Has Anyone Tried The Radiators By Dewitt?
Ive Got A 95 (had It For 9 Months), Runs At 196 Freeway, Air Off, 203, Air On. In Hot Weather (95-100) Runs At 225, Air On. Fans Work As Required (on At 225, Air On). No Visible Debris In Intake Or Between Condensor And Radiator. Air Dam Not Damaged. Replaced Hoses, Water Pump And Thermostat With Factory Items. No Bent Hoses Or Evidence Of Vacuum. Just Want This Thing To Run Cooler.

Dewitt Claims There Alum Radiator Has Two Cores Vs Factory Single Core, Up To 25 Degree Drop Due To Efficiency.

 

If you try the search, that topic recently came up.

You also might want to try a lower Tstat, and a fan switch (that would be cheaper/easier solution).

 

As I was told when I first asked about high running temps .... when ever you tour the AC on the 2df fan kicks in regardless of the temp.

Contrary to everything that I've ever been taught, when my engine beginns to run hot, I turn on the AC and it stays below 210. Even in a traffic jam.

 

The Dewitt radiator has a two row core as opposed to the stock single row core. It is a quality piece and you can't do better. But you really don't need a $500.00 radiator. Sorry, Tom. Your temps are great. They are where your engine was designed to run. This ain't your Father's Oldsmobile. If you would like to see the temps a bit lower, reprogram the fans to come on earlier. Also, "No Visible Debris In Intake Or Between Condenser And Radiator." doesn't mean a lot. One usually must at least remove the top section of the radiator shroud for a good inspection.

RACE ON!!!

 

save your money unless you see a lot of track time. your temp is optimal and is just a few degrees higher then mine at same outside temp. if you want it a few degrees cooler i would set a day aside and yank the radiator, you will be amazed at how much crud you will see between the fins, also if there are any bent fins i would straighten them.

 

Ok, Ill Pull The Rad And See If I Can Clean It Up A Bit And Have The On Reprogrammed.

Thanks To All For The Tips

 

No problem, you dirty rooten trader. I want that payoff money back

I agree that most people don't need the dual row radiator if everything is working right but that's a big IF. GM didn't put a single row radiator in the car because that's what it needed, they did it because of cost. If you only knew what I know about this process........
The biggest problem I see with the stock radiators is that GM designed them with absolutely zero extra. That means if you add this or add that performance item, the radiator is most likely not big enough. Or as many have said, once a few bugs and leaves get caught up in front, game over. If the radiator degrades a little with some crud, same thing. It was simply a very marginal system. I mean look at the radiators they installed in C2 and C3's, they are monsters in size compared to the late models. The second arguement for a all aluminum radiator is the common failures with the plastic tanks and gaskets. Most of these radiators never fail a "core" before the plastic tank cracks or you blow out one of the gaskets. So if a 100% tig welded radiator outlast the stock version by twice as long, then I guess it doesn't cost anything more? Pretty good spin on that one huh!

 

You mean traitor, not trader. And if the check clears, I'm keeping the money.My radiator core is the 1984 original, but I've had plastic tanks replaced, twice. I AM pretty good about semi annual flushes.Nice save!

RACE ON!!!

 

Pretty good? That was great!

 

My L98 was runnung a bit hot (for my comfort level). I'd estimate 220-230. As I had a leaking heater core AND an intake leaking oil from the rear block/manifold area, I started a major/minor redo. The parts I used...

DeWitts Dual Core Rad
Edelbrock Victor Water Pump
BeCool 180 T-Stat
ALL NEW HOSES, heater, Rad, Bypass, etc.
DexCool 50/50 mix w/distilled water
NAPA Pressure Cap
Fel-Pro Intake gasket kit

BTW, the hose running from the pump to the fill tank was a no-show for my 91 L98 (supposedly discontinued). I had to get one from a local machine shop as it's got different size terminations. All other hoses were GM direct. I tried the Autozone/Advance Auto/PEP Boys route and either NO ONE had listings for some/all of the hoses OR they were (what they could get) on BACK ORDER.

Final Results: Some may say that this is not a good thing...

