we all know about the reverse cooling the LTx motors use, but what about a completely seperate cooling system for the heads?
one of the big helping hands that allows 12:1 compression on pump gas with those motors is the cooler heads from reverse cooling. so, why not apply this to other engines?
anyone seen a setup like this?
i was thinking maybe a smaller radiator mounted up front with an electric waterpump and some sort of thermostat setup. the heads can be machined to accept a/n fittings on each end, and have a crossover tube on the rear of the motor, just like an LT1.
head gaskets will need to be custom, with no holes for the coolant passages from the block.
im mainly trying to adapt this setup to an oldsmobile 455 with edelbrock aluminum heads.
what do you guys think?

 

....thats a really good idea (not expert just enthusiast)


i'm not sure of the specifics, but a lot of bowtie blocks are reverse cooled by hooking the hose up to the heads first right?

is a lower operating temp acceptable to the heads? high temp is important for the cylinders/pisonts i know, though even if the heads have similar requirements you could change the clearances to allow lower temps right?

 

Yes I have seen this. In fact I could give you the name of a guy in Maine who pulled this off quite well. I'd have to find his number though.

Bret

 

did it allow wildly high compression like 13ish on pump gas?

 

well it was used to help get high compression. Hell as long as you make a good chamber, cool that SOB well and don't run to much timing at the low end 12:1 is doable on a SBC, the LS1 burns so well that 11.5:1 is easy.

13:1 even on a pump gas motor is not going to live very long, I don't care how you cool it. I know for sure that a 13.5:1 engine on 92-93-94 is east it self up on a dyno.

Bret

 

The first step in designing a better system is to always find the inefficiency in the current system and address it accordingly. I think alot of times people think well but miss the real point.
That said, the ideal situation is lateral coolant flow and uniform thermal conditions throughout all cylinders. That requires some forethought but it is a situation always addressed in Formula One and other race engine designs, via two external water pumps at each side of the cylinder block.
Unfortunately we have to deal with what we've been given and sadly enough, it falls a little short of F1 technology.

The dilemma with any siamese-port cylinder head design is one of addressing the heat between our paired exhaust valves. The LT1's "reverse cool" helps but it is only a band aid to a poor cylinder head design. The LS1 on the other hand was designed the way GM should have built em in the first place.... eliminate the paired exhaust valves. Solution, buy an old set of Dart SBC/Buick heads and do it right. J/K... wouldn't work on your Oldsmobile anyway.

The only problem I have with your method is that it doesn't really address the main issue. Plumbing coolant into the front and back of the cylinder head helps, especially where aftermarket aluminum castings are concerned, but it doesn't really address the siamesed-exhaust port situation we've been discussing. The most effective system will be one which moves coolant effectively to or from this area.

Food for thought.

Chuck Riddeck
Progressive Race Engine Development

 

So as Chuck says,

Put some Splayed Valve heads on that thing. The IMSA GTP INTREPIDS made by Katech had these, and I think Mark Steilow got a set for one of his cars.

Yeah Chevy on has a few of these head designs, the LS1, the SB2 and the Splayed Valve.

You could also coat the exhaust ports and that will do some of the same thing. I really feel that good coating along with reverse cool is the best way to keep the heat in the engine down.

Will it let you run more compression, marginally, but it will keep the heat in and make more power, it turns that heat into HP rather than letting it excaps thru the rest of the engine.

Bret

 

i tapped off my waterpump and ran a -8 line to the center of the exhaust ports to help with uniform cooling considering i'll be running a good amount of boost

 

this idea sounds pretty good. using a 2nd cooling system for the heads, pump the coolant into the head right there between the exhaust ports, and let it flow out each end. but, im wondering if there may be problems with cracking and such with the -8 rigging?
olds heads have the same pos siamesed exhaust port setup as a sbc. anyways, i would like to get 11.5:1 compression with an olds and run on pump gas!!
thanks for the replies, very informative.
jeremy

 

there shouldn't be any problems with cracking as long as the deck is thick enough

on my brodix heads there was already a small indention on the head between the ports so that you had something to start to drill

 

Like this, si?

I have some really interesting data i can get ahold of, that my partner got from a yearly GM Engineering conference, along with graphs, charts, and heat maps etc. of various cylinder heads if you guys are curious. That's if it doesnt have anything on it I'm not supposed to share.. I'd have to check to be 100%.. but If i can post em, I think some of ya would enjoy

-Phil

 

Yup, just like that

I have a stewart waterpump that is already tapped at the ends and on the sides

They wanted me to run a -10 line there but i thought that was excessive, so -8 i think is good