DP size ? on 408 CI with S91
Originally Posted by DanZ28
Will a 3.5" DP be good enough on a 408 with a S91?
Dan
Dan
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The 4" DP does fit with the factory k-member. I forgot that I tried that out when I designed it. However you will need to trim the top section of the motor mount about 1/4". You will however have more room with the tubular k-frame. Its also easier to install the kit with the k-frame. There is one guy on here with my 4" , but he is waiting for his new turbo. He had it fitted with a S- series turbo and it fit fine he said.
Right off the S-Series Turbo's its a 5" opening...... then neck that down to 3-3.5""???
I wouldnt....
Go the closest you can to 4" at least..... and try not to neck it down after that.....
If ya have to then go to a cut-out 1st then neck it down...
I wouldnt....
Go the closest you can to 4" at least..... and try not to neck it down after that.....
If ya have to then go to a cut-out 1st then neck it down...
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Cool Guys, thanks alot!
Looking to get up in the 1000whp area with the T400
.
Talked to Jose and changed my order from the S88 to S91, looks like the exhaust housings are just waiting to come back from the coaters, then mine should be on the way.
Joel, looks like I will need the 4" DP then all the way to the I-pipe, can you change that on my order please. Can you fit it in to the original time frame or will this put me back a week? I'll maybe just swap it to the UMI K-frame after all. Just want to do this right the first time. BTW, your PM's are full.
Dan
Looking to get up in the 1000whp area with the T400
.Talked to Jose and changed my order from the S88 to S91, looks like the exhaust housings are just waiting to come back from the coaters, then mine should be on the way
.Joel, looks like I will need the 4" DP then all the way to the I-pipe, can you change that on my order please. Can you fit it in to the original time frame or will this put me back a week? I'll maybe just swap it to the UMI K-frame after all. Just want to do this right the first time. BTW, your PM's are full.
Dan
I'm running a 4" dp with Joel's kit and a UMI K. I would highly recommend the k-member, makes life easy working on the car with the extra space it frees up. Here is a link with a few dp pics from my install: https://ls1tech.com/forums/forced-induction/739597-ofi-4-dp-install-pics.html It is a little tight with the 4" dp at the rear of the alt, motor mount, and steering shaft. I did end up slightly flattening the dp at the rear of the alt and the steering shaft to get some more clearance the last time I had it off. It is also a must to either install a heat shield for the alt or wrap the dp to protect the alt from heat. So far 350 miles in 90-100F weather and no problems.
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Originally Posted by DanZ28
Cool Guys, thanks alot!
Looking to get up in the 1000whp area with the T400.
Talked to Jose and changed my order from the S88 to S91, looks like the exhaust housings are just waiting to come back from the coaters, then mine should be on the way.
Joel, looks like I will need the 4" DP then all the way to the I-pipe, can you change that on my order please. Can you fit it in to the original time frame or will this put me back a week? I'll maybe just swap it to the UMI K-frame after all. Just want to do this right the first time. BTW, your PM's are full.
Dan
Looking to get up in the 1000whp area with the T400
.Talked to Jose and changed my order from the S88 to S91, looks like the exhaust housings are just waiting to come back from the coaters, then mine should be on the way
.Joel, looks like I will need the 4" DP then all the way to the I-pipe, can you change that on my order please. Can you fit it in to the original time frame or will this put me back a week? I'll maybe just swap it to the UMI K-frame after all. Just want to do this right the first time. BTW, your PM's are full.
Dan
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Originally Posted by tt427ls1
No it wont change the time frame. It will be 4" all the way back to the "I" pipe.
.I'll give you call.
ozws6, thanks for the link, that helps me visualize how it fits in there now. Do they make a smaller version of our alternator we could use?
Dan
Originally Posted by DanZ28
ozws6, thanks for the link, that helps me visualize how it fits in there now. Do they make a smaller version of our alternator we could use?
Dan
Dan
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Originally Posted by smokinHawk
you guys could always move the alternator up top to the passenger side top
i would.
i would.
I can probably make it work by putting the tensioner back on and getting the right size belt. Does anyone know if the Alt will fit on the passenger head with the OFI kit? I also thought about putting a vacuum pump their...
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Originally Posted by TN94Z
What about the new K-member a coupld of threads down? It looks like it would open it up more so you could fit a bigger DP with no problems.
Originally Posted by DanZ28
I was thinking about that too. Problem is I don't have PS or any other accessories accept the Alt. So right now I just have one short belt from the crank to the Alt.
I can probably make it work by putting the tensioner back on and getting the right size belt. Does anyone know if the Alt will fit on the passenger head with the OFI kit? I also thought about putting a vacuum pump their...
I can probably make it work by putting the tensioner back on and getting the right size belt. Does anyone know if the Alt will fit on the passenger head with the OFI kit? I also thought about putting a vacuum pump their...
if you are you should be able to use on that mounts on the passenger side head with the tensioner there too with a short belt. unless you have the stock water pump, then you might be able if you rig up the tensioner on the driverside.
though if you dont have any accessories i probably would have ran the DP where the AC used to go, thats where i have my 4" downpipe pass through.
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Originally Posted by smokinHawk
are you running an electric water pump?
if you are you should be able to use on that mounts on the passenger side head with the tensioner there too with a short belt. unless you have the stock water pump, then you might be able if you rig up the tensioner on the driverside.
though if you dont have any accessories i probably would have ran the DP where the AC used to go, thats where i have my 4" downpipe pass through.
if you are you should be able to use on that mounts on the passenger side head with the tensioner there too with a short belt. unless you have the stock water pump, then you might be able if you rig up the tensioner on the driverside.
though if you dont have any accessories i probably would have ran the DP where the AC used to go, thats where i have my 4" downpipe pass through.
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Have you guys thought of going with a 4 inch Mufflex intermediate pipe into a 4 inch dynomax ultraflow race muffler or similar? I wouldn't bother necking back down to 3 inch if I could avoid it, 4 inch piping all the way back would work well and support a lot of power
Originally Posted by smokinHawk
you guys could always move the alternator up top to the passenger side top
i would.
i would.
On the 6.0 Iron blocks the alt is located on the top I think on the trucks. I am not sure if it would fit there but I will see.
