ABC'S of 80's Cooling Part IV - Hood Vents

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Huh? First I've heard of this. Any more details?

Basicly it is a ~5/16 coolant line to heat the throttle body to avoid freezing:rolleyes:

Side question I never figured out - Cooling is a big part of a SC but have you come up with any ideas on how to control EGT?
 
Basicly it is a ~5/16 coolant line to heat the throttle body to avoid freezing:rolleyes:

Yeah dont need THAT in SoCal. Might be a smog thing tho :hhmm:

Side question I never figured out - Cooling is a big part of a SC but have you come up with any ideas on how to control EGT?

Haven't even begun to tackle it. I guess I should start doing some mud searching :o
 
Good god. I just read through this thread and what a s*** show. And I am disappointed Sumotoy isn't around any longer the guy had some good ideas.

On that note I just ordered some Z34 vents. lol.
 
Just put a ram air scope on it. Ya really need some BIG holes to move serious amounts of air.
 
And, considering you vast knowledge of air flow/ pressure/ etc., just how many cfm do you expect those hood scoops to flow? At high rpm and considering many of us are running a souped up fan clutch that must be generating 5000-6000 cfm, I would guesstimate that we have 2-3 psi positive pressure under the hood. So how big of a hole in the hood will reduce pressure under the hood by at least 1 psi? I have been playing the "cooling game" for 5 years here in Phoenix and I have been tempted to do hood louvers, but my lack of knowledge in this area has kept me from moving forward on this. Seriously, john
 
Inkpot, I don't think there is enough information out there to do those calculations I would be really surprised though if there was 2psi of positive pressure under the hood. I mean it could happen but given the route for air under the truck I would just be surprised. I do think that there is a lot of air that is getting trapped under the hood though and I can feel it in both my 80's when I have driven them for a while. The fenders are hot, the hood is hot, and under hood components are too hot for my liking. I am not going to get caught up in the "does it make the engine run cooler" because for me it is a straw man argument. The engine is going to run close to thermostat temps as long as it can but but overwhelmed like in an oven, it won't be able to keep up. Letting hot air out and cooling under the hood is never going to be a bad idea.
 
I have been running an electric fan in place of the VC unit with excellent results (see thread in my sig) but, without doubt heat does get trapped under the bonnet at low speeds. As evidence of this my bonnet actually catches the panel at the bottom of the windscreen when I have been idling or driving in slowly while in hot weather, (yeh I hear you, lazy sod get out there and adjust it!)...soon, it has simply 'grown'. Presently that hot weather is sitting around 37 - 40c (96.8 - 104.0 F), but if I drive at speed and simply pull up and open the bonnet it does not catch, I can assume from this that at speed (perhaps over 40 MPH?) if there is any trapped air it is not hot enough to cause the bonnet to expand.

Re the vents, may fit them simply because they look good.

I read through Scott's (SUMOTOY) posts/threads and he has some very good observations and ideas, I contacted him privately a few months back for advice on the AC trinary switch to control the second speed of my electric engine cooling fan. Fortunately he is still about but not so active on MUD, hardly surprising given the crap thrown about, he came back with an idea and it was not just close to solving an issue I had.......it was spot on, forums can learn a lot from people like him IMO.

regards

Dave
 
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He isn't around because I am pretty sure he was banned for ruffling the feathers around here. lol

I have been running an electric fan in place of the VC unit with excellent results (see thread in my sig) but, without doubt heat does get trapped under the bonnet at low speeds. As evidence of this my bonnet actually catches the panel at the bottom of the windscreen when I have been idling or driving in slowly while in hot weather, it has simply 'grown'. Presently that hot weather is sitting around 37 - 40c (96.8 - 104.0 F), but if I drive at speed and simply pull up and open the bonnet it does not catch, I can assume from this that at speed (perhaps over 40 MPH?) if there is any trapped air it is not hot enough to cause the bonnet to expand.

May fit them simply because they look good.

