When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Has anyone had issues with these headers leaking at the connection to the exhaust? SLP didn't include any mounting hardware.
One header has one elongated bolt hole for a stud, the other header has two. IIRC, the two stud header is driver's side and the one stud header is passenger side. Anybody know for sure?
Did you have to drop your exhaust to get them on ? I did.
Also, did your set come with bolts? Mine didn't. I bought some Allen bolts from Napa because the stock bolts are 9/16ths and wouldn't clear the curve of the headers.
There is a seperate mounting kit that you can buy for ~ 40 bucks from SLP. It comes with 12point bolts, and gaskets for the SLP headers, although buying your own from NAPA should work just fine.. Just make sure you get them torqued down real good, or you will have exhaust leaks.
You might want to pull those bolts and put a little Lock Tite on each one.
:nono: :nono: .. never put Lock Tite on any exhaust bolts.. Being connected to the manifolds, those bolts will get EXTREMELY hot, and will expand, tightening them in the heads. If anything, use anti-sieze on all of my manifold bolts, to ensure they come out the next time you need to remove them. (This is much more important on 1) spark plugs, 2) manifold to cat bolts, 3) AIR tube to manifold connection, but you still may want to do it on the manifold to head bolts).
I bought the installation kit from SLP. I think you'll need to use 12 point bolts on the drivers side towards the back of the engine. It's pretty tight back there to get a hex socket or wrench to really torque the bolts down.
If anything, use antiseize, and if you want to be sure it stays tight, use locking header bolts ( the kind that come with a locking washer that is held by a c clip. )
Do the SLP's have individual flanges ?
I installed a set of Lingenfelter shorties on my 94 back in July.
They have individual flanges and it was a bitch getting the flange holes lined up with the holes in the head. They did a half-assed job welding these.I ended up making my own tool to spread the tubes/flanges but a friend of mine just found this: 13000 EXHAUST MANIFOLD SPREADER
I also had an exhaust leak on the pass.side at the collector.
Installing shorties was a complete waste of time IMO.
If you're going to do it my advice would be to tighten the collector bolts evenly if you want to avoid leaks. When you get them all tight crank em down good.
Use anit-sieze on all the bolts.
Good luck.
Why? I was looking to do this. What was the problem?
You arent going to see much, if any, improvement in power. I installed mine because my old set was damaged, and a set of SLP were cheaper then new stock manifolds.. Though the performance gain was marginal, they do give me much easier access to the spark plugs!! :)
The SLP shortie headers have pretty good fit and Finish. I had no alignment problems during installation. I used their installation kit and have had no exhaust leaks.
Shortie headers will not give much of a performance gain, I knew this when I installed mine, but they look alot better than rusty manifolds.
Long tube headers are the way to go for maximum performance but you will not be able to retain your factory cats.
Well, you won't like to hear this, but the SLP shorty's are flawed in design in my opinion - I really think the factory cast iron manifolds will outflow the SLP's, yes I do think the SLP's will cost you power. I bought five different sets of shorties, returned four of them for design flaws.
Here is what I observed on the SLP's that were sent to me: their collector design pinched the primary tubes down at the collector to almost 1/2 the size of the primary tube. As far as I know they still have the same flawed collector design. If I remember correctly, they also lacked the proper raised "D" port shape of the exhaust flange where it meets the cylinder head port. This is bad for flow too, since most exhaust flow happens at the roof of the port, which the SLP port mismatch slightly blocks. Send them back and use the money on something else.
I ended up with Watson LT1 shortys, which I have been told are no longer made. The LPE headers would be my choice if I were currently buying shorty's for an LT1. Interesting note: I always thought the Hooker shorty's were the same as the LPE headers - but the last two sets of Hooker LT1 headers that I saw both lacked the raised "D" port exhaust flange.
On a stock LT1 I think the shorty's are worth exactly 0 horsepower, on my modded engine maybe only 8 hp.
Psst, wanna get all the gain of shorty's without spending much money and getting no installation hassles? I found this one after I installed my shorty's: install a stainless steel sheetmetal divider between the center two cylinders on each side of the factory cast iron exhaust manifolds. On the stock LT1/4 cast iron manifolds they are cast with a common siamese port for the center two cylinders. After removing the factory manifolds just take a small cut off wheel and make a shallow notch top and bottom on the center siamese port. Then cut out a stainless steel divider to fit as far down the port as possible. Leave "tabs" that will fit into the slots. I understand that others who have done this on modded engines have gained as much as 10 hp, virtually equal to the best any shorty could do on a modded engine.
Now long tube headers are a different story, I think any engine will show a gain with long tubes unless there is a design flaw.
Like the guys said there really is no performance gain. They do look nice and plug access is better but the problems with the collector leaking and lining up holes it just wasen't worth the headache and this is despite the fact I only paid $200 for the headers (used) which were in excellent condition.
The reason I went with the shorties, as I'm sure most people do, was for emissions. If you don't have to deal with emissions go with long tubes and no cats.
Sounds like the SLP's may be a better fit from what everyone is saying here.
The LPE headers would be my choice if I were currently buying shorty's for an LT1. Interesting note: I always thought the Hooker shorty's were the same as the LPE headers - but the last two sets of Hooker LT1 headers that I saw both lacked the raised "D" port exhaust flange.
Yes, the Hookers and LPE shorties are NOT the same, I don't know why people think they are. The LPE's have individual flanges which are also thicker.
The nice thing about the Hooker's is they have a single flange like the stock manifolds do. It insures the bolt holes will line up, which is where I had some trouble with the LPE's.