Safe Rev Limit with barely built car

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khai_tuan_nguyen

Senior Member
Hello I swapped a B20b with a B16 head. The block has been machined and i am using Arias pistons. I have a 97 GSR ecu and wanted to know when should vtec kick in and what is a safe rev limit.
 
With the P72 ECU VTEC is at 4400 RPM, and the fuel cut is 8200 RPM. You should be safe to rev that high.
 
4400 rpm vtec should kick in? I don't feel it at all in 1st or second gear. Any ideas? The only thing i can think of is the vtec solenoid is not wired up right. I have full oil, the engine is still being broken in. Everything else runs fine. I have trouble having it start when i have not drove it in a few hours.
 
8k would be the max taht i would push the oem b20 bottom, plus with your b16 cams you aren't making power past that point anyways. I do suggest getting a tranny with good gearing such as the ITR/GSR/SiR, try to get one from a 1.8 since the differential is physically larger.



Milan
 
if you havent upgraded the head at all i wouldnt rev past 8k either. i would get a different ecu also, vtec kicks in so low because the gsr has secondaries (which open later) i would suggest getting an ecu for the b16 or type r, which will have vtec engagement at a better rpm.
 
JDMilan has an excellent point about the oem B20 block - 8k rev.
Remember B20s were not designed to rev at high rpms so unless you are running
a block girdle and oil squirters, continuous HIGH rpms = detination!
 
WOW thanks a lot guys for the help!!! I can not feel the Vtec at all at 4400. Any ideas? Also my main concern is reliability. Do you guys see any major problems with my almost stock setup. I want Honda reliability. What would be the next steps you guys would do for reliability (what first then second etc... i.e. cost is an issue, that's why its a priority list) Did anyone see my other posts about the weird problems i am having? I am getting a great response from this thread and none on the other. My other thread had to do with the starting and idling issue and a/c and power steering use. Thanks again guys and ifi can answer and questions or be of help lEt me know.
 
Originally posted by B18HyBriD@Jul 29 2003, 04:10 PM
JDMilan has an excellent point about the oem B20 block - 8k rev.
Remember B20s were not designed to rev at high rpms so unless you are running
a block girdle and oil squirters, continuous HIGH rpms = detination!

Uh... ok. :angry:
 
Originally posted by B18HyBriD@Jul 29 2003, 01:10 PM
JDMilan has an excellent point about the oem B20 block - 8k rev.
Remember B20s were not designed to rev at high rpms so unless you are running
a block girdle and oil squirters, continuous HIGH rpms = detination!

do you even know what detonation is?
detonation is when you have high compression with low octane, or the fuel/air mixture is igniting before the spark ignites it. it is not associated with block girdles or oil squirters or continuious high rpms.

a b20 vtec is as good as you build it, did you use ARP rod bolts? that should be your minimum. then upgraded rods would be your next move, other than that you would need to build the head (ie: springs, retainers, cams) for the high revving.
 
Read B16's post khai... I've seen B18's posts here today, and they're just full of magazine racer knowledge that I don't care to take the time and explain around. Not today. I'm tired.
 
Got you... thanks for the help everyone.... I will not be reving past 8k... What do you guys think about the vtec though. I have an extra si ecu, but i heard that the GSR is my best bet for non hondata or non chipped (i.e. fuel mixture etc. etc.) ... Any ideas on my other posts... the starting issue, the check engine light (code 6), or the clutch
 
Here are my problems.... BTW the car is still being broken in according to hondaswaps guidlines... lol. It is at 300 miles.


1) The car does not start all the time, it cranks over a lot and then finnally turns over and starts and sometimes idles low and dies. If i can keep the idel steady and let the car warm up then it idles around 1100 fine and then it drives perfectly, but then idles at around 1400. If i shut it off after it has warmed up and then turn it back on it turns over perfectly. IT only cranks a lot or dies when i have let it sit there for awhile.

2) I installed a brand new clutch (exedy) and the shift point is literally all the way at the bottom and sometimes i can not get it to engage at all. IS there a way to move the shift point. Any other ideas?

3) I am getting a check engine light code 6. I looked at what that was in the faq and it is the coolant level sensor or circuit. I replaced the sensor and still get the code. Do i have to reset the ecu or anything or drive awhile before it turns off?

4) vtec should kick in at 4400. I do not feel everything. I ran the vtec line to the ecu and have full oil. Any ideas.


Thanks
 
I don't mean to be make this topic stray, but B16.... "detonation" look up the meaning of the word.. In the racing scene we tend to associate it with low octane /w high c.r, pinging, etc.. the whole nine.

what I was getting at basically is HIGH rpms = detonation! Kaboom, blowup... whatever you want to call it it is not good for the motor.

after kaboom is rebuilt... Get my point. Thank you!

sorry if i came across rude to other members... I am a nice guy, really.
 
first reset yor ecu, and see if your throwing any other codes.

the stock gsr ecu should be okay for you, but you never said what compression ratio you are running. if you are running less than a stock comp. ratio that could be part of why your vtec isn't as powerfull as you want it to be.

your stock crank should be able to handle revs up to 9k just don't go that high cause your stock valvetrain can't and your cams wont make power up there either.

waht kind of oil pump are you using? i would recomend an ITR or upgraded b20.

check your throttle body and make sure its closing all the way when its just idling, if it isn't closing all the way that could cause your car to idle high.

check your hydraulic fluid in the brake resivoir and clutch resivoir, then bleed them both just to make sure there isn't any air in there.
 
Wow thanks for the help AGAIN!!! This site rocks. I have bled the clutch and it still engages at the bottom only. I am almost sure the compression is 12:1:1. I should feel it now correcT? Would an SI ecu be better than a GSR. AS for the check engine, i do not know how to reset the ecu, but when i changed the sensor i jumped the ecu to get the code and code 6 still came up. When you change the item that your check engine light says to how do you know if you actually solved the problem. Does the CEL go out automatically or do i have to drive it around. I am running a TYpe r oil pump. Any other ides to go off of? The throttle plate is weird. When i yank on the throttle cable and let go it idles lower than me reving on the gas and letting go. Sop i have a feeling it is the throttle plate, but i can not adjust it, because any looser and the accelerator diengages inside the car. Any ideas on the starting issues? Could it just be normal for it breaking in?
 
reset ecu - disconnect battery, turn lights on/off, leave for 10 mins, connect battery, start car and let it sit for 10 mins.

vtec issue - with the b16 cams and stock ecu you can't exactly FEEL the vtec engaging, it tries to be as smooth as possible. now if you get more agressive cams or fuel map you'd be able to feel it.

after you replace the item you'll need to reset your ecu for the CEL to go out.

as for your idle, try adjusting the screw on the top of the throttle body to higher the idle.

all the information you're looking for is in the faqs/references sections. (idle, ecu reset/codes, etc)
 
and for your starting problem:
you put your key in the ignition, turn it 2 clicks to where all the aux. power's on WITHOUT turning the starter. Count to 10, and then start the engine. This works for me most of the time and from I've seen a lot of other Honda drivers as well. I do not remember exactly what the problem was, probably fuel related or maybe electrical.
 
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