How much and where next!
Thread Starter
Intermediate
Joined: Jul 2004
Posts: 40
Likes: 0
How much and where next!
I've got 1990 Convertible, mods so far; tubular headers, 21/2" full twin exhaust system, de-catted, easy flowing mufflers (sounds great!), K&N air cleaner with open lid, frisbee removed, air foil-160 degree stat-hypertech chip (yup, I know!), so couple of questions, how much extra hp have the mods given so far and what would you recommend would be the next steps in boosting the power?
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
I would guess that you are not making a little over 300chp with those mods.
What's next depends on where you want to go, i.e. street only, street/strip, etc.
What is your ultimate power goal.
Is it a 6-speed or A4?
What gears?
The next big $$ power adders would be:
-heads
-cam & valve train
-intake
-torque converter & tranny
-gears
-dyno tuning
It is likely that you could now benefit from installing an AFPR and increasing fuel pressure maybe 4-5psi over the current stock reading at idle with vacuum line disconnected.
What's next depends on where you want to go, i.e. street only, street/strip, etc.
What is your ultimate power goal.
Is it a 6-speed or A4?
What gears?
The next big $$ power adders would be:
-heads
-cam & valve train
-intake
-torque converter & tranny
-gears
-dyno tuning
It is likely that you could now benefit from installing an AFPR and increasing fuel pressure maybe 4-5psi over the current stock reading at idle with vacuum line disconnected.
Advanced
Joined: Mar 2005
Posts: 97
Likes: 0
I'm loving my 90 6 spd convert 3.33...
One mod I'm loving is a billet aluminum shift **** (I had to make it on a lathe because I couldn't find a good one for sale) and a replacement spring to decrease rear lock out ring force. The original shift **** was worn, and the underlying plastic was spongy. Now it's dreamy and feels much more precise, like my S2000 used to. And the lock-out ring is easy instead of irritating to lift.
I also swapped my front brakes for J55 13" units, trying desperately to improve brake feel - afraid I was spoiled by the S2000...
One mod I'm loving is a billet aluminum shift **** (I had to make it on a lathe because I couldn't find a good one for sale) and a replacement spring to decrease rear lock out ring force. The original shift **** was worn, and the underlying plastic was spongy. Now it's dreamy and feels much more precise, like my S2000 used to. And the lock-out ring is easy instead of irritating to lift.
I also swapped my front brakes for J55 13" units, trying desperately to improve brake feel - afraid I was spoiled by the S2000...
Last edited by ls5454; Apr 9, 2005 at 01:49 PM.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Originally Posted by 1990C4 ConvertUK
AIR pump has been removed too, forgot to mention, duh! Any worth in getting a high output distributor?
Jake
Drifting
Joined: Aug 2004
Posts: 1,830
Likes: 1
From: atlanta Georgia
6 spd.....
get 3.73s or 3.90s or 4.10s
get a bigger cam, 1.6 rrs and matching springs...
find someone local to port heads and then get a cutom tune!
looking at about 2 grand plus install unless you install your self!
get 3.73s or 3.90s or 4.10s
get a bigger cam, 1.6 rrs and matching springs...
find someone local to port heads and then get a cutom tune!
looking at about 2 grand plus install unless you install your self!
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Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Originally Posted by 1990C4 ConvertUK
I've got 1990 Convertible, mods so far; tubular headers, 21/2" full twin exhaust system, de-catted, easy flowing mufflers (sounds great!), K&N air cleaner with open lid, frisbee removed, air foil-160 degree stat-hypertech chip (yup, I know!), so couple of questions, how much extra hp have the mods given so far and what would you recommend would be the next steps in boosting the power?
Cylinder heads
Camshaft
Compression.
Those are the three main things that increase engine power.
Some like to say gears/converters; but those only increase acceleration, not engine power. When an engine's on the dyno, gears and converters aren't even attached.
Exhaust is important too (I see you've already gone that route), but a full bore exhaust system usually only gives 10/15 hp increase, tops. In fact I read one mag article where over $1,100 was spent on a bang-wiz exhaust setup and only 12 or so hp gain was realized. Satellite programs, like HP TV, regularly show the same results when headers and a full FlowMaster system are installed and the car dynoed.
As an example, the same money spent on a set of aftermarket heads will give you more than three times that much power increase
It's always been the three 'C's.
Jake