Quad Throttles What Are The Gains??

[GSi_PSi]

ITB's provide great midrange hp/torque, ie imo great for tracking the car.
For Overall Peak power a Edlebrock Intake manifold+Cold Air Fed Airbox Combo will come out on top vs ITB's

[trism]

Heres a quick thing about temps.

When i had my corolla, AE92 with a 20v Blacktop 4AGE, factory quads for those who dont know, i decided to do an experiment.

in the height of summer, mid December, i got myself one of these




literally that exact one. its got a temp sensor in it, and one of a 2m long lead, so you can get outside and inside car temps.

What i did, was i took the plenum chamber/airbox off, so it was running open trumpets, pointed at the firewall, and i got the temp sensor, and i mounted it, so it was hanging off the strut brace, right where they drew the air from.

ambient temp was about 35 degrees, the sensor under the bonnet was reading off the scale, maxed it out at like, 70degrees.

so i put the plenum back on, and ran a pipe straight from it down to under the front bar, pointing forwards., with the sensor suspended inside the plenum.

i was seeing temps of 30 degrees. It woulda been showing under ambient because the air rushing past the sensor, so the engine was drawing ambient air. Thats a massive difference, and something i tell people every time i see them with open ITBs.

The best part was the winter test but. Same set up, under bonnet temps were about 50degrees, but the shocking part was with a full intake, drawing fresh air, ambient temp was 12 degrees, the sensor was reading 5degrees!

And at night, i was getting negative temperatures inside the plenum. That is some seriously dense air!

point being, as much as ITBs may have the coolest sound in the world when run open, it always benefits running an airbox with a proper cold air intake.

[dougie_504]

So basically any CAI, or enclosed intake + air feed, or ITB's + enclosure + air feed = win?

I always thought so myself, but didn't realise the temperature difference would be that massive.


My mechanic doesn't like the idea of the air-feed at the front of the bumper during summer because he thinks that the bitumen of the road absorbs/releases too much heat which is sucked it at the front of the car. As if that's not better than engine-bay temps...

[Bludger]

http://www.ozhonda.com/forum/showthr...=1#post2380387

[trism]

So basically any CAI, or enclosed intake + air feed, or ITB's + enclosure + air feed = win?

I always thought so myself, but didn't realise the temperature difference would be that massive.


My mechanic doesn't like the idea of the air-feed at the front of the bumper during summer because he thinks that the bitumen of the road absorbs/releases too much heat which is sucked it at the front of the car. As if that's not better than engine-bay temps...

Not just enclosing ITBs, but any intake.

If you have one of these "short ram intake" where the pod filter just sits in place of the factory airbox, youre still gonna be seeing temps that high. A proper CAI, that draws proper fresh cold air, from outside the engine bay is gonna make so much difference.

with regards to too much heat off the road, my tests didnt show shit of a result. Remember, when youre driving along, your constantly moving through the air, its not like youve got a kitchen hotplate positioned under the intake lol

[dougie_504]

He's old-school and just doesn't like pods IMO.

I'm all for relocating into the hole above wheel well at the very least. Ideally I'd like a fab'd aluminium box so bring the filter closer to the TB though and an air-feed from bumper. Enclosed ITB's would be awesome...mmmm

[p3akin]

sorry to go off topic but, whats the power/torque difference in the 45mm and 50mm throttle valve??

[Bludger]

sorry to go off topic but, whats the power/torque difference in the 45mm and 50mm throttle valve??

Length of intake runners dictates what rpm range power band comes on.

[p3akin]

thanks for that

[GSi_PSi]

1+ bludger never knew that



You must spread some Reputation around before giving it to Bludger again.

[TODA AU]

What kind of compression and capacity would you recommend?

Compression – 11.5 : 1 +
Capacity – An increase is helpful but not 100% necessary.
Though you will still have useful gains at std capacity, an increase amplify the result.
My personal favourite is 1979cc B18C – 85.00 bore x 87.2mm stroke

sorry to go off topic but, whats the power/torque difference in the 45mm and 50mm throttle valve??

45mm throttles are better suited to engines with 1600cc to 1900cc
50mm throttles are best suited to engines with approx. 2L capacity over
Smaller throttles offer improved airspeed & better response/midrange

Length of intake runners dictates what rpm range power band comes on.

The following factors interact to dictate the power band & it’s characteristics.
Runner length, plenum/airbox volume, port size & shape, compression ratio, camshaft selection,
Exhaust port size & shape, header selection.
When the combination is correct, then the intake length can be altered with predictable results.
The reverse is true of less than ideal combinations.

The other trap many people fall into is over caming the engine.

[Bludger]

Compression – 11.5 : 1 +
Capacity – An increase is helpful but not 100% necessary.
Though you will still have useful gains at std capacity, an increase amplify the result.
My personal favourite is 1979cc B18C – 85.00 bore x 87.2mm stroke


45mm throttles are better suited to engines with 1600cc to 1900cc
50mm throttles are best suited to engines with approx. 2L capacity over
Smaller throttles offer improved airspeed & better response/midrange


The following factors interact to dictate the power band & it’s characteristics.
Runner length, plenum/airbox volume, port size & shape, compression ratio, camshaft selection,
Exhaust port size & shape, header selection.
When the combination is correct, then the intake length can be altered with predictable results.
The reverse is true of less than ideal combinations.

The other trap many people fall into is over caming the engine.

"I want the biggest"

lol