The car now runs (if you can believe the instrument panel using a more or less linear interpretation of "where" the needle is) at appx 145-160 on the highway w/and w/o AC on. At idle, stopped, appx the same. In traffic, w/AC on, stop and go, in near grid lock on Rte 81 in 90 degree weather in Harrisburg, Pa it sits around 180-190 MAX!

I know some may balk at the low temps as the engine really should be at 180 or more for best efficiency (so I'm told), but I'm happy w/the cooler temps and getting 19-21 driving from Scranton to Harrisburg, Pa and around the town (combined). The lower temps may also have a slight bit of help from my Stainless LT headers that were JetHot coated. Either way, that's my experience. I wouldn't suggest that anyone replace the rad w/o doing a comprehensive parts replacement like I did. Just like when choosing cam/heads/intake... it's always best to "component-match" for a more effiecient system, regardless of what that system is.

One more thing, as the posts above suggested, when I pulled off my upper rad shroud, appx 1/3 of the rad was "clogged" with what looked like dust/grass clippings/etc. I also had a (slight) gathering of "stuff" at the bottom between the rad and the condenser. I'm certain that if I had just cleaned the rad that it would have helped somewhat. It was simply my choice to go the way I did... costly too... appx $900-$1000 altogether.

Hope this helps.

JM

 

For those just tuning in on the topic of C4 cooling issues,
be aware that although TheGuardian has switched from
glycol to DexCool, he did it as part of a complete system
change.

There have been several sad tales here and elsewhere
about the consequences of mixing these two coolants,
even by those who attempted to flush the glycol before
refilling with Dex. Some have speculated that even
leftover coolant residue that has permeated the gaskets
& hoses can initiate troubles due to incompatibility.

The wise route is to refill with a fresh charge of the OEM
A/F for your year C4. Mix this 50:50 with distilled water
and if you use glycol, replace it on a two-year cycle to keep
ahead of the corrosion when the additive package can no
longer protect from the electrolytic reaction that occurs
between dissimilar metals (alum & iron).

 

I neglected to mention the incompatability of Dex and the old standby green stuff (which i do still use in my Dodge Neon). Neither is truly bad/good/better, just different and unfortunately incompatable.

The results of mixing the two are VERY BAD! Usual results are clogged cooling systems. If "mostly" cleaned/flushed, the worst you might see is a film that looks a little like baked-on Gulden's Hot Mustard (I've seen that w/several of my friend's cars). I have been running Dex for about 6 years now. When I originally did this, I spent a few hours completely and meticulously draining/flushing the cooling system.

So, unless you have the time, use whatever you have been using. But if you're ready for a change, just remember to do a complete flush job!

Sorry if that point was somewhat ambiguous.

JM

 

I see two problems, here. First, you may think you like the low temps for now, but how happy will you be when you find your crankcase all sludged up? Not to mention the increased engine wear. Proper operating temps should help that gas mileage, too. Second, your "BeCool 180 T-Stat" must not be compatible with the "DeWitts Dual Core Rad", because the stat isn't closing. With a 180° thermostat, your engine cannot remain below approx 180° after warm up. That is what a thermostat does.

RACE ON!!!

 

This Is Why I Check This Site Every Day. More Good Poop From The Group Than You Can Shake A Stick At.
Thanks All For The Great Experiences And Info.

One More Question: Anyone Know Of A Rad Shop In North Sandiego Area That Has Experiece With C4 Systems And Hopefully The Dewitt Radiator?

 

This is all DIY stuff. A Saturday's afternoon with a 6 pack. First, flush it very, very, thoroughly. Then remove the radiator and clean the outside and straighten any bent fins. While the rad is out, you can see what may have accumulated between the radiator and the condenser. If course, clean out this area. If you have any doubts on the shape of the radiator, you can take it to a shop to have it flow tested and professionally cleaned, if necessary. Refill the system with the previously used type of coolant, and you should be good to go. Your present temps are about what they should be. The above procedure may drop them slightly. For a greater drop, add some Water Wetter to the cooling system and if you want it cooler, still, have the fans reprogrammed to come on at a lower temp...200° to 205°, maybe.

RACE ON!!!

 

when I change my ROYAL PURPLE oil if there's sludge or when I get into valve cover replacement in another month or so.

