Deeper thoughts about air flow

[Tacoclaw]

My truck's water still stays the same temp as before the twins. It is mostly due to the fact that I just don't work the truck that hard. It also has a lot to do with heat wrapping all underhood exhaust components, but I still think a twin truck would start overheating before a similar-powered single truck would.

I've also got an air-to-water IC setup, with the washer fluid tank as the reservoir. The water returns to the tank ice cold after going through an old AC condenser in the grill, so that stuff isn't too exotic to consider.

And in terms of stock parts being good enough for ??? Horsepower, they are. For dyno sessions. With whatever injectables are present.

There's probably nothing wrong with the stock inlet, but of you're able to make one yourself then go for it. Or find an upgrade for cheap somewhere. Just because they're good enough doesn't mean you need to settle for them. How much $$/time you spend on making one is up to you, but if you've got the means I see no reason to stick with a stock inlet.

[cmann250]

Tacoclaw- Don't take me wrong, i'm not against twins and if the super40 doesn't spool like i want it to, i'm going to look seriously into twins. But the coolant temp getting warmer especially when towing is what concerns me. Do you still run the stock fan or electric fans? I have a feeling that electric fans and a larger aluminum radiator would help, especially towing at a slow speed. My issue with the the air to water intercooler is the potential for coolant leaks. I'm sure your system is well engineered, but i can deal with a boost leak, not coolant leaks. My coolant temps never got to the 4th line (thermostat opens at the 2nd line in my '89 gauge cluster), and i confess that i don't have a pyro (i have a scientific reason, but i will get gauges soon). I don't even know if i'll need twins unless some one has a super40 and non-IC'd injectors and they already run too hot.

On the intake, i'm going to improve it some how because anything is better than what i have now. BC847 had some good explainations that made alot of sense to me

[ahale2772]

honestly, I dont believe that modifying an intake plate does that much good, I can see a larger inlet doing good things for you but #1 and #6 need more than just a bit of diverted air to keep them happy



this^^^ is the bump that #1 needs to fight against, pluss that runner is directed away from airflow, airt needs to go up, around and make its way into the runner wich not only affects volume and pressure, but changes how the air enters the valve bowl....lots of badness IMO

[Tacoclaw]

Well engineered.

I don't even have clamps on 75% of my fittings on that thing. All it is is 5/8 heater hose and barbs. I do get it though, no use adding more headaches. Just letting you know they're not as exotic as most think.

Stock fan, shroud, and thermostat. My coolant temps used to hang between the first fat mark and the first skinny one. Once I put that ac condenser in front of my radiator it hangs at the first skinny one all the time now.

I forgot to add that my twins have an oil leak. Right at the primary drain, so once again no use adding complication of you don't need it. Unless you're racing someone while you're towing, or towing at extremely high elevations, I would think a super 40 or S300 would cool any load a 1stgen can handle easily.

[oldestof11]

cmann, if the Super 40 is too slow for spooling, twins will not help.

[cmann250]

cmann, if the Super 40 is too slow for spooling, twins will not help.

Open mouth, insert foot. I spoke with out thinking.I believe the H1C i have now has an 18 or 18.5 cm exhaust housing vs the Super 40 having a 16 cm housing, so spooling shouldn't be an issue.

Ahale2772- That's the kind of info that means something to me, thanks. I can't do anything about that bump without gitting rid of the intake log, correct? So that is why there is a marginal gain with a twin intake. It makes sense! I hadn't seen inside a head before. My non-IC'd intake plate has the hole towards the front IIRC. I'd need an IC'd one that has the hole in the center or i could go fancy and make a twin intake plate, either way i would need a new one or i would have crazy angles in my IC tubes

[PToombs]

If you had engine overheat problems before it may have been from the old trans too. Is the heat exchanger still on the truck? Any excess heat generated by the loose converter is dumped into the coolant 1st, then to the air. Your new trans may cool the engine off quite a bit, just by being tighter. Something else to think about.

[cmann250]

That is a good thought Pete, i didn't reconnect it and i'm thinking of getting rid of it. I'll upgrade to a bigger trans cooler in the grille because the stock one is pretty pathetic

[ahale2772]

yeah, not much you can do about that bump with the head on the truck, If it was off you could definently die grind it down and stick a small bolt in it to plug it, you can just barely see threads in the center of that bump, it simply a casting mark for some mount hole

[Broncman]

Air flow...Adding a larger volume intake can also slow down air charge velocity so think about that as well.

Maybe I missed it but sounds like you have an auto tranny. That can add a good amount of heat in itself. Get a good seperate cooler with its own fan mounted under the bed etc. Is your radiator in "bloom"?? Look down inside at the tubes and see if they have grown mineral deposits from what is called solder bloom...



i just installed a S300 into a 93 that I am playing with. I have stock fuel pin turned backwards and just a little on the fuel screw. I have installed a Data Logging system to monitor PreIntercooler Air temps,Post Intercooler air temps, Both ends of stock exhaust manifold (cylinders 1,2,3 and 4,5,6) and Post turbo temps, as well as boost.

I just got my tag today for the truck and going to hook it to my loaded trailer hopefully this weekend and hit on of the biggest grades in North Carolina. Going to log the whole pull so I know EXACTLY what and where the temps come from and what needs upgrading if anything!

I have a 4 inch downpipe and allready notice a big difference in pre and post turbo temps. As much as 400 degress!
So far the intake air temps from the IC has not gotten very hot but I have not towed with it yet...

[cmann250]

Broncman- Thanks for collecting all that info. I already plan in buying a larger trans cooler because the stock one has the fluid doing one loop and then it's sending it back. My radiator is clean too.
I derailed myself on coolant temp when i was thinking about twins. I have never had coolant temp issues, even towing moderately heavy and my IP is just shy of run away, with stock turbo. Pete brought up a good point about my 47RH creating less heat than my 727, so i should run cooler than ever before. I don't have gauges yet, but i suspect my EGT's are sane, as smokinfirstgen has the same fuel and air settings as me, except he has PODS, and the highest he has seen on his pyro is 1400*. I'll be ordering a pyro, boost, and trans temp gauges soon.

[rockbuggy4x4]

wow great info everyone. I learned quite a bit just reading through this

[dunes450r]

i think the difference in coolant temps between compounds and a single would be fairly negligible if the HP and all other factors were the same. Virtually all the airflow is coming in from the front pushing the hot air around the turbo piping out the back. at slow speeds this might change a little, but the fan will start pulling lots of air through in the same fashion. I think the biggest difference in coolant temps between the two comes from the compounds supporting higher HP's and demanding more from the cooling system than it can provide.

not to discourage you from you twin intake either, but I doubt you'll see much if any difference from it. as others have said there are too many pickups with single intakes/stock intakes that are pushing more power than you'll be after without any issues.

[cmann250]

The info's still good, but none of this ever happened. I made this thread 18 months ago and since then I discovered that it took a lot less than I originally thought to get to where I wanted to be.

[rockbuggy4x4]

cmann, What did you end up doing to it then?