Well i bought a db8 shell with a db6 front end. I wasnt going to buy the engine but here i am posting. Its a boosted c1. Sure it sounds cool at first but then i learn more about it. Its a C1 with b16 pistons which would jack up the compression. I speak to the engine builder and he said he built it as a high compression engine. Didnt build it for boost. Well here is what i found. Compression on #2-4 210, #1 120. Leak down test revealed either a burnt piston or the rings are fried.

"now me and the mad scientist have to rip apart the block and replace the piston rings your fried"

Sorry couldnt help myself

Here are the "build specs"

b18c1
micro polished crank balanced and matched to rod lenths all new bearings (kings)
new oem gsr rods
new b16 pistons and new rings
block was line bored decked and honed
new head gasket
GSR head
ARP head studs
new dual valve springs
new titanium retainers
new valve seals
new cam seals
skunk2 adj cam gears
skunk2 throttle body i believe 72mm
skunk2 manifold
450cc injectors with resistor box
walboro 255 fuel pump
GSR tranny rebuilt all new bearings on it it use to grind 3 at high rpms now shifts perfect flawless
exceedy stage 1 clutch with stage 2 pressure plate
lightened fly wheel and was balanced before installed
both new axles
.58 ebay turbo boosted on 9psi with a street tune on crome (p28 ecu)
3inch down pipe to flex pipe and 2.5 full apexi exhaust car sounds mean and bov is LOUD (hks ssqv limited black edition) all motor work was done by Nate at Daily driven motor sports i can meet up at his shop he can show proof of work probably about 15k on rebuilt


Forgive me for my ignorance, im a chevy guy but as you can tell ill get into other stuff.

So it sounds to me like this motor has to be over 11:1. Sounds like a bad formula to boost. Im obviously rebuilding it. What do you guys think would be the best route. Take the turbo off and build an all motor deal? I love boost just like 95% of people out there. Any tips and advice is appreciated.

Thomas

 

Find a good tuner, and do a lot of reading. Boosting a 4 valve is not the same as boosting a 2v chevy. With a good tune and 93 octane I would not be worried till close to 12:1. The margin for error is very tight, so a good tuner and getting tuned on a dyno is a must. From the calcs I found your probably at a minimum of 11.3:1. I defiantly cringe at the ebay turbo they really scare me all the horror stories I have read, I would rather go NA than use it.

 

What is this 1999? 11:1 isn't high compression for forced induction applications. It is considered moderate these days. Most would wouldn't consider high compression until 12 - 12.5:1 with today's advances in fuel and tuning capabilities. There are setups running closer to 14:1 with pump E85 and pushing over 20 lbs on a 60 lbs per min turbo. You have a lot of research to do haha.

A lot of people on here dabble in more than just Hondas. I hate to break it to you but 11:1 isn't that high even or boosted Chevy's. Things like aluminum heads and E85 have changed that misnomer a long time ago haha. Most supercharged setups are at minimum 10:1 anymore. Hell my Windjammer Suburban is 10:1 with iron Vortec heads...

 

Hi, welcome to the site. Before you decide to rebuild everything are you sure the low compression isn't valve related?

 

@met thanks for the useful information. Makes me feel a whole lot better about jumping into this. We have 91 or 92 here octane up here. Yea the ebay turbo is done for, if i do anything it will definitely be getting a quality turbo.

@onebadturbocrv I admited my lack of knowledge on the subject. How much of what you said was actually constructive bro? Pretty much just repeated what the first dude said. Why do i think like this you ask? maybe because for the most part all i have built was iron block iron head v8s... OR maybe its because i hang around old timers when i pit on late models...? Ive been taught by old timers so sorry about my ignorance. One of our motors is pushing 15:1 and the other is 17:1(have piston issues though). I'm no stranger to performance this is just a new relm.

@muckman yea bro i compression tested it, got 120. Then leak down tested it and it came full bore out of the oil dip stick tube. Put a bit of oil in the cylinder and it sealed up better but leaked out eventually which is making me think more torwards rings.

So all i want is a fun street machine. I dont need to burn the tires at 60mph. I think 300hp would be a fine mark. I'll look for a good tuner, i think ive heard some good things about people around here. Anything anyone would do that would be a good idea while i have it apart?

Thomas

 

If all your wanting is 300 nippon makes a cast piston that for the most part is a pr4 piston with thicker ringlands. You can get em on ebay for $180 or $220 if you want to use aftermarket rods. That would put you in the area of 9.6:1 iirc.

 

I more than expanded on what he said. I guess you don't understand dynamic compression though because the ratios are higher than what you posted for a N/A engine...

If they are stock pistons there is a very high possibility it cracked a ringland from detonation.

N/A is a very expensive way to go slow in the Honda world. You spend almost as much and more in some cases than comparable V8 parts when you can just put a turbo on it and call it a day. For 300whp a completely stock VTEC engine with a GT28XX turbo will put you where you want to be. It will have a lot of midrange which is what makes these fun. At that power level with a good tune it will still be completely reliable.

Any upgrades you make while it is apart is just a waste of money for your goals. Repair what is broken and go from there. If you plan to bump up the power in the future just spend the money on forged rods and some 4032 forged pistons. This will give you the balance of reliability / strength and longevity. 2618 forgings will wear faster and require more PTW clearance.

 

@onebadturbocrv now bro this is what i wanted. Thanks for the info. The cheapest way is just to throw another b16 piston and rings and call it a day. Ill probably do a valve grind while im at it. 300whp and reliable sounds good to me. gt28xx are ball bearings right, leaving the t28 as a non bb. Looks like ill be searching for a gt28.

I dont plan to go crazy with it, not yet. Im currently building the bottom end of my 73 monte carlo 350. Stroking it with all forged eagle parts. Not cheap.

Thomas

 

Any trusted places to get a gt28?

 

Shodan

 

The market place is pretty good too.

 

The word of the day for High cr boost was pump E85 a reliable fuel pump that doesnt miss a beat, and if your really high cr with alot of boost the direct port injection keeps it happy as well. I was pretty boggled when I first learned the FRS came with 12.0.1 stock cr for a production mfg toyota/subaru but then learned there is two fuel pumps and two sets of injectors. So I investigated reliability of running higher compressions. Everything stated earlier just raises the threshold of ping the more you add the better. From what I have read E85 is the big one tho. and having this at disposal to you in your area is a big question, I dont have it soo shitty for me right. These are all questions for you but since, your goal is pretty low your questions become alot "simpler" lol

Only thing I would like to add is just go with OEM bearings. I know 1000hp B18 builds pro drag racers running them, why? idk . . . but they do!
I'm **** though, if they werent each individually absolutely perfect I would buy another set.