1988 Dewiit fan worthless
Former Vendor
Joined: Jan 2000
Posts: 5,593
Likes: 631
From: Brighton
Thank you.
It does that, actually 2360
I think the correct word would be "hoped", but it didn't.
Now that we know you are dealing with rare and unusual ambient air temperatures, one thing you might want to try is to pack the gaps around the radiator. Inside the plastic shroud you will find about an inch gap on each side and top and bottom. Since the puller fan is acting like a vacuum air will try to take the path of least resistance and you are loosing some air around the radiator. The fact that all the air is pulling through the ac condensor, and you noticed a difference there, packing the radiator should do the same thing.
You could also reduce coolant temperatures by relocating the AC condensor forward, creating a gap behind the condensor. Since the condensor is mounted tight to the box, all the heat remove from the cockpit is transfered to the radiator. If there was a gap, the fan would suck in some fresh air. Obviously the AC function will drop off and it might not cool inside as well but if you have the optional pusher fan it will be fine.
It does that, actually 2360
Now that we know you are dealing with rare and unusual ambient air temperatures, one thing you might want to try is to pack the gaps around the radiator. Inside the plastic shroud you will find about an inch gap on each side and top and bottom. Since the puller fan is acting like a vacuum air will try to take the path of least resistance and you are loosing some air around the radiator. The fact that all the air is pulling through the ac condensor, and you noticed a difference there, packing the radiator should do the same thing.
You could also reduce coolant temperatures by relocating the AC condensor forward, creating a gap behind the condensor. Since the condensor is mounted tight to the box, all the heat remove from the cockpit is transfered to the radiator. If there was a gap, the fan would suck in some fresh air. Obviously the AC function will drop off and it might not cool inside as well but if you have the optional pusher fan it will be fine.
Last edited by Tom@Dewitt; Jul 22, 2013 at 08:56 PM.
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
If I had posted a thread wrongly claiming that someone elses product is "worthless", I would be on my hands and knees apologizing to that person; not doing it indirectly and casually. Afterall, it was the op not following the included instructions that resulted in him having to redrill the fan and/or the mounts. I mentioned in 2 previous posts, that there can be other factors other than the fan and radiator that can cause a motor to run hot and to check the timing and other areas. I guess a person who doesn't want help can't be helped.
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
The OP should take notice that the vendor he trashed is trying to help him. How many times do you see owners of companies taking time out of their schedule to answer one customer's complaint? I'll bet he doesn't get that kind of response from American Eagle Radiator.
Thread Starter
Drifting
Joined: Dec 2011
Posts: 1,439
Likes: 23
From: mesa az
C4inMesa,
My 88 vert is a stock 47k car. I changed tstat to 180, added an old mid america fan switch (205 on, 190 off) for the aux fan and added a prom to turn my main fan on at 200 and off at 180 like others have. My freeway temps in town in 105 degree heat is about 195 consistently.
At idle in city traffic I hit can still hit 218. At idle, the heat pulled out of the radiator just soaks into the motor, regardless of how many CFMs you have. With yours hitting 230, I would make sure that your mixture is 50% water, 50% antifreeze + 2 Bottles of Wetter Water. If that doesn't bring it down, you must have your timing advanced as others have stated.
Heat is a killer! Good luck!
My 88 vert is a stock 47k car. I changed tstat to 180, added an old mid america fan switch (205 on, 190 off) for the aux fan and added a prom to turn my main fan on at 200 and off at 180 like others have. My freeway temps in town in 105 degree heat is about 195 consistently.
At idle in city traffic I hit can still hit 218. At idle, the heat pulled out of the radiator just soaks into the motor, regardless of how many CFMs you have. With yours hitting 230, I would make sure that your mixture is 50% water, 50% antifreeze + 2 Bottles of Wetter Water. If that doesn't bring it down, you must have your timing advanced as others have stated.
Heat is a killer! Good luck!
