Oil temps without hoover bit

[Richierich56]

I'm trying to rectify a slight hot running issue on my Oval and wondered if anyone had any idea how running without the hoover bit on the doghouse cooler tin and having no foam tape on the cooler can affect oil temperatures?

10 degree hotter without or would it not make that much difference?

On a run my oil temps (have a save my bug dipstick in it) get to 235°f after about 40 miles. Timing is at 30° advance at 3,000. Have tried it at 28, 29 etc with no difference. Motor has done about 650 miles now.

One thing - when I've driven it at night when the ambient temps are a little cooler, I don't seem to have these issues.

Running an early doghouse fanshroud/cooler BUT the shroud is not a genuine VW one and on further investigation the hoover bit was not complete and there is no sealing tape on the cooler. Could this be the crux of the issue?

Have run decklid standoffs at bottom with no apparent change - top seems to help but not enough. Decklid is not vented.

2276 / Aluminium case / 10:1 comp / 44x37.5 heads / 48ida's
10w30 mineral oil with ZDDP (was running 20w50 so changed to this 10w30)
Full flow wih ext filter, deep sump - no external oil cooler
Jetting all good
Valves adjusted to loose zero at cold -chromo pushrods
Stock gear ratios - stock sized pulleys - 205/65/15 rear tyes

Anyone any ideas or am I going to have to give in and run an external cooler?

[andrewlandon67]

I'd try running your valves to .002 inch cold and make sure all of the ducting for hot air out of the oil cooler is complete. Also, out of curiosity, what kind of fuel are you running? 10:1 compression sounds rather high for any sort of conventional street gas, most people I know here at 5200 feet elevation say the highest one should run is 9.5:1, and the lower your elevation is, the lower your compression needs to be to run pump gas.

[neil68]

I live at 3,600 ft elevation and run 34 degrees advance and 94 octane (98 RON) and 10.7:1 CR.  I have the later doghouse shroud with Hoover bit and FI venturi ring and the engine stays under 210 F. unless I run without the fan belt (hot lapping at the drag strip).  I think you should add the foam to the oil cooler, plus the Hoover bit, but don't have data on how that would affect cooling.

Oil is 10W30 synthetic and I have a solid deck lid (1968) but it's open at the top (Hoodlum extension) to clear the Weber IDAs and provide more air (I'm not a fan of opening the bottom of the deck lid, as it just sucks up hot air in stop & go city traffic).

Maybe experiment with the ignition advance?

[Richierich56]

Andrew - I run Shell V Power Nitro which is (apparently) 99 octane. I'm confident it's not the fuel that's the issue. All my ducting from the dog house cooler is there and sealed.

Neil - I think my motor is a similar spec to yours. You run 34 advance? I may ty and see what effect a little more advance has.

I ran with the top of the lid open but here the changeable weather can make that difficult.

Out of curiosity - you run the later wide fan shroud? What's the fit like with 48's? I have a genuine late doghouse one but thought there would be clearance issues with my 48's. Could you post a pic up of your motor on here for me?

I am beginning to wonder if my non-genuine shroud may be the problem

[Torben Alstrup]

On such an engine you need ALL the factory bits´npieces in the cooling system installed. The engine needs air, meaning a slotted decklid or cnvertible or thye likes. Ignition timing and precision  is crutial as of course the fuel mix. Down the road it should not run much warmer than a stock engine, but if you step on its tail it will build up heat, fast.
Correct oil pressure reduction springs in relation to both oil viscosity and oil pump size along with choice of actual oil brand can soon make a 10 - 20 degree difference. - Youre not by any chance running a 30 mm oil pump ?

Personally I would never run without a thermostatic controlled external cooler on such an engine. The "window of power" is just too small for me.
T

[Richierich56]

Thanks Torben. No not a 30mm - I run a 26mm Shadek pump.
I think I'm going to fit my genuine late doghouse shroud and see if that makes any difference.

[Martin S.]

Everyone seems to end up adding an external cooler. What makes you think you are different?

[neil68]

Neil - I think my motor is a similar spec to yours. You run 34 advance? I may ty and see what effect a little more advance has.

I ran with the top of the lid open but here the changeable weather can make that difficult.

Out of curiosity - you run the later wide fan shroud? What's the fit like with 48's? I have a genuine late doghouse one but thought there would be clearance issues with my 48's. Could you post a pic up of your motor on here for me?

I am beginning to wonder if my non-genuine shroud may be the problem

The reason for 34 degrees was my Dynojet testing and this brought maximum power with my previous Raptor cam (similar to FK47).

When I had Skat Trak manifolds & side entry banjo fittings, I needed to slightly dimple the doghouse shroud. I now run Jaycee top entry fuel fitting so that wouldn't require any mods to your OEM doghouse shroud.

I have never run an external cooler, stock doghouse only.

[Richierich56]

Ok - cheers Neil, I appreciate the advice.

[Martin S.]

Advance the timing until you hear it ping, and then back it off a bit.

[Richierich56]

Just as a follow up to this fellas - I put some new good quality foam on the oil cooler and fitted a full hoover bit (the one fitted had a section missing). Running 10w 30 oil and have stood the decklid off top and bottom. Made a huge difference to temps all round and now is running around 220f which is all good for me. Thanks for the help!