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hey

i have an r32 with rb20det in it

its got about 140,00kms on it

the problem is there is a big flat spot between 4000 and 5000 rpm

its a real pain cos its right in the useful part of the revs

the car has jjr coilpacks

bkr6e-11 plugs gapped down (not sure by how much tho)

rb25 turbo

front mount

cat back zorst

apexi pod

bosh 040

and a turbosmart bov

it has a full service (inc new plugs) and changed nothing

chenged ecu and it got a bit worse

the flat spot was originally 4000+ but after finding the cas bracket snapped in 2 i fixed it and i regained power form 5500+

i then cleaned the coilpack connections and it got a tiny bit better

i advanced the timing a tiny bit and i now have power from 5000+ but still nothing in between

car is running 12-14 psi (no boost controller and get some boost creep in 3rd or 4th or 5th up to .9 bar)

when it hits the flat spot its fully spooled and sounds ready to go

i've searched the net and may look at the knock sensors next

If you have an idea of something to check post it up and i will try it

Thanks

Tom

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I had this same problem.....

All i did was gap my plugs back to standard 1.1mm.....

Some say running 0.8 is good for helping with boost increases....but thing is, running low gap wont burn all your fuel...

Try running 1.1mm on your plugs....even try some copper pluggs at 1.1mm

Might also pay you to check out the heat range on your plugs... - Actually...6's are fine for your setup..leave them be...

Also, chuck a boost controller on...even a $90 turbosmart manual one will do...you need to run around 11-12 PSI....14 is a little silly on your stock turbo...plus you'll have ecu issues on your stock computer...

Cheers.

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plugs were heat range 6 1.1mm gapped but i dropped the gap down to see if it would go away

filter is a month or two old (prev one may have been put on at factory :-O!)

not sure on the age of the bosch but 2 years old max

gonna run some more injector cleaner through it in a high doseage and hope for the best too

anyone recommend a good one?

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