Thread Starter
Drifting
Joined: Dec 2011
Posts: 1,439
Likes: 23
From: mesa az
I never smashed trashed or made any negative remarks about Corvette Central. They are great and I continue to spend several hundreds of dollars on their stuff. I do however feel the Dewitt fan is not worth the $200. Oh and American Eagle radiator is not a retailer. I bought it off ebay from CA. Complete money back guarantee. But lets remember that the American Eagle radiator is awesome. Delivered to my door for $180.
Thread Starter
Drifting
Joined: Dec 2011
Posts: 1,439
Likes: 23
From: mesa az
Thank you.
It does that, actually 2360
I think the correct word would be "hoped", but it didn't.
Now that we know you are dealing with rare and unusual ambient air temperatures, one thing you might want to try is to pack the gaps around the radiator. Inside the plastic shroud you will find about an inch gap on each side and top and bottom. Since the puller fan is acting like a vacuum air will try to take the path of least resistance and you are loosing some air around the radiator. The fact that all the air is pulling through the ac condensor, and you noticed a difference there, packing the radiator should do the same thing.
You could also reduce coolant temperatures by relocating the AC condensor forward, creating a gap behind the condensor. Since the condensor is mounted tight to the box, all the heat remove from the cockpit is transfered to the radiator. If there was a gap, the fan would suck in some fresh air. Obviously the AC function will drop off and it might not cool inside as well but if you have the optional pusher fan it will be fine.
It does that, actually 2360
I think the correct word would be "hoped", but it didn't.
Now that we know you are dealing with rare and unusual ambient air temperatures, one thing you might want to try is to pack the gaps around the radiator. Inside the plastic shroud you will find about an inch gap on each side and top and bottom. Since the puller fan is acting like a vacuum air will try to take the path of least resistance and you are loosing some air around the radiator. The fact that all the air is pulling through the ac condensor, and you noticed a difference there, packing the radiator should do the same thing.
You could also reduce coolant temperatures by relocating the AC condensor forward, creating a gap behind the condensor. Since the condensor is mounted tight to the box, all the heat remove from the cockpit is transfered to the radiator. If there was a gap, the fan would suck in some fresh air. Obviously the AC function will drop off and it might not cool inside as well but if you have the optional pusher fan it will be fine.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Using the same exact fan you are
Stroker with Im guessing mid 5xx at the crank. Creates a lot of heat
Old GM 3 row (bought a DeWitts havent put it in yet
If your shroud isnt all that great you can make one dont space it too far out.
Flaps ( adding 2 more) can be bought from the Fan Man (google him) so at speed the air wont stall in there at speed.
This made a big difference in low speed/idle temps. Sealing it like Tom said helps too.
Just a thought
Are you using the right # radiator cap also?
Stroker with Im guessing mid 5xx at the crank. Creates a lot of heat
Old GM 3 row (bought a DeWitts havent put it in yet
If your shroud isnt all that great you can make one dont space it too far out.
Flaps ( adding 2 more) can be bought from the Fan Man (google him) so at speed the air wont stall in there at speed.
This made a big difference in low speed/idle temps. Sealing it like Tom said helps too.
Just a thought
Are you using the right # radiator cap also?
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Melting Slicks
Joined: Aug 2008
Posts: 2,082
Likes: 50
From: Palmdale CA
one more thought.. your gauge could be in error. I don't know if the 88 FSM gives a table for (temperature/resistance) values for the ECT probe, but if it does you could measure the resistance at 212°f (Boiling water) and compare this against the factory specs.
8th Gear
Joined: Jun 2013
Posts: 8
Likes: 0
My car has an aftermarket radiator and fan. Still heating up when idling, AC on. One day I got under the front and looked at the AC condenser. Could not believe how stopped up and dirty it was. Only. 6 years old too. I dont see how any air got through it. Maybe worth looking at yours.
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
You could also reduce coolant temperatures by relocating the AC condensor forward, creating a gap behind the condensor. Since the condensor is mounted tight to the box, all the heat remove from the cockpit is transfered to the radiator. If there was a gap, the fan would suck in some fresh air. Obviously the AC function will drop off and it might not cool inside as well but if you have the optional pusher fan it will be fine.
