Quad throttle bodies for a b16b

[intacivic16v]

Hey guys i am interested to see if any one here has put an after market or custom QTB set up on there cars? I saw in an issue of auto sallon that they were testing a set up from the states out on a N/A B18CR engine. It made around 12kw gains all the way from 3000 to 8500rpm.. but it was said that it would need constant tuning.. didn't really specify if that was for the first tune to get it running well, or due to them going out of tune all the time, or due to climate change with air pressure etc.

It would be great to talk to someone that has gone through this and knows a little tech about it.

I hillclimb and circuit race my car and i want to keep it N/A and 1600 due to class restictions, so i figure that QTB's may be a viable option.

[vinnY]

barefoot's infamous thread (http://www.ozhonda.com/forum/showthread.php?t=55347&highlight=itb%2A)
http://ozhonda.com/forum/showthread.php?t=52043
http://www.ozhonda.com/forum/showthread.php?t=77096&highlight=itb%2A
comparison between types setups (http://www.ozhonda.com/forum/showthread.php?t=86662&highlight=itb%2A)
talk about obx ones (http://www.ozhonda.com/forum/showthread.php?t=88974&highlight=itb%2A)
itb troubles on a b18 (http://www.ozhonda.com/forum/showthread.php?t=89033&highlight=itb%2A)
some info on tuning? (http://www.ozhonda.com/forum/showthread.php?t=93511&highlight=itb%2A)

:)

[TODA AU]

I hillclimb and circuit race my car and i want to keep it N/A and 1600 due to class restictions, so i figure that QTB's may be a viable option.

They can be a viable option, but they are best combined with higher compression, cams, bang-on exhaust etc.
If everything is up to scratch & you can afford a decent set of quads with a good airbox & CAI feed...
Combine this with altered head porting to suit the quads...
& you're on a very good thing...
If you only add quads & suck air from the back of the engine bay without an airbox.
All you will acheive is a sizable hole in your pocket with not real performance benifit.
(Read as there is not much meat in that pie with the bonnet shut)

As for the need for constant tuning,
If the thing is tuned correctly & set up well, you will have no such issue.

On a B16A, same engine combination with CAI, ITR throttle & plenum vs same engine combination + quads with airbox & cai feed
Both engines tuned for best output,
The addition of quads & ascociated components should see a gain of 15~18kw at the wheels @ 5500rpm
Peak power gain is less @ 5~7kw
This asumes the original engine combination is sound & able to produce decent power in the 1st place.

[intacivic16v]

They can be a viable option, but they are best combined with higher compression, cams, bang-on exhaust etc.
If everything is up to scratch & you can afford a decent set of quads with a good airbox & CAI feed...
Combine this with altered head porting to suit the quads...
& you're on a very good thing...
If you only add quads & suck air from the back of the engine bay without an airbox.
All you will acheive is a sizable hole in your pocket with not real performance benifit.
(Read as there is not much meat in that pie with the bonnet shut)

As for the need for constant tuning,
If the thing is tuned correctly & set up well, you will have no such issue.

On a B16A, same engine combination with CAI, ITR throttle & plenum vs same engine combination + quads with airbox & cai feed
Both engines tuned for best output,
The addition of quads & ascociated components should see a gain of 15~18kw at the wheels @ 5500rpm
Peak power gain is less @ 5~7kw
This asumes the original engine combination is sound & able to produce decent power in the 1st place.


thanks heaps mate. i figured i may as well let you know a little about the car then.
Its a b16a block with B16B type r pistons, we estimated 11.25:1 compression, full type r head with a set of descent aftermarket extractors, and a microtec computer. 156hp atw's.

If i ended up going ahead with it i was going to build some sort of air ducting system as well. because i have heard that before and it sounds like a very logical idea.

The exhaust system from the extractors back isn't the best and i would think that i would have to change that as well, its 2 1/4 but squash bends, so it is restricting it a little.

With the set up that i have now to think that i would need to make move engine modification i.e cams etc? what other things would i need to do? and how much do you think that it would end up costing to get it done right??

Thanks heaps. Brian

[Benson]

ITB's are the way too go.. even with a stock motor, itb's will still work... dyno figure might not look that good, but wait on the track...

Our set-up isnt making great dyno figure, but on the track it still haul ass and beat with cars with higher kw numbers on the dyno..

conclusion, itb's FTW!

[intacivic16v]

Yeah the car may as well be a full track car anyway. It goes throught the fuel heaps now

[TODA AU]

thanks heaps mate. i figured i may as well let you know a little about the car then.
Its a b16a block with B16B type r pistons, we estimated 11.25:1 compression, full type r head with a set of descent aftermarket extractors, and a microtec computer. 156hp atw's.

If i ended up going ahead with it i was going to build some sort of air ducting system as well. because i have heard that before and it sounds like a very logical idea.

The exhaust system from the extractors back isn't the best and i would think that i would have to change that as well, its 2 1/4 but squash bends, so it is restricting it a little.

With the set up that i have now to think that i would need to make move engine modification i.e cams etc? what other things would i need to do? and how much do you think that it would end up costing to get it done right??

Thanks heaps. Brian
Sorry about the delay replying, this one was always going to take a while.
If you do get quads,
Buy ones where a box of some sort is available to suit.
Be that TODA, Jenvey or TWM. All have air boxes that work.
Using one of these systems will take a lot of the head ache out of it for you.
The other things you aught not forget is the need for new fuel lines & fittings.
Depending on the quality use will also affect your budget & the overall appearance of the engine when completed.

To get the most from the quads, the exhaust system has to be spot on.
Any issues here will be magnified when the quads are fitted.
This is even more-so when the compression is increased & larger cams are used.

Regarding making changes to your current engine combination,
Though you can fit the quads now & have it tuned,
In my opinion, I wouldn’t until you’ve got the most out of the engine using the single throttle, plenum system.
That is, though there is an improvement in performance & response, there is better value in performance for dollar spent in cams, compression & head work.
I can’t comment on the headers you have, but these will make or break the whole combination.
As for the total cost you’d be looking at, well that’s really up to you.
Set yourself a realistic budget & try & stick to it.
Don’t go into it with an open ended budget as you’ll only end up lighter in the pocket.
To get the most out of it, you’ll need to have a combination that works.
Simply picking what looks to be the best cherries & putting them all together, doesn’t always work.
So plan the build to include all of the component’s you’ll need so there are no nasty surprises.
If in doubt, go & see some of the shops that are experienced in this sort of tuning.

Further to this, the size of the throttles used has a big impact on the response & power delivery & total output of the engine.
As a rule of thumb, you can pretty much say, the larger the butterfly, the higher the peak power.
At the expense of low end & response
Or the smaller the throttle, the better the response, mid range & torque
For a B16A – 42~45mm is about right.
My self, I favour the larger size for better top end.

As a side note, when using TODA, Jenvey or TWM quads,
The head porting should be changed to suit the new manifold for best results.
This will improve response & power throughout the rev range.

Hope that helps
Cheers

Adrian