Corvette Forum : DigitalCorvettes.com Corvette Forums banner

1 - 9 of 9 Posts

·
Registered
Joined
·
45 Posts
Discussion Starter #1
When I had my vette tuned I was told by the tuner that a LS6 or LS2 manifold would net me 20 more HP so I went out and found a LS 2 manifold has anyone done this swap. I did not think it all the was through and the new manifold takes a different throttle body 90mm? and the one on my vette is a 78mm .Can anyone tell me how this works .I think that i need to find a throttle body but cant figure out what model ?:WTF
 

·
Premium Member
Joined
·
3,766 Posts
The fuel rails are also different, which is another reason people usually use the LS6 intake instead. It can be done since the port designs are the same, but it is more difficult than just upgrading to the LS6 or an aftermarket version.
 

·
Registered
Joined
·
606 Posts
When I had my vette tuned I was told by the tuner that a LS6 or LS2 manifold would net me 20 more HP so I went out and found a LS 2 manifold has anyone done this swap. I did not think it all the was through and the new manifold takes a different throttle body 90mm? and the one on my vette is a 78mm .Can anyone tell me how this works .I think that i need to find a throttle body but cant figure out what model ?:WTF
Your tuner knows crap as the LS2 intake flows less then a 2001-2004 C5 intake

You do not mention what year your C5 is as ALL 2001 and newer C5s got what some call a LS6 intake manifold and unless the cylinder volume is increased there is not much gain

IMHO I doubt your engine eats more then 600 CFM or air which means the stock MAF, throttlebody and airbridge are just fine which can handle over 750 CFM to 850 CFM. ( over 45 lbs/min)

LS2 manifold requires different mounting of fuel rail and a problem for stock C5 fuel injectors and requires rewiring the connection if using a LS2 TB and if the MAP sensor is now up front then wiring changed for that also
 

·
Registered
Joined
·
45 Posts
Discussion Starter #4
Thank guys

My vette is a 1998,and I see now I have to do alot to use the LS2 manifold not sure how to proceed I know they make a wiring harness to covert LS1 to LS2 TB but I will have to find out what it will take for the fuel rails I will also keep looking for a LS6 manifold for I think it may be allot less work to fit.I do have the aftermarket cold air intake and air bridge . Thanks for all your help
 

·
Registered
Joined
·
609 Posts
Your tuner knows crap as the LS2 intake flows less then a 2001-2004 C5 intake

You do not mention what year your C5 is as ALL 2001 and newer C5s got what some call a LS6 intake manifold and unless the cylinder volume is increased there is not much gain

IMHO I doubt your engine eats more then 600 CFM or air which means the stock MAF, throttlebody and airbridge are just fine which can handle over 750 CFM to 850 CFM. ( over 45 lbs/min)

LS2 manifold requires different mounting of fuel rail and a problem for stock C5 fuel injectors and requires rewiring the connection if using a LS2 TB and if the MAP sensor is now up front then wiring changed for that also

Couldn't of said it better! This guy know his ****:thumbsup:
 

·
Registered
Joined
·
606 Posts
My vette is a 1998,and I see now I have to do alot to use the LS2 manifold not sure how to proceed I know they make a wiring harness to covert LS1 to LS2 TB but I will have to find out what it will take for the fuel rails I will also keep looking for a LS6 manifold for I think it may be allot less work to fit.I do have the aftermarket cold air intake and air bridge . Thanks for all your help
Your engine is stock enough where you can do this cheaper if you want.

Used 2001-2004 intake manifold. ( not just a Z06)
You can tell if old or new intake design, old has part number on passenger side where newer one is on drivers side.

If doing this swap do NOT take off the water cooling purge lines many do but those cooling lines help pull heat out of the end cylinders and newer intake will fit even with those metal lines still on.

Swap is like a hour of your time.
Use stock throttlebody.

98 stock MAF is 75 mm which can handle 750 CFM airmass

You can switch to a 2001-2004 MAF which is 85 mm or 850 CFM but you have to do a wiring connector pinout change as the 75 mm is a 3 wire,
the IAT sensor is in airbridge where the 85 mm MAF is a 5 wire as IAT is built into the MAF.
 

·
Registered
Joined
·
114 Posts
Y
If doing this swap do NOT take off the water cooling purge lines many do but those cooling lines help pull heat out of the end cylinders and newer intake will fit even with those metal lines still on.
All of the install write ups say that the flat based LS6 intake will not clear the water pipes that run under the LS1 intake. Can anyone confirm that it actually does fit without water line mods.
 

·
Registered
Joined
·
606 Posts
All of the install write ups say that the flat based LS6 intake will not clear the water pipes that run under the LS1 intake. Can anyone confirm that it actually does fit without water line mods.
I have installed 2001 newer intake on many LS1s and they fit.

On bottom of newer intake is some thin plastic ribs that can be sanded down just a bit and intake will fit fine while leaving the cooling lines in place.
GM in racing C5R found out the hard way that in removing those cooling lines that the end cylinders get too hot/lean as the cooling helps pull the heat of of the heads.

Those lines also help purge air out of the system so just leave them in.
 

·
Registered
Joined
·
114 Posts
I have installed 2001 newer intake on many LS1s and they fit.

On bottom of newer intake is some thin plastic ribs that can be sanded down just a bit and intake will fit fine while leaving the cooling lines in place.
GM in racing C5R found out the hard way that in removing those cooling lines that the end cylinders get too hot/lean as the cooling helps pull the heat of of the heads.

Those lines also help purge air out of the system so just leave them in.
That is good to know, I really didnt want to mess with coolant line modification. I found a site that is selling ported LS6 intakes for what seems to be a pretty decent price.
 
1 - 9 of 9 Posts
Top