Pea Shooter Chronicles (first gen honda insight mods)

[A.K. Boomer]

Boy this car is finicky

So iv made pretty good progress with my preheat system but am waiting on my preheat hose which no auto store could get the one I wanted but guess what? home depot could so it should be here next couple days, just in time for the warmer weather lol

Anyways --- getting to know this thing a little better and since it's just a 1 liter im not only looking for efficiency gains but also an extra pony or two if it does not effect anything,

so while doing this other stuff I seen the throttle body and could not help but notice the two large button head screws holding the plate in it's place --- right in the smallest section of the bore --- it's a factor --------- if there's anyplace where power is being lost always think about intake restrictions, they are so critical as it's the single biggest gain area if they are impeding flow in any way...

Pic is plate wide open;




So --- I set out to remove said screws - easier said then done as the other side is "stamped" on the threads to prevent this (so they do not fall in the engine) in fact you can see this in the first pic, trick is to just drill the heads off and they will "drill spin" in a ways and then you can get some needle nose on them and get them out that side, Do one at a time so the plate never shifts - always keep one tight,,, after that a carbide countersink and then grind to size and install (WITH LOCTITE!!!) some flat countersink allen heads...



WOW what a diff --- this car redlines at 6,000 rpm's but would start to fall on it's face at about 5,500 --- and now - even a mile high she pulls to 6 and pulls up the entire way noticeably better... any little gains in this area amount to being compounded because additional air flow is increased power...


The thing is - is between doing this and cleaning the throttle body from surface carbon it tripped up my mixture into going too lean, It seams to have taken a bunch of restarts for the computer to re-calibrate things - but now all is good and back to normal....

[A.K. Boomer]

The other surprise in the Pea shooter was remember when I posted My tercel mod with the throttle cam I modified to be progressive, just was an idea I had so you don't overshoot your mark and keep you in the sweet spot --- lots of pedal travel just off idle to create very little plate movement --- here's my modified version of the tercels

Well - I did that maybe like a decade ago --- and guess what? honda beat me to it in the year 2000...



pic below is at idle;

;

now full throttle



Makes allot of sense when your feathering the throttle at mild cruise speeds,,, or just "granpa-ing" it around town,,, having a real time mileage graph really shows this effect...

[JRouche]

Boy this car is finicky

So --- I set out to remove said screws - easier said then done

You should know I broke my teeth (cherry) for my first rebuild on a Honda engine. Car wise. Briggs and Stratton was my first.

I love the Honda engines. Went through a few.

I like the fix you did. I call it a fix because that should have been built like what you did. JR

Did I show you the pics of my new lexus, 6 banger engine top half I did, no schematics. LOL.

Yeah, Idiots decided to put two injectors in the top. Who knew? Not me. hahaaa. It went back together just fine as did my ol BS engines. Label everything is all I can say. JR

[A.K. Boomer]

JR, Is your Lexus direct injection gas? if so that's why the two injectors in the top, it's a "hybrid" injector system designed to keep the backside of the intake valves clean, one of the problems with going direct injection gas is that you no longer have fuel washing over certain parts to keep them clean yet with valve overlap and certain RPM ranges creating slight backflush you can get combustion carbon build up,

also intake valves are mostly at high vacuum where the stems are and they can suck small amounts of oil and bake it on the valve's backside and ruin flow so some manufacturers use "inboard" injectors once in awhile at certain engine modes when they can...

Yeah iv done hundreds of subie/honda and toyota rebuilds --- sometimes i'll stand back and look at the workbench and it's all stacked on top of itself lol only order im concerned with is that all rockers or shim and buckets match the cam lobe they belong too - that all pistons (if re-used) get stuffed back into their same bores and things like that (parts that are re-used get fitted to their counterparts) --- also that I do not "box myself in" during the assembly process --- with today's complexities that can happen and then you have an "oh fuque" moment... so as far as standing back and seeing what most people would call a total mess Im really not intimidated by it at all - know where I have to start and it's surprising when you go that route how the bench starts clearing up along the way, first thing I do before disassembly is stamp the piston tops with their #... same with any other caps (rods and mains) that do not already have number markings...

I hear you on honda should have done what I did while building the throttle body,,, but my guess is they weighed it out and it would have cost a few extra steps so just built the entire TB slightly larger to handle the flow,,, I bet the car pulls nicely up to 6,000 rpm's @ sea level with 14.7 psi but im a mile high here and drop just over 3 psi, that's substantial and notice differences with allot of cars taking a performance hit throughout their range and in fact unless turbo'ed or super'ed ALL take a big hit at full throttle high rpm's where they would normally be making very good power...
it's one thing to just plain start out with thinner air and less oxygen, but then there's also volumetric efficiencies that come into play with trying to get said thinner air to move from point A to point B with less pressure behind it... now reduce the time frame with higher RPM's and things start to really show up --- not the first time iv used the expression "falling on it's face" to describe an engines performance or "flow dynamics" @ higher RPM's, in fact My Del-Sol did the same thing --- redline is 7,200 rpms and things started dropping off around 6,750,,,

but with extensive intake and exhaust mods and also some mild porting and polishing she pulls all the way up till the rev limiter kicks in @ 7,450 RPM's...

[dian]

now you need a velocity stack.

[A.K. Boomer]

now you need a velocity stack.

Maybe Sid will loan me one of his, very nice work and im sure just one individual that he uses for a single cylinder would take care of all three of the pea shooters lol

[sid pileski]

I do have an extra day one!
haha
When I was making my throttle bodies, I had to make all the shafts and the brass butterflies. My butterflies are screwed onto the shafts like your Honda. I suppose they have the same flow restrictions. But I don’t seem to be notice!

