New Alum. heads...port height with CMI headers? (Pic)
#1
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New Alum. heads...port height with CMI headers? (Pic)
My plan is to pull the heads off my 575sci to replace the head gaskets and then swap out the heads with AFRs. The exhaust port height is .3" higher than the stock heads. Question is will there be enough deflection in the CMI joints to allow for the .3" difference in height?
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My plan is to pull the heads off my 575sci to replace the head gaskets and then swap out the heads with AFRs. The exhaust port height is .3" higher than the stock heads. Question is will there be enough deflection in the CMI joints to allow for the .3" difference in height?
Dustin
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That just might change my thinking. It seems to be very fat right now everything being stock. So...even with the stock cam these heads are going to flow enough to lean it down and change the manifold pressure? My plan was to pull the motor next year and totally go through it and change the cam. At that point have the ECM worked...
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That just might change my thinking. It seems to be very fat right now everything being stock. So...even with the stock cam these heads are going to flow enough to lean it down and change the manifold pressure? My plan was to pull the motor next year and totally go through it and change the cam. At that point have the ECM worked...
You can bolt the AFR's on, I think it will idle and run, but it won't be right, and with it being as rich as it is, it might make less power because the boost will drop to maybe 1psi, and there will be very little temp in those heads. Of course, I would install the 3" pulley and shorter belt, get some pressure in that motor and it will probably come alive. If you get the af meter, it would help, then someone could help modify the ECM for you off of your info.
Thanks,
Dustin
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Just so happens I spoke with CMI yesterday as I just purchased two sets of Sport Tubes. Dave from CMI said that AFRs will add 1/4 width per side and about 1/8 in height.
Probably not an issue.
Dave
Probably not an issue.
Dave