Question abt performance
Thread Starter
Intermediate
Joined: May 2023
Posts: 40
Likes: 4
Question abt performance
I’m planning to do new runners, port the plenum, headers, exhaust, and a CAI to my l98 tpi 1989 is there anything else I should be doing to support this properly, and how much power would this generally add?
Drifting
Joined: Apr 2011
Posts: 1,923
Likes: 439
From: Albuquerque NM
Which upgraded runners? Arizona Speed Marine? Which Headers?
I would skip the intake and put the money into TPIS, Accel, or Edelbrock TPI manifold base, and or some 1.6 full roller rockers.
I have wondered what sort of power those kind of mods would make on an otherwise stock 113 haded L98 car.
Long tube headers and a cat delete, 1.6 full roller rockers, upgraded runners and manifold base... assuming the MAF adjusts well, without a tune I would think maybe 50rwhp so maybe around 265-275rwhp all said and done?
I would skip the intake and put the money into TPIS, Accel, or Edelbrock TPI manifold base, and or some 1.6 full roller rockers.
I have wondered what sort of power those kind of mods would make on an otherwise stock 113 haded L98 car.
Long tube headers and a cat delete, 1.6 full roller rockers, upgraded runners and manifold base... assuming the MAF adjusts well, without a tune I would think maybe 50rwhp so maybe around 265-275rwhp all said and done?
Melting Slicks
Joined: Mar 2002
Posts: 2,873
Likes: 764
From: Sligo PA
I know it's more work but for the money you can't beat a cam and a tune. Add that to your list and it'll feel like a whole different car. Personally I would skip the 1.6 rockers and instead go with a bigger cam. But the 1.6 rockers will add power on a stock cam for sure.
Thread Starter
Intermediate
Joined: May 2023
Posts: 40
Likes: 4
Which upgraded runners? Arizona Speed Marine? Which Headers?
I would skip the intake and put the money into TPIS, Accel, or Edelbrock TPI manifold base, and or some 1.6 full roller rockers.
I have wondered what sort of power those kind of mods would make on an otherwise stock 113 haded L98 car.
Long tube headers and a cat delete, 1.6 full roller rockers, upgraded runners and manifold base... assuming the MAF adjusts well, without a tune I would think maybe 50rwhp so maybe around 265-275rwhp all said and done?
I would skip the intake and put the money into TPIS, Accel, or Edelbrock TPI manifold base, and or some 1.6 full roller rockers.
I have wondered what sort of power those kind of mods would make on an otherwise stock 113 haded L98 car.
Long tube headers and a cat delete, 1.6 full roller rockers, upgraded runners and manifold base... assuming the MAF adjusts well, without a tune I would think maybe 50rwhp so maybe around 265-275rwhp all said and done?
Thread Starter
Intermediate
Joined: May 2023
Posts: 40
Likes: 4
I know it's more work but for the money you can't beat a cam and a tune. Add that to your list and it'll feel like a whole different car. Personally I would skip the 1.6 rockers and instead go with a bigger cam. But the 1.6 rockers will add power on a stock cam for sure.
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Team Owner
Joined: Sep 2001
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
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Could add about 50 crank HP/TQ, especially if port matched on the intake side. Really a better base manifold is whats needed there, the base holds you back.
1.6RR would be fine right now to add along with that. A better cam would help optimize, but that needs a tune, and may need larger injectors based on what the tuner recommended.
If you were sticking with a TPI-style intake, probably something in the 210-212/220ish 050" size would be good.
1.6RR would be fine right now to add along with that. A better cam would help optimize, but that needs a tune, and may need larger injectors based on what the tuner recommended.
If you were sticking with a TPI-style intake, probably something in the 210-212/220ish 050" size would be good.
Thread Starter
Intermediate
Joined: May 2023
Posts: 40
Likes: 4
Could add about 50 crank HP/TQ, especially if port matched on the intake side. Really a better base manifold is whats needed there, the base holds you back.
1.6RR would be fine right now to add along with that. A better cam would help optimize, but that needs a tune, and may need larger injectors based on what the tuner recommended.
If you were sticking with a TPI-style intake, probably something in the 210-212/220ish 050" size would be good.
1.6RR would be fine right now to add along with that. A better cam would help optimize, but that needs a tune, and may need larger injectors based on what the tuner recommended.
If you were sticking with a TPI-style intake, probably something in the 210-212/220ish 050" size would be good.
Melting Slicks
Joined: Mar 2002
Posts: 2,873
Likes: 764
From: Sligo PA
Personally I like the new Summit Racing cams. They are amazing off the shelf cams and they have a lot to choose from. Also they are only around $300 so there tough to beat.
Drifting
Joined: Apr 2011
Posts: 1,923
Likes: 439
From: Albuquerque NM
With 130k miles on the current motor I wouldn't personally do the work to put a cam in it, unless I was just pulling the motor the rebuild it. The cool thing about upgrading the top end right now is later down the line all of those upgraded parts can be used with a rebuilt motor.
I would really hunt for a used Accel, TPIS Big Mouth, or Edelbrock TPI intake manifold base. That upgraded base combined with the Arizona runners, some light port matching work, some long tube headers, and some 1.6 full roller rockers should be pretty solid. 1.6 ratio rockers add lift and some duration, sorta like a cam upgrade, but without the work of going as deeply into the motor.
He'll if you want to you could upgrade heads too while you're at it for more flow, and said heads could be used later on as well.
I would really hunt for a used Accel, TPIS Big Mouth, or Edelbrock TPI intake manifold base. That upgraded base combined with the Arizona runners, some light port matching work, some long tube headers, and some 1.6 full roller rockers should be pretty solid. 1.6 ratio rockers add lift and some duration, sorta like a cam upgrade, but without the work of going as deeply into the motor.
He'll if you want to you could upgrade heads too while you're at it for more flow, and said heads could be used later on as well.
Thread Starter
Intermediate
Joined: May 2023
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Update
After some more research Im planning on doing the TPIS Miniram and Hedman elite extreme-duty 68448 headers to start off, once after that I plan on doing 1.6 RR, heads, and bigger injectors. And a tune ofc
Drifting
Joined: Apr 2011
Posts: 1,923
Likes: 439
From: Albuquerque NM
Hedman Elite 68448 are not bad, I have used several sets. If you have plans for big heads though down the road, some TPIS 1-3/4" headers would fit the exhaust ports better.
A Miniram, upgraded injectors, some 1.6 full roller rockers, long tube headers, and a good tune even on the 113 heads should be solid and get ya up around 275-290rwhp by my guess.
A Miniram, upgraded injectors, some 1.6 full roller rockers, long tube headers, and a good tune even on the 113 heads should be solid and get ya up around 275-290rwhp by my guess.
Team Owner
Joined: Sep 2001
Posts: 62,067
Likes: 1,722
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Thread Starter
Intermediate
Joined: May 2023
Posts: 40
Likes: 4
Could add about 50 crank HP/TQ, especially if port matched on the intake side. Really a better base manifold is whats needed there, the base holds you back.
1.6RR would be fine right now to add along with that. A better cam would help optimize, but that needs a tune, and may need larger injectors based on what the tuner recommended.
If you were sticking with a TPI-style intake, probably something in the 210-212/220ish 050" size would be good.
1.6RR would be fine right now to add along with that. A better cam would help optimize, but that needs a tune, and may need larger injectors based on what the tuner recommended.
If you were sticking with a TPI-style intake, probably something in the 210-212/220ish 050" size would be good.
what base manifold would you recommend?