Improving low end torque

[phantomcow2]

What are some modifications one can make to their CB7 to improve low end torque? My goal for my '93 lx 5sp is achieving maximum reliability and fuel economy. Since most of my driving is done below 3000rpm, I'm interested in what would improve low end torque. My understanding is that most aftermarket exhaust systems and intake manifolds will actually reduce low end, antithetical to my goals.

Currently I have a few modifications:
AEM Short ram intake
Cheap, Ebay 421 headers that I installed after my stock flex pipe failed 2 years ago.

[psyclist]

i found the best way to improve low end torque, was when i installed the H23 intake, i already had the megan 4-2-1 header and magnaflow exhaust, as well as my SRI. it ties everything in and opens it up quite a bit.

the next thing is shave the head to up compression, that will help the low end as well

[owequitit]

What are some modifications one can make to their CB7 to improve low end torque? My goal for my '93 lx 5sp is achieving maximum reliability and fuel economy. Since most of my driving is done below 3000rpm, I'm interested in what would improve low end torque. My understanding is that most aftermarket exhaust systems and intake manifolds will actually reduce low end, antithetical to my goals.

Currently I have a few modifications:
AEM Short ram intake
Cheap, Ebay 421 headers that I installed after my stock flex pipe failed 2 years ago.

get a high flow cat and catback (in many cases they can actually improve power all the way through if you don't get too big.

swap an F22A6 92-93 EX intake manifold and ECU, and the cam from that same engine. Hook up the secondary butterflies normally. Put an H22 or H23 plenum and throttle body on it. That makes a HUGE difference on these engines and it is dirt cheap.

[Granite CB7]

^definitely. Might aswell get a whole intake mani. off an H23A1, since the runners are 1/2" longer than F22A6, plus you'd have the H-series plenum and t/b right off the bat. Also, adding length to the IM will yield gains in the low end. You can do this by adding an extra gutted IAB plate (or Blacktrax spacer) to your IM setup.

[mightyaccord]

get a high flow cat and catback (in many cases they can actually improve power all the way through if you don't get too big.

swap an F22A6 92-93 EX intake manifold and ECU, and the cam from that same engine. Hook up the secondary butterflies normally. Put an H22 or H23 plenum and throttle body on it. That makes a HUGE difference on these engines and it is dirt cheap.

how big of an exhaust piping do you for:
a)f22a6
b)h22

*i heard for the h22, its better to go with 2.5"? but is this better for high end power? would 2.25" be better for low end or would that cause too much back pressure?

[mightyaccord]

btw, sorry, i am know way trying to jack the thread, i just happen to get curious to your reply

[owequitit]

how big of an exhaust piping do you for:
a)f22a6
b)h22

*i heard for the h22, its better to go with 2.5"? but is this better for high end power? would 2.25" be better for low end or would that cause too much back pressure?

With a bolt on F22, such as the one suggested above, I would stick between 2.25" and 2.5". With an H22, I would probably start at 2.5" and go up from there. With much more than bolt ons, the H22 starts to benefit from 3" exhaust. One of the biggest mistakes I see people make with Hondas is not letting them breathe properly. Oddly, in many cases, a slightly large exhaust helps the bottom end more than you would believe.

[wed3k]

lightening up the rotating mass and help the engine rev a little quicker which will "seem" that the engine will have more torque.

[Jonas]

the more air you flow via larger intake and exhaust, the higher you push the powerband in the rpm range. increasing flow will decrease low end torque, but increase overall power production.

the best ways to get low end power are more advanced than simple bolt-ons. swap in a larger engine (h23, k24, j32 ) install a moderately sized turbo (too large will give a high powerband and a soggy bottom end, too small will damage your engine), or install a supercharger (the king of low end response, but there are no direct bolt-on kits for our cars)

[kapone]

the more air you flow via larger intake and exhaust, the higher you push the powerband in the rpm range. increasing flow will decrease low end torque, but increase overall power production.

the best ways to get low end power are more advanced than simple bolt-ons. swap in a larger engine (h23, k24, j32 ) install a moderately sized turbo (too large will give a high powerband and a soggy bottom end, too small will damage your engine), or install a supercharger (the king of low end response, but there are no direct bolt-on kits for our cars)

can you elaborate on this ... i assumed that a small turbo would help with low end power because of the almost instant response ...

[owequitit]

the more air you flow via larger intake and exhaust, the higher you push the powerband in the rpm range. increasing flow will decrease low end torque, but increase overall power production.

the best ways to get low end power are more advanced than simple bolt-ons. swap in a larger engine (h23, k24, j32 ) install a moderately sized turbo (too large will give a high powerband and a soggy bottom end, too small will damage your engine), or install a supercharger (the king of low end response, but there are no direct bolt-on kits for our cars)

That is not entirely true. Many cars (Hondas included) show a gain through the entire power band with a properly sized exhaust.

[Jonas]

can you elaborate on this ... i assumed that a small turbo would help with low end power because of the almost instant response ...

yes a small turbo will certainly help low end power. however, small turbos produce a LOT of heat. heat kills engines.





and yes it is true that a gain can be had throughout the rpm range. however, in general, opening things up moves the powerband up through the range. to retain low end power you should understand how things work and plan accordingly