As to the temps, I like them just where they are. The engine compartment is plenty hot and I don't anticipate any premature wear. As I said earlier... if you can believe the interpretation of "where" the needle is... I don't have specs on the linearity properties of the temp sending unit/guage... so I am only speculating...

Lastly, I never said that I was shooting for good gas mileage. In order to do that, I'd have to stay off the go pedal??? If I was concerned about gas mileage, I'd get a YUGO... :-}

JM

 

that's not what CFI was getting at, JM. He's pointing out that you've gone from one "extreme" (normal operating temps and your perception that they are too high) to the other extreme of temps that are obviously TOO COLD at the expense of $1000 of your own money. Not to mention the increased cost of unnecessarily poor fuel economy, engine wear and reduced power output (yes HP drops when the temps get too cool). So in other words, you're doing things bass-ackwards for no good reason. Now if the dash guages are miscalibrated, that's one thing. but you said yourself you like the temps where they are so...

Anyway, you have a potent cooling system, but you do want to shoot for 180* coolant temps for max efficiency in all areas. In your case you have a supurb cooling system, you would just want to verify actual operating temps and if they remain too low as you state, change the T-stat to a 180* and reprogram the fans to come on around 190* or so. That would be ideal. But it's your car so all we can do is give free advice.

 

Were you intending to finish that thought, to form a sentence?


If course you wouldn't "anticipate any premature wear". If you did, wouldn't have modified your cooling system as you have. Not anticipating because of not knowing doesn't make the problems nonexistent. I think if I wasted "appx $900-$1000 altogether", I would feel compelled to say, "As to the temps, I like them just where they are.", too.


You said that your car runs "at appx 145-160 on the highway w/and w/o AC on.". Despite the possibility of a mis-"interpretation of "where" the needle is", I would expect you would want to hook up a known good gauge for verification purposes. Those highway temps on which you are "only speculating", indicates that your thermostat isn't opening. Whether you agree with conventional wisdom or not, I would think you would want to satisfy yourself that everything is operating as you believe it should.

I never said that you said that you said you were "shooting for good gas mileage.", but it was YOU that brought up the subject. I only commented on the point you raised.

RACE ON!!!

 

Just a little tech info on thermostats. They should start opening around 20 degrees less than rated and be fully open at the rated temp.
Personally I'd prefer 180 all the time.
BTW What does your oil temp run at?

 

READ THE TITLE NEXT TIME, CFI!!! That's where I start, but apparently you don't. If you'd like a more complete thought from me sometime, we can talk at an event like Carlisle.

Another point... the engine DOES COME UP TO TEMP! It simply runs a bit cooler on the highway WHERE I SELDOM DRIVE IT!

AS to WHY I upgraded, all of the upgrades I have done, ie: SuperRam Intake, headers, Random Tech Cat, B7B Cat Back, a purpose built trans w/B&M Converter w/billet flex plate and (YES) the cooling system (D44 is next) I have done so in anticipation of an engine build that certainly WILL run alot warmer when I drop in a 400+ ci SBC. I'm simply wringing out ALL of the supporting subsystems prior to upgrading the heart of the machine. The last thing I want is a list of unknowns when I drop in the engine, like some of the horror stories I've read on this site like the LT1 rebuild that can't start his engine (has spark, fuel, etc) or the others who've put together their SuperRam only to have coolant in their cylinders... and on and on and on...........

The reason for the lower temps on the highway... as I've stated where I seldom spend my time... are most likely due to the coolant bypass keeping enough of the coolant flowing (along w/the T-Stat partially opening) as well as the increased cooling capabilities of new DeWitts radiator.

Given the choice between running hot or running cool, I'll take cool. When did you last see someone blow a rad/heater hose, head gasket, tranny or any other of an assorted list of hardware running a cooler than what's considered normal engine. I can tell you that I've passed enough people on PA Rte's 81, 84, 80, 380, turnpike etc in my daily driver that had boiled over or blown a hose or two due to OVERtemp in stop/go gridlocked (construction, accidents,etc) traffic.

Just like in politics or better yet religion, YOU go your way and I'LL go YAHWEH.

JM