Sid

[A.K. Boomer]

Well - had a little time today to finish the "blend box" so thought id post a few pics...

this is the "apparatus" that I removed that came with the vehicle --- note the "dead end" tank attached strictly for keeping intake sound to a dead minimum --- I love intake noise, why would anyone ever try to dampen that -- cars so quite I can barely tell it's running at redline... seriously, have to look at the tach to know when to shift...

just got things resting kinda where they used to go except the dead end usually resides under the drivers fender well up front...



So - this is the pic of the greatly modified blend unit, it's all hacksawed off of a round type air cleaner canister/plenum for a carb engine...


I was going to paint it - but why bother - I know it looks like a POS but don't really care just want function...





This is unit installed on the vehicle --- minimally invasive as I don't want to drill holes in the pea shooter so just want clamp on stuff that can be easily removed ...

If you follow the snorkel down you can see the flange taking off to the left that will be picking up the heat from the "modified" header system... im really not going to post that as it's just crap sheet metal from an old house stereo system lol but had those nice little vents for cooling which will allow the intake heat better....


See that orange cable --- that's going to my 13 ponies electric assist... does not sound like much but in first gear the car could pull a stump out of the ground at just 1,000 RPM idle speed lol

[A.K. Boomer]

. My butterflies are screwed onto the shafts like your Honda. I suppose they have the same flow restrictions. But I don’t seem to be notice!

Sid

That's probably because your lower in altitude and with that engine you have you could basically suck a potato through the intake system -- plate and all, maybe even throw in a dicer to get full length fries lol

[JRouche]

JR, Is your Lexus direct injection gas? if so that's why the two injectors in the top, it's a "hybrid" injector system designed to keep the backside of the intake valves clean, one of the problems with going direct injection gas is that you no longer have fuel washing over certain parts to keep them clean yet with valve overlap and certain RPM ranges creating slight backflush you can get combustion carbon build up,

Yes Sir, you are correct. I had know idea they were doing that on toyota engines. The high pressure side is a beast, think diesel engine injectors. High pressure and high cost.

My engine only had 5000 miles on it. But I had to do it cause it was out of warranty (bastards) and I cant afford their tech time.

So I popped the entire lid off just above the heads and learned some things. Went through a roll of masking tape and a sharpie identifying every connection.

You could probably just look at it and know what it looks like under 50lbs of wire. Thats why I like my chevy 355, easy and fun.. JR

[A.K. Boomer]

JR that thing sounds like a complex beast, when I see tons of complexities before a tear down I break out the camera,,, then challenge myself at not using it unless I get stumped, always nice to have detailed pics of all the hose and wire routing and countless other things,,,

Did you miss a zero in the miles your engine had on it before you had to go into it???

[JRouche]

JR that thing sounds like a complex beast, when I see tons of complexities before a tear down I break out the camera,,, then challenge myself at not using it unless I get stumped, always nice to have detailed pics of all the hose and wire routing and countless other things,,,

Did you miss a zero in the miles your engine had on it before you had to go into it???

Yes indeed, took many pictures. I posted them here not too long ago.

I was mostly afraid to jack up the wiring. So I taped each disconnect with blue painters tape lol. High level engine work I do around here.

Yeah, I said 5000 miles, it was actually 4850 miles. And at three years they told me to shove it. Three year warant? How come I didnt see that coming for a five year loan? I missed the ball one that because I was used to other companies going automatic with 5 years at least. I was side lined with Toyota.

The problem for them is when I did some investigative work on the engine. It is a complicated engine. I think I could tear the whole thing down to bearings and then back without a book.. JR

[A.K. Boomer]

Yes indeed, took many pictures. I posted them here not too long ago.

I was mostly afraid to jack up the wiring. So I taped each disconnect with blue painters tape lol. High level engine work I do around here.

Yeah, I said 5000 miles, it was actually 4850 miles. And at three years they told me to shove it. Three year warant? How come I didnt see that coming for a five year loan? I missed the ball one that because I was used to other companies going automatic with 5 years at least. I was side lined with Toyota.

The problem for them is when I did some investigative work on the engine. It is a complicated engine. I think I could tear the whole thing down to bearings and then back without a book.. JR

Geeze you barely drove it,,, what went south on it before it's first scheduled oil change???

[CarlByrns]

How does directing warm air to the intake increase output?

[A.K. Boomer]

Carl --- I believe it has to do with metering out fuel for proper atomizing conditions and cold air does not have very good qualities for that, there is an ambient air temp sensor inside the intake plenum to keep track of this,

I know there is the argument that cold air is more dense - contains more oxygen so although even though the mix has to be enriched you end up using less throttle plate and overall approximately the "same" as you would with it being warm and leaner mix and more plate, but, there's another factor and that's not that it's just leaner to compensate for the thinner air - it's leaner yet again due to having much better atomizing...

what i can tell you is this car takes a major hit in MPG ratings from summer to winter, and it's not just winter gas - and not thicker fluids (even though the trans just uses 10W30 motoir oil and the engine uses 0 w 20) - it's mixture control due to incoming air... I still have the same gas in the tank that I had a month ago and just because we have warmer days now my rating went from 55 to 65 mixed driving conditions... Whats your take on it? It's looking like I won't get to verify what im doing till next year cuz the weathers turned so damn nice lol

I will add this - im compensating some for the fact that I know the cars in "enrichment mode" longer in the winter months --- in fact long trips with the engine fully warmed and all fluids warm the real time mileage still takes a major hit just going down the highway..