Got a 1993 Honda prelude si with a h23a1. I just boosted it and doing the finishing touches. This includes replacing my spark plugs. I have the stock equivalent NGK zfr6f-11 right now. I know the the boosted engine will require a plug change in type and heat range. Any suggestions of a good choice (i would like to stick with NGK since I've had good luck with them but open to suggestions)? Thanks a million in advance!

 

NGK BKR-7E is the commonly-used turbo plug. Here is a link from the Forced Induction FAQ which might shed a little more light on your situation: https://honda-tech.com/forums/forced-induction-16/ngk-spark-plugs-everything-you-ever-wanted-know-more-510127/

 

The number is the heat range and the higher the number the cooler the plug is correct?

 

From Google: http://www.ngksparkplugs.com/tech_su...k_plugs/p2.asp

 

To say a "7" is a normal plug is absurd. If his setup is mild enough it may only need one step colder. It really depends on a lot of factors. You go colder when the plug shows you need to. Lower horsepower typically uses 7s or 8s. Moderate uses 8 to 9s. Higher horsepower builds 9 to 10, and extreme applications 11s+...

To actually be able to help the OP we need more details of the setup and horsepower goals than the vague nothing that was posted.

 

Its a mild setup hoping to gain maybe 100hp. Isn't the "7" one step colder and a good choice? Should I stick with the "zfr" or the "bkr" and drop to the "7"?

 

it really is ALL the same, just a matter of whether or not it is a pre-gapped Z-power or not.

here's a reference chart to review. k?

 

I had a boosted GSR for many years and I only ever used NGK BKR7e plugs at the advice of my tuner. I didnt say it was normal or standard, but that it was common, which it is.

 

I think I'm going to order a set of the "bkr's" and see how it works out. The chart was helpful. Any ideas on*gap preference? I think I'll start at .030 and then check them. I have a msd digital igntion with a msd rotor and cap, large Taylor wires too. Any thoughts?

 

I was told to run a .28-.32 gap, but again it depends on your power level, plug, ignition setup, etc...

 

Start at 0.030" and work your way tighter...

 

I thought I would work my way open more. Why tighter? I am running a msd ignition, plugs wires and cap, if that matters any on gapping....

 

The bigger the gap the harder your ignition has to work to complete the connection (spark). Also, the wider the gap the easier it is for the turbulance to "blow the spark out". If you have "break up" problems, you would go tighter and tighter. Once you start hitting 0.016" - 0.018" it is time to get a better ignition.

 

Bigger gap, longer arc.
When you have forced induction (air) it blows away the arc.
Smaller gap, smaller arc, the arc won't blow out so easy.
If you have ignition break up at a larger gap you'll drop the gap down small increments at a time till the blow out dosent occur.

Edit- took wayy to long to type that lol, neva pretty much said it first

 

When you experience this "blow out " what does it feel or sound like? This is my first turbo car ever so excuse my ignorance but it still seems like you would gap small and go larger till I would experience this "blow out " then back down a notch. So I would know I had the largest gap possible. I understand what everyone is saying but not understanding the method....

 

Then do what you want and reinvent the wheel. Why even ask silly questions? Why don't you just try it and find out for yourself? You act like this is the first time somebody has ever slapped a turbo on a Honda, let alone tried to make your silly low horsepower goals.

 

You'll know ignition breakup when it happens. Car will cut out and miss during a pull

 

Thanks teg, that's what I was looking for, and for the above post yea I know its a bit in depth in something that really isn't a big deal or job.I just wanted to cover everything that way when someone else wants to know its already out there in www, and helps me also. The more knowledge on even the slightest things is what keeps me and a lot of others turning wrenches everyday with results that make us very happy. Even though my car is not going to be making 600hp now, its goin to run perfect! oh and I will have 600hp someday in my street car sir and it's still gona run perfect.