APS guys
Thread Starter
Le Mans Master
Joined: Jul 2005
Posts: 7,121
Likes: 3
From: Shreveport/Bossier Louisiana
St. Jude Donor '08
APS guys
Hey guys,
I bought the kit used (In GREAT shape) and the instructions call for studs to hold the exhaust manifolds to the heads. I didnt get these with my kit but is it ok to use my bolts or does it NEED studs ?
I bought the kit used (In GREAT shape) and the instructions call for studs to hold the exhaust manifolds to the heads. I didnt get these with my kit but is it ok to use my bolts or does it NEED studs ?
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From: Forney Texas
Thread Starter
Le Mans Master
Joined: Jul 2005
Posts: 7,121
Likes: 3
From: Shreveport/Bossier Louisiana
St. Jude Donor '08
I would recommend some good high grade studs. You want full thread purchase into the cylinder heads with the added weight. Not a place you want to cut corners and it's not too inexpensive to even consider cutting that corner. Call Will and tell him to send them to you as they're part of the kit.
Thread Starter
Le Mans Master
Joined: Jul 2005
Posts: 7,121
Likes: 3
From: Shreveport/Bossier Louisiana
St. Jude Donor '08
Sent the manifolds to Dallas to get ceramic coated but should have them by weeks end. Im jumping around on the instructions making cuts here and there.
Got the meth kit mounted and wired.
More tinkering continues today LOL
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From: Fort Wayne IN
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If you do go with the studs, be prepared to become a contortionist when you put the manifold in. The passenger side manifold will go on with the front four studs in place, but the drivers side manifold will NOT go in place with any in. I was fighting this for a couple of hours last night before giving up. I believe what you're going to have to do is hold the manifold up and start a couple then fights to get the rest of the holes lined up. There simply isn't the clearance on the drivers side.
I have the APR stainless studs, and I will forewarn you, the little tiny allen keys they are sized for like to strip out pretty quick. If this happens, use a second 6pt nut and jamb it and an ARP nut together and tighten the studs down using the jambed nuts.
I have the APR stainless studs, and I will forewarn you, the little tiny allen keys they are sized for like to strip out pretty quick. If this happens, use a second 6pt nut and jamb it and an ARP nut together and tighten the studs down using the jambed nuts.
Thread Starter
Le Mans Master
Joined: Jul 2005
Posts: 7,121
Likes: 3
From: Shreveport/Bossier Louisiana
St. Jude Donor '08
If you do go with the studs, be prepared to become a contortionist when you put the manifold in. The passenger side manifold will go on with the front four studs in place, but the drivers side manifold will NOT go in place with any in. I was fighting this for a couple of hours last night before giving up. I believe what you're going to have to do is hold the manifold up and start a couple then fights to get the rest of the holes lined up. There simply isn't the clearance on the drivers side.
I have the APR stainless studs, and I will forewarn you, the little tiny allen keys they are sized for like to strip out pretty quick. If this happens, use a second 6pt nut and jamb it and an ARP nut together and tighten the studs down using the jambed nuts.
I have the APR stainless studs, and I will forewarn you, the little tiny allen keys they are sized for like to strip out pretty quick. If this happens, use a second 6pt nut and jamb it and an ARP nut together and tighten the studs down using the jambed nuts.
So I dont have to wait on studs from APS, I can simply use header studs from ARP and they are the same length, etc...?
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Yup. The flange on the APS kit is no thicker than your normal headers IIRC. A standard set of ARP studs will do fine.
Recommendation if you haven't gotten this far: Replace your turbo to downpipe studs with some stainless hardware. When I removed my downpipes last week, I had about half of the nuts come off, and the other half took the studs out of the back of the turbo. The supplied hardware with the APS kit isn't meant for multiple cycling.
Also, VERY closely inspect your oil drain hoses (the rubber ones). Look at the following thread, it's got pics and measurements for new hoses. http://forums.corvetteforum.com/c5-f...oil-lines.html
Last, be very wary of the APS supplied scavenge pump. Mine took a crap at 4K miles (two years on car) and pushed oil through both turbos, crapping the seals out on the drivers side it looks like. I replaced my APS pump with a TurboWerx EXA pump and am not looking back.
Thread Starter
Le Mans Master
Joined: Jul 2005
Posts: 7,121
Likes: 3
From: Shreveport/Bossier Louisiana
St. Jude Donor '08
Taylor @ Dallas Performance tunes it.
Yeah I took my downpipes off the other day and the same thing happened to me. IIRC, this kit has very low milage on it, and it shows bc it is in great shape. Ill keep an eye on the scavenge pump. 
Yup. The flange on the APS kit is no thicker than your normal headers IIRC. A standard set of ARP studs will do fine.
Recommendation if you haven't gotten this far: Replace your turbo to downpipe studs with some stainless hardware. When I removed my downpipes last week, I had about half of the nuts come off, and the other half took the studs out of the back of the turbo. The supplied hardware with the APS kit isn't meant for multiple cycling.
Also, VERY closely inspect your oil drain hoses (the rubber ones). Look at the following thread, it's got pics and measurements for new hoses. http://forums.corvetteforum.com/c5-f...oil-lines.html
Last, be very wary of the APS supplied scavenge pump. Mine took a crap at 4K miles (two years on car) and pushed oil through both turbos, crapping the seals out on the drivers side it looks like. I replaced my APS pump with a TurboWerx EXA pump and am not looking back.
Recommendation if you haven't gotten this far: Replace your turbo to downpipe studs with some stainless hardware. When I removed my downpipes last week, I had about half of the nuts come off, and the other half took the studs out of the back of the turbo. The supplied hardware with the APS kit isn't meant for multiple cycling.
Also, VERY closely inspect your oil drain hoses (the rubber ones). Look at the following thread, it's got pics and measurements for new hoses. http://forums.corvetteforum.com/c5-f...oil-lines.html
Last, be very wary of the APS supplied scavenge pump. Mine took a crap at 4K miles (two years on car) and pushed oil through both turbos, crapping the seals out on the drivers side it looks like. I replaced my APS pump with a TurboWerx EXA pump and am not looking back.