I read through Scott's (SUMOTOY) posts/threads and he has some very good observations and ideas, I contacted him privately a few months back for advice on the AC trinary switch to control the second speed of my electric engine cooling fan. Fortunately he is still about but not so active on MUD, hardly surprising given the crap thrown about, he came back with an idea and it was not just close to solving an issue I had.......it was spot on, forums can learn a lot from people like him IMO.

regards

Dave
 
I agree. It does seem like the 80 series really heat sinks a lot more than other rigs. Forced induction seems to magnify the issue. We have done a lot of testing with different radiators, clutches, various cst ratings on silicones, different fans and positions, even different "freons" to reduce the heat generated by the A/C system. While there have been SOME encouraging results, there have been no miracle cures. Maybe someone will come up with a magic combination that let's me always stay under 200 degrees on water temp while it is 115 in Phoenix, and I am either storming up the mountain WOT or rock crawling thru the desert. I guess we just hafta keep looking......
 
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These are off a Pontiac GTP, its a very popular option and cost is low.
 
He isn't around because I am pretty sure he was banned for ruffling the feathers around here. lol

HYJACK ON

I did not research into why he left or if he was banned as that is not my business but, suffice to say he does not appear to be about on this particular forum. I do recall he made certain claims that were IMO absolutely correct and some IMO not so correct but, I would never allow it to become a slanging match which may or may not be the case here and therein is the issue 'IMO' or in MY opinion.

Forums attract all types of people with differing needs and skills, everyone from a 'newbie' owner who knows nothing about his particular vehicle (or perhaps any other vehicle for that matter), and needs to know if he has the skills to change the spark plugs, and at the other end of the spectrum someone like myself who has spent most of his life under the bonnet of a car (and commercial vehicles) and has amassed a hell of a lot of knowledge and experience about different marques, which I am able to draw on and am willing to share. I join forums like this to increase my knowledge of the particular vehicle I own, or forums that show my particular vehicle being used in the environment that I intend to use it. I may be simply throwing an idea out there for other members opinions, I then have to take the replies and draw my own conclusions. You then get the opinions and experience of hundreds of same model owners, I also offer my thoughts on other members vehicles which may or may not be of assistance, a 'win win' scenario for everyone.............and I would add all for free!

However, in that 'range' of members you get the 'I do not think that such and such repair/modification will work' members, these people may not have actually tried what you are suggesting, just giving the benefit of their opinion which is great. Then there are unfortunately those that 'know for a fact' it will not work despite not having actually tried the proposed repair/modification or witnessed anything similar, then along comes a supporter from the 'I do not have a clue' camp and they know even less but need a 'crutch' to support and front their weak personality, in essence online 'ganging up'. Eventually you end up alienating contributors, whether they are right or wrong is not the issue, it is how they and their 'challengers' debate the idea/modification/issue. But this now brings in personality clashes, and some in their frustration who lack diplomacy may end up getting banned, or someone like myself who has experienced a similar situation (coincidently on this forum) simply wrote a nice neat post, clearly pointing out my opinion/position and left the arena leaving the 'know for a facts' and 'don't have a clues' leafing through a thesaurus trying to work out what the words in my post actually meant. This gives time for the more 'mouth first brain engaged later' members attitude to work out what you are saying, the result is a more structured debate with everyone offering their opinions in a respectful and diplomatic way.

As mentioned in an earlier post I asked for SUMOTOY (found him via an AUDI forum) to give me some help with the control of my electric engine cooling fan, he had mentioned the use of the trinary switch. My spanner training in 1970's (yes I really am that old :flipoff2:) in the UK climate meant we rarely saw vehicles with AC, so I was unable to draw on my own experience.

Whether SUMOTOY jumped or was pushed is not my business but, a fair bet is he would probably still be here if a little more respect/diplomacy had been exercised by all, in particular those members with plumage who still have their heads buried in the sand.

HYJACK OFF....sorry....:redface:

regards

Dave
 
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Yep I don't disagree with you Dave.

Even if you read this thread he was definitely pushed by some because they didn't care for his mod and one even had monetary gain on the line by pushing.

I think the climate here has changed in the last 5 years where people are more open minded.

If you talk to him again tell him to come back. Lol
 
When I was running my business, (30 years) everything I built was a prototypy. Perfection Is a lofty goal and my work was an attempt to reach this. I am wise enough to know there are no perfect deals. I can tell when a man's heart Is In his efforts, and I take from that what helps me learn. I am amazed at the level of skill of the members here. I agree with you Scotty, I hope he comes back.
 
Or cut some holes in your hood and be an innovator and you can tell everyone else how it helped you? ;) lol

If I were to do that, I would certainly do some hard before/after numbers with holes open/ closed to give some good comparison values. Only thing I have found so far was from non-80s, and the results were a little disappointing unless the holes are obnoxiously large.
 

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