I have all motor b20vtec just put in my car using 440 injectors hondata s300 p28 base map 70mm throttle body. Everything in the motor all new the car starts idle ok but when i test drove it it won't let me go past 3grand but when at idle and not driving I can rev it past 3grand everything seems to work fine can anyone help me out so I can fix this...and when I drove it my rpm gauge works but not my mph.

 

get a tune. the basemap you're using is garbage, and is nothing but a basemap.
stop driving the car immediately, you WILL blow up your motor if you keep driving it on that map. Get a tune. by a tuner. in your actual car. nothing over the interwebz, nothing through email, nothing handed to you on a flashdrive. get an actual full tune. a street tune, or a dyno tune, or preferably both, and preferably on the same day, and touch up on a different day when the weather is different so the compensations can be more accurately set.

 

Why a P28 base?? At least try something close to you actual motor size/combo. You do need a tune but I understand not having the funds or a tuner close to you...

Start with a P30 or P72 base and put a wideband in it ASAP.

 

I had this happen when I had a vtec, I can rev high just idling but when driving it wouldn't want to go past 3k rpm and my mph gauge didnt work. I replaced the speed sensor and fixed everything. I believe the speed sensor has to work in order for u to drive in higher rpm so u can engauge in vtec. But that was my problem mayb replace vss ( vehicle speed sensor )

 

p28 base sometimes doesn't work properly. use a p30 base.
p72 base can only be used in p72 ecu's.

for those not familiar with the terminology I'm using, when I say "base" I am referring to the format of the mapping used to create the basemap/tune. IE when tuning an LS, the car already comes with a pr4 ecu, so you would just chip that for say crome. then when creating a map for it, you start by loading the p30 base, which is just the raw stock map for a p30 ecu. you then change everything in the map to suit the setup it will be used for, like disabling vtec because p30 is vtec and LS is non-vtec. then tune all the compensations and fuel and ignition maps from there.

a bad vss will make vtec not work, but it should not cause it to not rev past 3k. the entire issue with the op's car is the map he has loaded to the ecu, it is far from correct for his setup, and will quickly cause damage to his engine.

 

The base map I have has everything from stating the injectors I'm using and when buying it I had to tell them my set up I'm running so they do a base close to my set up but I do have to get it tuned and p28 I have a 92 Integra obd1 I know I had a problem my injectors wouldn't fire something with the harness but when fixed it cranked up fine .just now when driving I can tell the car wants to go but wont pass 3grand something holding it back.

 

you need a tune. seriously, stop driving the car until you get it tuned.
a basemap is NOT a tune, and is ONLY suitable for starting the car to check for leaks, and sometimes to drive it to the tuner to get a TUNE.

but on a side note, do you have a CEL? any trouble codes stored? tuner's don't like cars showing up for a tune if the car has issues that need to be fixed. fix any problem the car has before getting it tuned if possible. if you can't fix it, let the tuner know and ask who the tuner recommends fixes it, including the tuner themself. then get it tuned.

 

After that test drive I haven't driven the car .
Motoxxxman you know of any good tuner in mass?

 

where in MA? it's a big state lol

I'm in central CT, and willing to travel a bit. the dyno I use when dyno tuning is in northern CT, at ECS Performance in Windsor.

 

Motoxxxman look at this video my car does the same thing If u can't see it look up Honda accord type r 3000rpm problem.
Mass right in Boston

 

ah, boston is a bit far from me. I don't know any reputable tuners in that area. you can try the tuning section here on the site. or go on hondata's website for a list of registered dealers/tuners.

in that vid it's hitting a rev limit, because he has a cel. you can see the cel lit up in the whole vid. do you have a cel? if you do, what is the code, or codes?

 

Can the vtec oil pressure switch give that problem? I can't member if I have a cel I havent driving the car or had time to work on it I been looking around to see wat could the problem be but I'll check and see

 

not usually no. when the oil pressure switch has a fault (or is missing), it'll throw a cel and set a code, and will disable vtec. but it often wont set a lower rev limit.
besides, if you don't have a vtec oil pressure switch, it should be disabled in the map, which eliminates the possibility of throwing a code or anything else. the ecu wouldn't even know to look for it.