I have a dip in my power band and can not figure out what causes it..

skunk2 intake mani with whale *****
itr block
itr pistons 81.5mm
gsr head, stock ports
skunk 2 pro 2 cams
hytec replica header
rc 370cc
2.5 in str8 pipe to muffler not sure name brand of muffler
made 194whp 136 ftlbs any input will help thanks

 

vtec engagement point? check air/fuel and ignition

 

Its not the first time I've seen a dip on a graph using the pro2's. Let me see if I can find another graph as comparisson.

 

k thanks what do you think it is??

 

That is the header. 100% sure.

The primaries are incorrectly paired for the size of the merge collector used for the 4-2 transition. The secondary length is not long enough for the secondary piping diameter used. A couple other things that make these manifolds junk.

If you want a smooth powerband, pay for a R&D'd header.

From searching for 5 minutes in the all-motor dyno thread:

ITR cams with:
Red - Hytech Replica
Green - DC JDM 4-1


Skunk2 Stg1's
Hytech Replica Header


Buddy Club 3+ cams
Hytech Replica Header


CTR cams
Hytech Replica Header

 

I also noticed that from looking thru a few dyno graphs...

You beat me to it.

 

Here's mine... I used the same hytech replica header...

 

probly the cams too big for stock compression my boy put down 200whp on a stock itr bottom end springs/retainers an skunk2 stage 2 cams not pro's

 

lol...interesting! thats what i have as well. how does the real hytech perform?

 

yes I would like to know as well if this happen to the real Hytech. I was going to purchase a fake Hytech

 

No, because John makes each header to match your engine. There are no "off the shelf" manifolds produced by John.

 

Are you sure about that? What about the Hytech production header which is sold by Larry and of which these replica headers were copied?

 

BTW, same junk header here with the same dip in powerband

 

I guess I should say that he no longer has an off-the-shelf header.

All the HyTech Replicas floating around were originally spec'd by John a while ago to be built by a Chinese firm to be used as a Production unit. Then that firm, whom anyone can buy from, became more well known, hence the steep rise in "Tri-Y/Hytech" replicas floating around on ebay/honda-tech/am-pm...

PS - Put that header on a 13:1 2.1L B-series with 11.5-12.5" intake runners and there won't be a dip anymore...

 

my friend made more power with the skunk2 stage 2 than the pro2 . dyno guy said that cams where to big for the 1.8 and something about the compression
pro 2 made 198
stage 2 made 206

 

I really appreciate all the helpful words

ok so a new header will be in the works.. what other brands do you recommend?

are there any other tips as far as bolt ons go for with this set up?

 

I would recommend trying to make a run open header to see if it helps with the power dip you are seeing. I have a feeling there is a ve restriction.

Another thing you may want to try is pro1 or stg2 cams instead.

 

so you think the car is over cammed?

 

For stock compression, I definitely think the motor is over-cammed. Check Skunk2's website for more details.

 

the car is in the mid 11 compression ratio

gsr head on itr block, milled with itr pistons will yield stock compression??

 

Cams are fine. That dip in the power is the Replica Header. /Thread

VTEC lobes are not much different than the Tuner Stage 2's.

What is your cam timing?

 

when it was tuned i believe the exhaust was - 3 degrees and intake + 1 degrees
this was done also to get the car to idle cuz two other tuners could not figure why it would not idle

 

any one else with any ideaS

 

Your cam timing is way off.

You should be around 0 to +2 on the intake and +3 to +5 on the exhaust.

Did you read the installation specificaitons that Skunk2 provides? Look at the install centerlines one more time...

 

lol, you wanna guess my header too?