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CRX ECODiesel Ram
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Discussion Starter #1
Back on black friday Bad Guys ran a special on Rocket Motorsports cams and other parts. I couldn't afford the cylinder head...but I grabbed a Stage 4 cam (regrind). it took about a week for me to send my core in, and about 6 weeks before I got it back. They said they were busy as hell and I did not expect anything really fast (especially at the price!)

The cam was well packaged, and you could see the base circle was a LOT smaller. The cam lobe shapes had really aggressive opening ramp, and a lot more duration, I took a few rough measurements and figure about 1.5 to 2mm more lift compared to the Crane Stage 2 that was coming out, as well as about 15-20 degrees more usable duration.

The cam was finally installed yesterday, I also replaced the timing belt and drive belts and of course adjusted valves.

Start up was really bad, I had to pull a lot of fuel to get it to idle and ended up finally getting a nice idle at 1300 rpm. I topped off with fresh fuel and did about 5 miles of datalogging to adjust my fuel curves. I left base timing set at 16 degrees, and it was dead on with the timing light.

Even without optimized timing curves I am really impressed with the cam, low rpm loses a little bit under 3.5k rpm compared to the Crane, but power is still strong all the way to 8k rpm.

Overall i am really pleased with the initial outcome, and the communication with Bad Guys was good. The price was great, and hopefully the dyno tune I eventually want will really open it up. Definitely worth the $225 plus shipping to send the core in that it cost me.
 

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That was a great price, I saw when they had that deal going on and should have jumped on it. I just ordered a stage 4 regrind form my all motor z6 build. Paid A LOT more but have heard nothing but positive results.
 

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95 civic coupe
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I had the Stage 5 billet cam and made good power with flat torque. Now that i thought about it, I might be able to talk Rocket into doing a group buy for a cheaper cost if there's more people here that's interested. There would have to be at least 7 buyers to make it worth his time, or let me know who's interested and i will talk to him directly.
 

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1996 Civic Type DX
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depending on price, i would be in for a big all motor a6 cam.

stratton.
Only regrinds for the A6 and Y7 are available, so they're not really "big". Options are stage 3 and stage 4. VTEC stage 5 and up are new cams, not regrinds.
 

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del Sol si '94
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Im in as well. Need a cam for my itb A6 build.
 

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95 civic coupe
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I almost forgot about this thread and I will talk to Rocket now to get quotes for possible group buy regrinds.
 

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95 civic coupe
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Okay so here's what i got.

Normally rocket regrind is $385 and he can do $275 on the group buy of 6 or more and can be A6, Y7, Z6, Y8, DOHC ZC + shipping. The turn around time is about 1.5 to 2 weeks shipped back to you.
And lastly the bigger billet cams are $575 instead of $675 with the group buy.
 

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CRX ECODiesel Ram
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Discussion Starter #13
the a6 stage regrind is about as big as you can get on a regrind without hardwelding. I did not have much room left to adjsut valve lash.
stage 4 is 237/223 duration at 0.050" while the a6 is 193/195
lift is 10.8/11.3 mm compared to 9.3/9.1 mm
the ramp angle, especially on the opening side of the lobes, is pretty radically altered.

because of the lash adjusters you cannot really make the base circle any smaller and still be able to adjust, and to get more than that much lift from a new oem base circle will probably start getting making sure of clearance with the head casting. Since I am not likely to ever be porting the head, or going for forged internals to really spin my engine any higher I think this is as good as I am willing to go, and honestly it really is a lot of fun to drive....though since I have a new core Crane cam that has the OEM base circle AND more meat on it then stock it makes me wonder what could be done with regrinding that cam!
 

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Approximately how much fuel did you add with the new cam. any?

You said you took someout down low, which indicates a loss.
 

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Discussion Starter #15
The Rocket cam idles about 14-15 inches of vacuum. The Crane idles at 19-20 inches. So between 14 and 20 inches I took fuel out under 2500 rpm, in the first columns at low load I had to initially take out a little bit of fuel in a few spots.

Above 3k rpm and between 4 inches of vacuum and 0.8 inches I added from 7% to 11% with the largest increases above 6k rpm.

After contacting Rocket about initial cam sprocket adjustments he recommended +2 and I added +2 more for the milled head. That made some fueling changes needed in the lower rpm rpm range particularly. Looking at my before and after maps I see that after the cam timing was adjusted (and ignition timing reset) I had to increase fueling by 3-7% in my part throttle maps.

Using the SManager comparison tool there are 141 changes to the fuel map after street tuning the Stage 4 cam, 86 ignition timing changes. After all this it still is a bit rough starting and i have to feather the throttle when it scold for about 30 seconds before the iacv is able to keep it idling around 2k until it gets to its warm idle at 1300, but it cranks over a lot easier now. There are a few "weird" bumps on the maps that are not aesthetically pleasing but the engine seems happy with them so I am leaving it be until more datalogging says otherwise.
 

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Discussion Starter #16
Playing around with fuel flow calculations looking at my duty cycle, fuel pressure and injector size it appears that the cam increased peak power by 13hp. I can say the way it slams into the 8k rev limiter now i would tend to agree with that type of increase and the powerband being moved up.
 

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If you guys are serious about a group buy please let me know. I used to frequently lurk this forum but recently not so much. I am the largest distributor or RM products. Easiest way to get in contact with me is through PM.
Cheers,
Cole Mulvey Owner Operator Bad Guys Worldwide
 

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Discussion Starter #18
I am loving this cam more every day. Would probably be even happier if it was dyno tuned but as i data log driving it gets better and better.
 
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