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RamJet350 Header question

S10wildsides (I think thats right) was making the Ramjet's closed loop before GM was. I can't imagine if he was able to do that, that the MEFI4 is going to be much different.

Or is it so new no one has spent the time?

Been awhile since I looked, what are the Ramjets anyways...are they essentially a Vortec-style poppet valve injection system, or more "conventional" injection like the LSx motors?
 
I didn't study the design of the EFI system all that much. It's port fuel injection, requires vortec heads. I know they are not the standard Vortec poppet design, but not sure what they really are. I also know the injectors run at 28lbs/hr.

The MEFI4 controller isn't much different than the v3 one, and getting in it is not a problem. The biggest issue is it's a proprietary setup, not easily navigational for even technical people. All numbers and codes nothing really telling your what your changing. People have done it, don't get me wrong ,it can be done, especially if your just going after 1 thing to change.
 
Actually, I was just poking around again, looks like Arizona Speed has perfected the tuning of the MEFI4 controller. YOu used to have to send the thing to them. They got a purchasable software package for it now, $650 and it gives you laptop tuning to it.
I don't plan to tune it, I believe it will be fine out of the box, as I don't plan to modify the engine.

These headers are giving me a run for my decision making process. I'm torn between sending a set of Hedman's (69830, or 69230) out to Jet-Hot, or getting the Stainless Hookers (2454-2HKR). The stainless Hookers are for 2WD, so I wonder if they'll even fit to begin with. I couldn't find a set for any 4WD 73-87 GM .
I like those because they are stainless, so they will last, they have 3" collectors and 1-3/4" primaries. The Hedmans with Jet-Hot would be alot cheaper, but are smaller and shorter than the RamJet manual wants. They don't list the primary length, but looking at pictures of them installed here and on their website, they *look* alot shorter than 32". The stainless ones are very pricey though.
 
I have had Hedman shorties (on my Camaro) and Thorley Tri-Y's. I really like the Thorley's. The coating is a must have in my opinion as well. The Hedmans were uncoated and the underhood temp difference between the coated Thorleys and the Hedmans is huge (qualitatively speaking).

Is the Ramjet a sequential or batch fire injection system? If it's batch fire look into Megasquirt for engine control (much cheaper than $650). The MSII ecm allows for full control of fuel and spark. There are a few people using MS with addon control boards for sequential systems too.
 
For $650, plus the cost of the motor, you could probably be well into an LS series motor!

I'm a big fan of stainless, but I hate the collector flanges shown. If the 5/16" head flange is thick enough, I'd probably tolerate the difference. But you've got Thorley that is making stainless headers too, no idea if cost is comparable. Just giving an idea for another source, maybe they are cheaper, who knows.

I really dislike coatings, there are probably people not having any problems and that's what we don't hear, but there are quite a few that have had the coatings start "failing" in short order. And since you can't install these things without scraping against metal, the deterioration has already begun before you even use them the first time.

I like the idea of stainless simply because it should be a one time install, with gasket changes periodically.
 
Well, I think the RamJet 350 engine as delivered will work fine. It shouldn't require tuning. So I don't think I'll need any software or boxes.

I didn't find any Stainless thorleys, they make 'em, but nothing for our trucks. Some shorties if those are to your liking.
The stainless ones are supposed to keep heat pretty good just by their nature. I dislike coatings as well, but you gotta do something. Either that or buy a set of the $80 summits every year. I don't like much of the manufactuers coatings, but the Jet-Hot seems like it could be decent.
Ryoken was struglling with this for a while, what'd he do. Hmm..I'll have to go look....
 
I'm pretty sure my friend used jet hot on some headers for his mustang, twice. Both times the coating came off.

I'd really like to hear from folks that have had 0 issues with their coated headers, that have actually had the engine run with them on. :)

Hedman makes some good headers in the $200 range (the Elites) but I don't know as they'd hold up long with salt. They are about as thick as you commonly see, so it's not like they are any worse, just not sure if the $200 stuff would last any longer than the $80 ones. Flange thickness means nothing if the collector rots out first.
 
This can't be that hard. What does the factory use on performance vehicles. I wonder what's on my '04 GTO, I never looked. What do Corvettes use? My '86 Chevy C10 with the 4.3L v6, it has header like manifolds that came from the factory, that is they are mandrel bent tubes, not cast iron, med length. They look rusty, they are rusty, but in all the years, they have not rusted thru and are still quiet. There's really no sign of them rusting out, the surface is just rusty but hasn't really changed in years. These things are exposed to massive salt spray too, they are on my DD, and I drive 3-4 hours one way every other week to another state. Sometimes the whole way it's snowing slightly and the road is nothing but a salt spray booth.

These are OEM:
IMG_5403.jpg
Those are OEM.
 
I have had my coated Thorleys on and off a few times. I've scratched them pretty good in a few places and there is still no corrosion at all. I'm pretty sure the scratches (from rubbing on the frame during install or removal) are not through the entire thickness of the coating. I will try to get a few pics later.

These were ceramic coated when i bought them, not Jet-Hot.

Summit

I have a few thousand miles on my 383 with these headers.
 
Hmm...do you drive much in snow and salt and or rain there in NM? Much mud get thrown up on them? Just trying to get an idea of your driving conditions.
 
I have a set of the Thorleys, and I love them. They are the best headers I have had and are very durable. I would suggest looking into those, or try a custom set possibly from Sanderson.

Also the Hookers that you posted are for a BBC.
 
You are right, it shouldn't be hard. :)

I wonder if the factory stuff simply uses better steel than aftermarket. They couldn't trade off cost when it comes to reliability, especially with things like exhaust.

Don't forget, most aftermarket headers rot out first where the 4 tubes meet, because stuff gets trapped in there (dirt, water, salt). The factory ones don't have that "trap".

We don't use salt up here, and my truck doesn't get used for daily driving duties. At best they get wet once in awhile.

DSC01684.JPG


Yes, that's after a couple of years, and I MAY have gotten them too hot (although I didn't break the engine in on them) but I don't put more than 5000 miles on the truck a year.
 
nchinca said:
Also the Hookers that you posted are for a BBC.
Click to expand...

Whopps. Good catch. :eek1:
Hmm..I guess the number should be 2452-2HKR for the stainless. But those are 1-5/8" primaries with a 2.5" collector. Hmmm.....

dyeager535 said:
Don't forget, most aftermarket headers rot out first where the 4 tubes meet, because stuff gets trapped in there (dirt, water, salt). The factory ones don't have that "trap".
Click to expand...

Yeah, I'm all too familiar with that. I had a set of cheapy blackjacks on my k5 before I tore it down, and that's where they were rusted. Probably had less than 15000mi and 2 winters before they rusted out.
 
73k5blazer said:
Hmm...do you drive much in snow and salt and or rain there in NM? Much mud get thrown up on them? Just trying to get an idea of your driving conditions.
Click to expand...


I just moved to NM. I have lived in Wyoming for the past four years, two of which I drove this blazer with the headers. Lots of ice, snow and salt. I buried the truck to the rails in snow this last hunting season and also coated them in mud. The mud comes off, but can discolor the pretty silver color slightly.

I have broken in two cams with these headers.
 
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