i have d15b1 on a 91 civic hatchback, which im in the process of replacing the head gasket. since i have it torn apart i was thinking of making some upgrades. my goal here is not power, but mpg. So, i was thinking of replacing the following parts:

cam gear - (unorthodox)
crank pulley + alternator pulley (unorthodox)
pistons (????)
rods (????)
bearings (acl)
intake manifold heat shield gasket (???????)
flywheel - (fidanza)
headers - (dc sports) - will this fit with a/c ??

i could not find forged pistons (stock bore and compression), forged rods, and intake heat shield gasket for d15b1. Are they the same for d16a6? Where can i source the parts im missing?

i know fiberglass body parts and light weight wheels also increase mpg, but i'm only working on the motor for now.

 

Forget all those motor mods, get an HF tranny. That will save alot more gas.

 

tell me this, how are any of the parts you listed gonna help fuel economy??? a headER, not plural, can by improving air flow, but personally I think a good tune up and a good sea foam cleaning would yield better results than a cam gear or rods. (cam gear and rods, WTF???)

 

heres a intake heatr shielding gasket for a d15b1
http://bisimoto.net/store/index.php?...roducts_id=126

 

aerodynamics will be your best mod after a regular tune up.

 

***maybe*** lightweight pulleys and flywheel **might** help a little, but aero improvements, weight reduction, HF transmission, and most of all driving habits will yield the most results. Low rolling resistance tires, and tire inflation can have significant effects on mpg, but it can be difficult finding reliable information on rolling resistance... and the practice over-inflation always sparks a debate over safety..

 

thanks for the info. I figured by reducing the rotating assembly weight and exhaust backpressure, the engine would take less fuel.

 

what is sea form cleaning ?

 

Not sea form it is sea foam,it is an engine cleaner/restorer that you can get at any parts store.

 

oh lol , so does it really work

 

yes it works, but, it doesn't improve so to say gas mileage, but will help restore it to factory gas mileage. after years of driving you get carbon buildup in your head, which will decrease mileage. adding sea foam through a vacuum line (i use the brake booster line) to get the sea foam directly into the cylinder chambers will clean the inside of your engine very well.

here is a link to a post I did describing the methods for using sea foam. it's the 3rd post from the bottom.

Sea Foam uses

 

thanks

 

I can personally vouch for the seafoam cleaning. Been doing it as regular yearly maintenance on my 02 subaru and my 91 CRX keep its running like the day i got em'

 

Put it back together, sea foam it and swap in a hf tranny maybe a lightened flywheel and leave it, for the $ you are talking about spending you could buy way more gas then you would save becoming more "efficient"

 

oh god. seafoam is a load of crap.. if you want a clean engine, get it hot tanked. my old roomate heard from someone that it was a great idea, and he did it on his Eclipse GSX and his CRX, and both of those engines will never be the same again. The amount of crap that stuff gets in your oil is ridiculous. The bottle says you are supposed to run your car while introducing it into the vacuum system, so its going to be in your oil WHILE YOU CAR IS RUNNING. All that ****. In your oil. Bad idea. Your piston rings will not seal properly afterward until you replace them. I am sure there are plenty of people who disagree, but I have my old room mate's D16A6 with a hole in the block to prove I am not just nut swinging..

here is a pic from the bottom of that block..



and one of the pistons:


DONT SEAFOAM!!

there are a lot of people on here who will vouch for seafoam, but in a lot of cases it makes your life worse. my roomate for example. he seafoamed his a6 after I warned him that maybe he shouldn't. All that stuff that breaks up using seafoam, well it has to go somewhere. and to your oil is where it will go. you can change your oil to help clean everything out, but the only right way to clean an engine is to hot tank it.

cliffs notes: all I know is that stuff will never go into any engine that I own. If it was "good for your engine" it would already be in your oil. Here is the whole gallery of pictures just in case you need more proof http://mycomputerninja.com/~jon/blownd16/

 

well i did the seafoam today and i gotta say it did pretty good but i only put it in the pcv hose

 

Sea Foam in the oil????

I use Sea Foam all the time and it works great but I run it through the motor. I put it in the gas tank or in the throttle body while the motor is running. NEVER in the oil.

 

not in the oil

 

What if you were to use it on an engine with 330000+ miles? I am afraid the gunk is what keeps it running.

 

Hate to burst your bubble, but the pictures above are from seafoaming the engine through the pcv..

To be perfectly clear, I have an n=2 sample of cars that were seafoamed, both not by me. One of those cars survived the process, a 1g awd turbo eclipse, but the 91 crx si results are pictured above. Both cars went through the process and had oil changes shortly after the process. The crx blew up maybe a day or 2 after seafoaming. The eclipse is still running, to the best of my knowledge.

The crx was stock with the exception of a CAI.

All I can do is present the evidence. You guys get to be the jury.

 

If you pour it in your gas tank or suck it in through a vacuum line or intake all it will do is clean the injectors and the carbon in the combustion chamber. I don't know how you are using it but from the damage you are showing, it looks like it got in the oil and thinned it out so much that it spun a bearing and broke the rod.

 

scary.

 

If you really want to get the gunk out of the engine just drain the oil and drop the pan, then wipe the crap up. Put it all back together with a new pan gasket that we all know was leaking anyway.