Nextelbuddy

im going to go ahead and get the edlebrock manifold this weekend and was curious about one thing. im going to be using hondata with my chipped p72 ecu. now i know that the p72 ecu opens the secondary butterflies on the stock manifold but what about when you have a manifold with no secondaries? are there any performance drawbacks to this? should i go ahead and just use a chipped p28 for hondata since i will be using the edlebrock single stage manifold with no secondaries?

HXMan

You can sell the P72, buy a P28, and make a profit.

OBD1 P72s usually go for over $250.

P28 less then or equal to $150.

Nextelbuddy

yea i figured that but what will happen if i use the p72 with the new manifold? will it hurt anything?

InfamousGSR

I would like to know also. Also are there any disadvantages using the p28 ecu on a B18C1? Is the rev limiter all the same and does it automatically retard timing etc like the P72?

Nextelbuddy

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nextelbuddy &raquo;</TD></TR><TR><TD CLASS="quote">im going to go ahead and get the edlebrock manifold this weekend and was curious about one thing. im going to be using hondata with my chipped p72 ecu. now i know that the p72 ecu opens the secondary butterflies on the stock manifold but what about when you have a manifold with no secondaries? are there any performance drawbacks to this? should i go ahead and just use a chipped p28 for hondata since i will be using the edlebrock single stage manifold with no secondaries?</TD></TR></TABLE>

anyone else have any ideas?

ski_rebel_3

From what I have seen, the P72 works fine with the Skunk2 IM so I don't see any reason why it wouldn't be ok for the Edlebrock too. Unless I am mistaken, when the RPM's get over 5800 the ecu sends a signal to open the secondary butterflies. If there are no butterflies present then it would still send the signal but nothing would happen.

I have some notes from when I reseached this a while back. I can't remember where I got this or who originally told me all this but this is what I wrote down. If I am wrong someone please feel free to correct me. ( Since I don’t want to plagiarize or take credit for someone else’s work, if anyone reads this and remembers telling me this then by all means please take credit!!!)

Anyway I belive on a stock GSR there is a relationship between cam lobes and the intake manifold runners. In theory it would look something like this:

Stage 1 (0-4400 RPM): Low-lift cam lobe and long intake runners.

Stage 2 (4400-5800 RPM): High-lift cam lobe and long intake runners.

Stage 3 (5800+ RPM): High-lift cam lobe and short intake runners.

The only possible thing I could see happening is that the relationship between the GSR cam lobes and the short or long IM runner stages on the stock GSR IM would change and look more like a type R's that uses a single stage IM.

Kinda long but I hope that helps!

Flamenco-T

Jim is correct,

the ECU will send a signal to the IAB activator to open the secondary butterfy, but it will not send anything back to the ECU, it is a one way command therefore, it will still sends the signal, but since the JG does not have the secondary, then nothing will happen.

You can set the VTEC anywhere you want to on the ROm Editor

stan

Nextelbuddy

great then that means that i can use my p72 wit hondata and the edlebrock intake manifold with no performance problems what so ever?

TeStUdO

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nextelbuddy &raquo;</TD></TR><TR><TD CLASS="quote">great then that means that i can use my p72 wit hondata and the edlebrock intake manifold with no performance problems what so ever?</TD></TR></TABLE>

Yes, ive ran a P72 with my Skunk2 for a long time with no problems. Before that I never even had my butterflies hooked up to the IAB. Runs with no Cel's or problems.