I especially liked Super98’s post on the prior page. Knowing 2400cfm gets about the equivalent of 9mph is something I can equate. That’s probably not enough air speed as I see temps climb when I’m below 15-20mph (with the A/C). BTW, I’m still running the stock fan. I also looked at the ECM programming and see it shuts off the fan at 11mph (1989 model year). That SOUNDS like they picked 5mph over the fan speed. With a DeWitts…or higher CFM fan, maybe that parameter should be raised?
The link to SPAL fan’s was also interesting considering it’s “best” 16” fan shows 2400 cfm on it’s spec’s page BUT 1910 cfm on the product page. I assume the difference includes loading in a radiator (i.e., real conditions)? It’s a great price too. This thread makes it appear less than adequate for the conditions posted by C4Mesa – that I also sometimes see.
In looking at the shroud (after Ron’s shroud picture), I’d forgotten the bottom half of the shroud is non-existent. There’s not really any gap on the side of the shroud but it’s only the top half. (Picture a complete shroud split horizontally with the bottom half omitted.) If the shroud make that much difference, a full shroud might be worth consideration.
In looking at all fans in general, anything is an option – if purchased with a shroud. I had been looking at DeWitt’s SPAL adapter before this thread made me reconsider output specs. Derale and FFDynamics sell SPAL type fans that SHOWED higher cfm values. But, it looks like I really need to consider the validity of their flow specs, adaptability to the stock shroud (versus buying a shroud), or even jumping to dual fans. Sound seemed worth considering too…but I have exhaust [level] pumped up to a pretty healthy level these days.
There's also consideration for electric load. Personally, I have outboard amplifiers for my stereo system. I haven't measured what they pull, but it's likely a real consideration. If I considered (or anyone considers) a fan that pulls 40-amps (or more), then you gotta start looking at the alternator. Maybe...
When it comes down to it, an electric water pump is a bigger consideration for modified motors than I originally thought. (I wonder how much compression C4Mesa is running?) It also seems likely you (C4Mesa) would have been disappointed in my fan suggestions (made prior to your purchase). They would have required a bit more adaptation, might not have mattered on sound level, and may not provide the level of cooling you need. You might have saved money though...
One other thought….people won’t even see this thread if searching titles for DeWitt’s fan performance. His name was misspelled! So….Eeeets aaallll gooood….
Last edited by GREGGPENN; Jul 23, 2013 at 04:48 PM.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 413
From: WV
Burning Brakes
Joined: Apr 2009
Posts: 1,185
Likes: 33
From: Charlotte Michigan
I was at the Dewitt factory yesterday and was very impressed with the products and talking to John there. I am very confident of the products as I bought just a single row unit for my '93 LT1. I also asked them about this particular thread and felt that they went above and beyond to meet the customers concerns. I would rather have a high quality product made in the USA than a Chinese unit. If you were to cut a cheaper unit in half and one from Dewitts you would see the difference in quality that was pointed out to me as fin contact to the tubes. I also feel that the quality of there fans they offer further enhance the Great radiators they make.
Thread Starter
Drifting
Joined: Dec 2011
Posts: 1,439
Likes: 23
From: mesa az
I was just out driving. A/C on full blast. Ambient temp 105. Freeway cruising speed 75mph. Oil temp 245-250. Coolant temp 215 driving. Stopped and it rose to 240-250. Drive again back to 215-220. The road surface temps are at least 150. Anyway curiosity got me and off the freeway back in city traffic soaring temps. I turned the A/C off and the coolant temps immediately fell to 205 within 2 miles. Keep in mind my Dewitt fan keeps my A/C ice cold. I'm sure the Dewitt radiator 2row 1" which is $350+ shipping. Is excellent quality. However I could not afford it. The chinese radiator is working wonderfully. Whether or not it breaks remains to be seen. I don't make big bucks and had to make my decision based on what I can afford.
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
back on post 58 I ask about the ac charge and type. Did you convert to 134a and is it possible it is overcharged? Believe me, it generates more heat and is compounded on a hot day if its overcharged. BTW most conversions require 80 percent of the orig. charge when running 134a.
