plug is installed, with an 1/8 hole drilled in it..

    And lastly, mechanical issues... Clearance between the crank to flexplate bolts and the converter cover is critical. needs to be at least a 1/4"... more is better. The flexplate will flex forward under power, and if the bolts contact the converter cover, it's all over...

    This is actually pretty rare, most quality 245MM and 258MM converters in the aftermarket will have a forged or billet cover, those provide considerable bolt clearance.

    I have run into one converter that cause an issue, it was a 245MM unit that just had tabs welded on it for mounting..

    Good luck, hope that converter is about 3500-3800 stall with stickies at the track.. that should drop your 60' time and resulting ET dramatically.

  15. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    Hi Jim,
    All the racers in the N.E gang raved about Lenny at Ultimate Converter Concepts, so much so that I went that way.

    I sent him everything I had on the car and engine. Dyno sheets, all the engine specs, and gearing. I have weighed the car for the last 2 visits to Cecil and it has been consistently a bit over 4000 lbs (4025) with nothing in the trunk, half a tank of gas, and me (165 lbs). I told him it would likely weigh in at 4200 lbs once I put the A/C back in and put my stuff back in the trunk.:grin: He sent me a 258mm Northstar core converter. Told me it should stall at 34-3600 RPM and it should work with the GV. The Csordas's say Lenny gets it right the first time, every time, so we will see. I'm expecting to pick up in the first eighth of a mile because the car is consistently picking up 22-23 MPH from the eighth to the end of the quarter mile, so it's running right.

    After reading about the thrust bearing issues, I am understandably nervous about this change, but I have to see what it gets me, because I think the SP is slowing me down at this point. I had Mark Deconti build me a 400. Mark has been doing transmissions for the club since before I was a member, so I trust him. Nevertheless, I will e-mail him about the line pressure/converter feed and see what he did. After reading this article on thrust bearing failure, I noted one of the things mentioned was to use bigger lines.

    I was going to use -8AN push lok stuff, but I will go -6AN if you think it will be better. Will this cooler work for me? Seems to be the right size to mount right behind my grill where my current cooler is.


    Attached Files:

    Last edited: Jul 30, 2015
  16. Jim Weise

    Jim Weise 1000+HP

    Ya, no problem Larry, if it ends up there, it will be great..

    Just make sure you have at least 1/4 inch between the cover of the converter and the flexplate to crank bolts. Use the ARP thin 12 point bolts if your not doing that already.. and don't be afraid to add a machined washer or two between the flexplate and converter.

    The early SFI flex-plates did not have the offset in them, like the factory.. the offset is away from the crank, which increases converter to crank clearance. So we have to make up for that with shimming. The latest one from PEP that I am now using, does have some offset in it.

    I can't tell from the pictures for sure, It should be ok, but you might want to lay a stock flexpate on that converter, and see where that step in the cover comes out. If that step is anywhere near the flexplate /crank bolt circle, it will complicate the issue.

    Be aware of the issue.. and avoid it, and all will be good.

    That cooler should be just fine, and -6 lines are more than big enough.

  17. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    I've got the ARP bolts you recommended when we installed the motor. I'm sure they are the right ones.

    And how does this cooler look?
    Last edited: Jul 30, 2015
  18. bobc455

    bobc455 Well-Known Member

    Sorry to sound ignorant, but this is the first time I've heard of this. Is there a picture or something to help explain? I am reading the words and the concept just isn't sinking in for me...


    -Bob Cunningham
  19. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    I have a stock reproduction TA flexplate, so I bolted it up and measured. As near as I can measure, I have about 5/8" from the underside of the flexplate down to the front cover of the converter. I am using the flexplate to crank ARP bolts you sent me, these,

    I see the offset you mention, and realize the SFI flexplate on my engine has none. I took some pictures so you can take a look, and for Bob:TU:




  20. Jim Weise

    Jim Weise 1000+HP

    You should be good Larry, the cover should clear.. I would put a nice hardened large diameter 1/8 inch thick 7/16 washer between the the converter and flexplate, this will make up for the lack of offset bevel in the SFI plate.

    Converter builders don't typically have any idea what a 455 Buick SFI flexplate looks like, and they build the converter to a "spec height".


    The flexplate, under power, will flex toward the engine.. if the cover of the converter touches the flexplate bolts, it will take the thrust out.

    Here is a youtube video of flexplate movement.

    I diagnosed and repaired this situation here with a 470 in a 70 GS I had supplied an engine for last year..

    You can see the imprints of the flexplate bolts on the converter cover below. This is a low cost TCI unit without the Forged/billet cover, it was sold as a ("light duty, low stall unit for cars under 3000lbs") and had no business being in a 3800 lbs/560HP GS.


    Note the bolt marks on the converter cover.. this is why I wanted Larry to look and see where the raised area on his converter cover lined up, in relation to the flexplate to crank bolts. This one had insufficient converter cover to flexplate bolt clearance.. it would have worked with another .100 or so of shim between the flexplate and the converter. There was plenty of room to shim it, and exactly what I did to temporarily eliminate the issue, while testing.

    I sent the above converter off and had the correct cover put on it.. which brought that unit's cost up to what my stuff costs..

    This is what needs to be avoided at all costs.

    The improper installation of the incorrect converter for the application, cost my customer thousands of dollars.. and 3 months lost with the car ( the time it took me to build a test engine and install it in his car, locate the problem, and repair his 470, and put it all back together).


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