I want to copy cat your 4.8 GM build!
01-06-2015, 11:29 AM
#1
I want to copy cat your 4.8 GM build!
I am about to start my project and have decided to go with a 4.8 GM motor. I have ZERO v8 experience and get lost when numbers of heads and cams get thrown around. What I want is to copy cat the build of someone that is making good power reliably out of a 4.8. What heads, cams, bolt ons should I use? The motor will stay stock bottom end for now since the motor I am looking to get has only 37k miles on it.
Help me fill in the blanks please:
1990 NA Miata w/ V8R kit
Motor: 4.8 (2012 GM Truck)
Heads: _________?
Cam: __________?
Other bolt ons _____________________________________?
Trans: __________? T56? or is there something better bang for the buck?
Rear end: ___________ ? Ford 8.8 Tbird or Cobra
I know that I need a lot more to complete the project, these major components are my main concern at this point.
Help me fill in the blanks please:
1990 NA Miata w/ V8R kit
Motor: 4.8 (2012 GM Truck)
Heads: _________?
Cam: __________?
Other bolt ons _____________________________________?
Trans: __________? T56? or is there something better bang for the buck?
Rear end: ___________ ? Ford 8.8 Tbird or Cobra
I know that I need a lot more to complete the project, these major components are my main concern at this point.
01-06-2015, 03:45 PM
#2
V8 Miata Follower
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Just deck the heads to result in 11:1 SCR, add beehive springs, LS6 CAM & an LS6 intake. LT headers (no larger than 1-5/8" primaries & 1-1/2" are OK). Rear end, 8.8 w/3.73 & a Cobra cover will help to wake things up a bit. T-56 trans, 25% under drive pulley.
Your PCM will need to be tuned for the upgrades.
What's noted here is a strong, sound, budget oriented arrangement. There are more expensive options that will yield a little more. Don't get talked into a FAST intake. The intake runners are too large for a 4.8 NA. This will slow the air down & reduce power.
Your PCM will need to be tuned for the upgrades.
What's noted here is a strong, sound, budget oriented arrangement. There are more expensive options that will yield a little more. Don't get talked into a FAST intake. The intake runners are too large for a 4.8 NA. This will slow the air down & reduce power.
01-06-2015, 07:24 PM
#3
V8 Miata Follower
add a turbo or 2
919hp/880tq stock bottom end 4.8 ...... - TCG
http://www.hotrod.com/how-to/engine/...g-bang-theory/
919hp/880tq stock bottom end 4.8 ...... - TCG
http://www.hotrod.com/how-to/engine/...g-bang-theory/
Last edited by mazdaspeedmiata; 01-06-2015 at 07:30 PM.
01-07-2015, 11:01 AM
#4
Wow! That's what I was looking for. Thank you!
What kind of horsepower are we talkin with this set up?
What kind of horsepower are we talkin with this set up?
Just deck the heads to result in 11:1 SCR, add beehive springs, LS6 CAM & an LS6 intake. LT headers (no larger than 1-5/8" primaries & 1-1/2" are OK). Rear end, 8.8 w/3.73 & a Cobra cover will help to wake things up a bit. T-56 trans, 25% under drive pulley.
Your PCM will need to be tuned for the upgrades.
What's noted here is a strong, sound, budget oriented arrangement. There are more expensive options that will yield a little more. Don't get talked into a FAST intake. The intake runners are too large for a 4.8 NA. This will slow the air down & reduce power.
Your PCM will need to be tuned for the upgrades.
What's noted here is a strong, sound, budget oriented arrangement. There are more expensive options that will yield a little more. Don't get talked into a FAST intake. The intake runners are too large for a 4.8 NA. This will slow the air down & reduce power.
01-07-2015, 01:40 PM
#6
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5.3 guys w/ this combo make in the 300 RWHP range. So, 4.8 would expect it to be in the area of 270 RWHP. The key will be to include the LT headers. If you skimp & don't use long tubes, expect the power to be lower.
01-07-2015, 02:58 PM
#7
Jim Stainer
LOL you crack me up Gator!
I'm a really big fan of the ASA cam. The Howards version is much cheaper than GMPP and a little better ramp profile. The + is a nice bump in HP (depends on what you read from 40 to 90 pick anything in between) it's very easy on the valve train so no need to change a bunch of parts there and it's got great idle note.
I'm a really big fan of the ASA cam. The Howards version is much cheaper than GMPP and a little better ramp profile. The + is a nice bump in HP (depends on what you read from 40 to 90 pick anything in between) it's very easy on the valve train so no need to change a bunch of parts there and it's got great idle note.
01-07-2015, 06:55 PM
#9
V8 Miata Fanatic
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