Thread Starter
Drifting
Joined: Dec 2011
Posts: 1,439
Likes: 23
From: mesa az
The condenser relocation idea is a good one but we don’t have enough room without some major fabrication. When I installed my AE unit, I set it as far back as possible – with the condenser as far forward as possible. Because of the extra thickness and the limitation of the radiator “cabinet”, you can’t get much more than an inch separation. Mine’s been installed for 3 years now. I also see climbing idle temps when I’m running the A/C. Otherwise I’m good (with a hi-flow water pump and 383).
I especially liked Super98’s post on the prior page. Knowing 2400cfm gets about the equivalent of 9mph is something I can equate. That’s probably not enough air speed as I see temps climb when I’m below 15-20mph (with the A/C). BTW, I’m still running the stock fan. I also looked at the ECM programming and see it shuts off the fan at 11mph (1989 model year). That SOUNDS like they picked 5mph over the fan speed. With a DeWitts…or higher CFM fan, maybe that parameter should be raised?
The link to SPAL fan’s was also interesting considering it’s “best” 16” fan shows 2400 cfm on it’s spec’s page BUT 1910 cfm on the product page. I assume the difference includes loading in a radiator (i.e., real conditions)? It’s a great price too. This thread makes it appear less than adequate for the conditions posted by C4Mesa – that I also sometimes see.
In looking at the shroud (after Ron’s shroud picture), I’d forgotten the bottom half of the shroud is non-existent. There’s not really any gap on the side of the shroud but it’s only the top half. (Picture a complete shroud split horizontally with the bottom half omitted.) If the shroud make that much difference, a full shroud might be worth consideration.
In looking at all fans in general, anything is an option – if purchased with a shroud. I had been looking at DeWitt’s SPAL adapter before this thread made me reconsider output specs. Derale and FFDynamics sell SPAL type fans that SHOWED higher cfm values. But, it looks like I really need to consider the validity of their flow specs, adaptability to the stock shroud (versus buying a shroud), or even jumping to dual fans. Sound seemed worth considering too…but I have exhaust [level] pumped up to a pretty healthy level these days.
There's also consideration for electric load. Personally, I have outboard amplifiers for my stereo system. I haven't measured what they pull, but it's likely a real consideration. If I considered (or anyone considers) a fan that pulls 40-amps (or more), then you gotta start looking at the alternator. Maybe...
When it comes down to it, an electric water pump is a bigger consideration for modified motors than I originally thought. (I wonder how much compression C4Mesa is running?) It also seems likely you (C4Mesa) would have been disappointed in my fan suggestions (made prior to your purchase). They would have required a bit more adaptation, might not have mattered on sound level, and may not provide the level of cooling you need. You might have saved money though...
One other thought….people won’t even see this thread if searching titles for DeWitt’s fan performance. His name was misspelled! So….Eeeets aaallll gooood….
I especially liked Super98’s post on the prior page. Knowing 2400cfm gets about the equivalent of 9mph is something I can equate. That’s probably not enough air speed as I see temps climb when I’m below 15-20mph (with the A/C). BTW, I’m still running the stock fan. I also looked at the ECM programming and see it shuts off the fan at 11mph (1989 model year). That SOUNDS like they picked 5mph over the fan speed. With a DeWitts…or higher CFM fan, maybe that parameter should be raised?
The link to SPAL fan’s was also interesting considering it’s “best” 16” fan shows 2400 cfm on it’s spec’s page BUT 1910 cfm on the product page. I assume the difference includes loading in a radiator (i.e., real conditions)? It’s a great price too. This thread makes it appear less than adequate for the conditions posted by C4Mesa – that I also sometimes see.
In looking at the shroud (after Ron’s shroud picture), I’d forgotten the bottom half of the shroud is non-existent. There’s not really any gap on the side of the shroud but it’s only the top half. (Picture a complete shroud split horizontally with the bottom half omitted.) If the shroud make that much difference, a full shroud might be worth consideration.
In looking at all fans in general, anything is an option – if purchased with a shroud. I had been looking at DeWitt’s SPAL adapter before this thread made me reconsider output specs. Derale and FFDynamics sell SPAL type fans that SHOWED higher cfm values. But, it looks like I really need to consider the validity of their flow specs, adaptability to the stock shroud (versus buying a shroud), or even jumping to dual fans. Sound seemed worth considering too…but I have exhaust [level] pumped up to a pretty healthy level these days.
