I've got a problem. I have a 97 EFI F250 4x4 w/auto trans. I do some pulling, mainly just a driver.

I've talked to Summit/Hedman directly and the kit for the AIR headers is not avail in ceramic for a few weeks and is a mid-length header w/the y-pipe.

L&L has the one I need in stock, about the same money as the Hedman ones, but I have to fab a new y-pipe. Being in Maricopa County Arizona, that means I have to put the cat converter back in that the last owner chopped out. L&L's are only plated for rust proofing, not ceramic to keep the heat down.

Hedman recommended Thorley headers, which are ceramic, in stock and come with a weld-up y-pipe. They are also several hundred $$ more and require the new cat.

Questions:
1. Anyone tried the L&L and notice a temp difference compared to ceramic coated? I also noted an article that said the did not hold up well at all appearance wise, not that it is a real concern of mine.

2. I've always been of the thought that unless you go with long tubes, you aren't really getting much. Thorley notes main power gains in the mid-range. Anyone try these?

3. Jegs lists a Magnaflow hi-flow 3" cat, appears to be universal fit, for about $100. Any idea how these work over the $300 Magnaflow ones Summit has that are direct replacement for the OEM one, which was already cut out when the previous owner put a new cat-back Flowmaster system in.

There was an article out there that was done on a fuel mileage build that tested how individual parts, inc hi-flow cats, effected mileage. They used a Random Technologies one, which runs $243. Worth it? It also mentioned using a 61mm twin-blade throttle body. Anyone run that?

Thanks for any help. I'd like to have them early next week, so in stock is important. Need to tow the car and trailer the weekend after.

 

I ordered a set of ceramic Hedmans (89516 is the part #) a month ago after Summit and Hedman both told me the wait time would be about 4 weeks. 3 days later they were sitting on my porch. I don't think Hedmans inventory system is very accurate...

Is your truck broken, or are you just looking to upgrade? If it runs, then I'd wait and get whatever you really want.

 

I just ordered the L&L in black paint. I live here in Phoenix and Jet-hot is located in the metro. They prefer them in paint, not nickel, so it saved me a little money any way.

I talked to the guys at Summit, Jegs, Heddman and L&L. I did some research as well. It appears the tri-y are great if running RPM range 3500-5500. Other than that, 4 into 1 are better.

Also, all the headers other than long-tubes are the same length as the stock manifolds, so "they just have that same short area before they put the gases tumbling back together", per the guy at Summit. They are better than stock, but not a lot.

I have to have a y-pipe made, but that is not significant. The coating sucks, as it's a 40% charge to rush, but I can get the better coating.

I also just went with a Magna-flow direct replacement cat, as they had it in stock. More money, but there are no universal fit that will handle the 460 in an F250.

Thanks for the info.

 

i have a 95 E350 with the thorley headers (unfortunately not ceramic and would prefer stainless anyway) and my muffler guy prefers to make his own Y-pipe. i have the single in/out cat which we chopped off enough of the inlet and outlet sides of the cat to be able to weld 3.5" exh tubing to the cat inlet and 3" to the outlet. that gave me a 3" min system from y_pipe thru the cat to which we added a 3" system w/ big block Flowmaster all the way back. according to jim (muffler guy), the stock cat has plenty of capacity for the big block once you open up the I/O.

hope this helps
neil

"It also mentioned using a 61mm twin-blade throttle body. Anyone run that?"

also, if you search my posts in the later model van forums (there are not that many) you will find some posts on throttle bodies that you can read as well as comments about the BBk unit i purchased. there are other performance comments in there as well.

 

Thanks. I am curious on the throttle body stuff. I'll do some looking.

 

lmk if you can't find anything. i will dig around and post some links.

neil

 

Shawn,
I have a set of nickel coated L&L's on my '78 F-250 4x4 with a 460. They are the fenderwell type, due to the d-60 front axle. I put them on in '97 and haven't touched them since, not even to retighten the header bolts. The appearance has deterioated, but it ain't no show truck.
Put a set of Hedman ceramic on a '66 (2 wheel drive) with a 460 a little over a year ago. Real pleased with them and far as fit and finish. They appear to be holding up well. The underhood running temp is lower than my '78.
Also have a '66 with a 390. Have an older set of Dyno Max headers on it. I had them ceramic coated about 10 years ago. The difference in the before and after underhood temp is amazing. Has to be at least 20-30 degrees difference, though I never measured. The coated headers also cool down much quicker than the uncoated ones. I just noticed some deterioration of the finish this year. Considering the headers were several years old when they were plated I have no complaints.
Hope this is helpful.

Roger Carter