Faster flow...all things being equal...will improve the systems cooling capability, but only up until the point where the dwell time in the rad is too short to allow proper heat transfer. The good news, is that our little factory pump will never come close to this point. We did some research on this a while back, so I will have to dig it up....but rest assured that our stock pump isn't going to reduce dwell time in the rad to the point that cooling system effectiveness would be diminished.

For what it's worth, the engines we setup and tune have not spewed coolant. One exception is the sleeved blocks...which everyone has collectively have agreed, are presenting some issues with daily drivers. If your goal is a daily driver, unsleeved is the way to go. This will also save you about $2000 in sleeve/installation costs.

Everyone will have an opinion on how to best setup the engine/tune/cooling system for best results. At the end of the day, ask for the opinion, of the person that will back up your build if issues arise. The guys with some skin the game, are less likely to take needless risks, or take chances with a buildup.

On our track cars, we run Evans NPG, no thermostat, Koyo 52mm, and the cars run cool and strong. No froth, nothing in the overflow, no issues with the cooling system.

 

Thanks for your response Sharif...so I guess the thought that there should be a restrictor plate if the thermostat is removed doesnt apply to this motor...I know the evans thing is really big in the diesel performance world and they swear by it..I may try it eventually..

Go-Fast...sorry if I sounded like an ***..honestly I dont know you, your background etc etc..

Ironically enough, I bought a new radiator cap today just for grins...so I'll report back in a week and see if it was the culprit..I did buy an over the counter 13psi "stant" cap...its ugly but I'll see if its gonna work..
Tom

 

i actually enjoy remaining anonymous,but have plenty of vq experience.if you research my previous posts i'm sure you'll learn all about me and maybe a bit about other builders.(or maybe not considering all the threads that have been "sanitized")

 

Ok so I put the brand new rad cap on before I left for practice tonight...just drove normally until some green Z28 wanted to show his ***...I promptly handed it to him on a platter...LMAO guy wouldnt even come up next to me afterwards...dont get me wrong..I am not a street racer..just a little 2-3 shift action was enough for him..

anyway got home and checked the overflow bottle and its back up from "low" level to "full hot"..I'll lokk at it again in the am after it completely cools...and as always I should be able to pour it right back into the radiator...nothing in the oil, nothing in the coolant, just a nice bright green extra 4" in the overflow..go figure..


btw, I pulled this off my "Z stats" list I got when I bought the car...

Built, Balanced, and Blueprinted Bottom End w/ CP Pistons 8.5:1 compression,
Crower Rods, Cometic Head Gaskets, ARP Studs


any comments about the above?

 

What ARP studs....L19 or regular off-the-shelf ARP head studs.
What are you using to tune the engine?

 

if the coolant does not return on cooldown it has been replaced in the system by something else,does not sound good.post up the blueprint for the build so we know what they did with the motor.

 

go-fast
Yeah..thats what I keep saying..."air" Its wierd that the cooling system will push out about 4" of coolant into the overflow and after cooldown will not suck it back into the radiator, but again I can get out the funnel and dump it right back into the radiator and back to square one...I dont have the "blueprint" cant help there...All I have is the shop receipts showing the work done..


Sharif...I know I know! Greddy emanage blue...
In a email from the previous owner it said L19 but the receipt from the shop does not clarify..thats all I know..


From the receipts I have over 25K in work done to this car...it may not have the best engine managment, may not have every spec when they built it but this car is unbelievably fast and idles, runs etc as smooth as a sewing machine..the only issue is this coolant thing and its more of an annoyance than anything..I pop the hood prectically every time I drive it anyway to check oil etc etc.


And once again I originally posted this thread because I am not convinced I have a blown headgasket or any issue for that matter..

I guess the fastest way to tell is a cylinder pressure test right? wouldn't that immediately tell me if the gasket was bad?
I believe if coolant was getting into the cylinder it would hydrolock right? where else can it be going? There are no indicators in the oil, the coolant etc...only this mysterious issue of the coolant overflow bottle rising ...

 

people throw the term "balanced and blueprinted" around and i still haven't seen one sheet on a vq posted on this site.if you don't have a blueprint then it's not blueprinted,if someone claims it was ask them for the sheet.as far as a pressure test go,it might give you info but sometimes they only leak under certain conditions,so it could be hard to verify.eg. high boost or cold motor w/high dynamic load.it does sound like early warning for a hg though,you might want to deal with it now before you start hurting hard parts.

 

go-fast... I hardly keep any coolant in my overflow tank on my APS TT. Good or bad idea??

 

you only need enough to keep the pickup tube submerged,if your tracking the car consider slosh and g's.

 

So you're saying pull the heads now and check the gaskets?

you know one thing that I just realized may be causing this..and damn I feel stupid...if when the engine heats up and it wants to suck coolant out of the overflow...then like you said in the above post the hose needs to stay below the coolant level ...crap this might just be exactly what is causing my issue..now that i think about it..the line does look kinda short to me...gotta check that...


lol I've owned nothing but powerstroke diesels for the last 9 years(three of them)..and they have a freaking HUGE overflow / de-gas bottle...

 

if you level is low it will suck air,always check the simple stuff before taking the head gasket plunge.you should still be prepared for the worst,considering you have playing with coolant for so long you figure one time would have been close enough not to give symptoms.

 

Turn your heater on full blast...is it luke warm, or super hot?

 

Always been hot..never a problem there..I did find that the "hose" going down into the overflow bottle is actually shorter than the "low level" on the bottle..putting a new piece in right now..let you all know what I find..

 

It sounds like you just top it off & call it a day until it over-flows again. My coolant has never been that easy. I was thinking of switching to Evans NPG soon.
I have a similar set-up with CP, Crower, ARP standard. Not saying it's the best but it's worked for me.
I purchased the Cometic Head gasket, then heard nothing but trouble so I returned it. I chose to use a stock head gasket. (This was before the HKS head gasket was an option)

 

Well I am happy to report that there are no combustion gases in the coolant, coolant system held 13psi for 20Minutes with no leaks, I also reinstalled a new thermostat after seeing only 150 degrees in the am taking my daughter to school. So the coolant system works perfectly. I feel like an idiot though because the root of my coolant issues was the actual hose from the radiator neck to the overflow bottle...even though the hose was new it had a "pinch" clamp on it and it would not seal properly. This is the reason the coolant would push out to the bottle but would not suck back into the radiator. It works perfectly now with a new hose and screw clamp.

So no issues and no worries. Car is running like a sewing machine.

Props to UP-REV for their "Cipher" software...really cool laptop software for troubleshooting etc.

Just enjoying the ride now...

 

SWEET! Congrats