There's also consideration for electric load. Personally, I have outboard amplifiers for my stereo system. I haven't measured what they pull, but it's likely a real consideration. If I considered (or anyone considers) a fan that pulls 40-amps (or more), then you gotta start looking at the alternator. Maybe...
When it comes down to it, an electric water pump is a bigger consideration for modified motors than I originally thought. (I wonder how much compression C4Mesa is running?) It also seems likely you (C4Mesa) would have been disappointed in my fan suggestions (made prior to your purchase). They would have required a bit more adaptation, might not have mattered on sound level, and may not provide the level of cooling you need. You might have saved money though...
One other thought….people won’t even see this thread if searching titles for DeWitt’s fan performance. His name was misspelled! So….Eeeets aaallll gooood….
Last edited by C4in mesa; Jul 25, 2013 at 07:35 AM.
Former Vendor
Joined: Jan 2000
Posts: 5,593
Likes: 631
From: Brighton
PART NO: 30102120
PRODUCT NAME
2360 CFM 16" Spal Straight Blade Puller Fan
VA18-AP70/LL-86A
Safety Car
Joined: Jan 2004
Posts: 3,783
Likes: 15
From: Northern California
The DeWitt Spal fan is 2360 cfm and is a great product. If it doesn't cool your engine to what you Hoped for, then you have to use a different setup!
If you can't afford it, then save up! In the mean time stop trying to pass Blame on products or Businesses!...Mr. Dewitt has been nothing but, Patient and Helpful to you!...
Your Condescending remarks are getting old!...
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 413
From: WV
Would you stop complaining already!...
The DeWitt Spal fan is 2360 cfm and is a great product. If it doesn't cool your engine to what you Hoped for, then you have to use a different setup!
If you can't afford it, then save up! In the mean time stop trying to pass Blame on products or Businesses!...Mr. Dewitt has been nothing but, Patient and Helpful to you!...
Your Condescending remarks are getting old!...
The DeWitt Spal fan is 2360 cfm and is a great product. If it doesn't cool your engine to what you Hoped for, then you have to use a different setup!
If you can't afford it, then save up! In the mean time stop trying to pass Blame on products or Businesses!...Mr. Dewitt has been nothing but, Patient and Helpful to you!...
Your Condescending remarks are getting old!...
... You've had an offer from Corvette Central to return the fan and get your money back...Take them up on there offer and stop bit@hing about a product that only "you" seem to have a problem with...I don't know what your waiting for.. Go buy a different fan and stop crying..
....It's getting old....WW
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
Would you stop complaining already!...
The DeWitt Spal fan is 2360 cfm and is a great product. If it doesn't cool your engine to what you Hoped for, then you have to use a different setup!
If you can't afford it, then save up! In the mean time stop trying to pass Blame on products or Businesses!...Mr. Dewitt has been nothing but, Patient and Helpful to you!...
Your Condescending remarks are getting old!...
The DeWitt Spal fan is 2360 cfm and is a great product. If it doesn't cool your engine to what you Hoped for, then you have to use a different setup!
If you can't afford it, then save up! In the mean time stop trying to pass Blame on products or Businesses!...Mr. Dewitt has been nothing but, Patient and Helpful to you!...
Your Condescending remarks are getting old!...
Enough already! What the OP fails to accept is that the real problem is likely the Chinese radiator he got off eBay and has fallen in love with. Surface area of the cooling fins has everything to do with cooling capacity. I doubt seriously the Chinese version has anywhere near the capacity of a quality Dewitt model. If you live in extreme conditions, you need to install components suitable for the conditions. Had be paid the price for a quality radiator, the aftermarket fan may not have been needed.
I'll stand by my real world experience. My 396 produces some serious heat. I also live and drive in a hot climate. So I purchased a quality Dewitt radiator. I use a 195 thermostat. On a 100* day with the A/C on my coolant stays below 200 on the highway and rises 10-15 degrees in the city. The only reason the temperature rises is because that's when the fan turns on and off. And that's with stock fans!