I'm curious about the Motec setup.

Did you get the plug-and-play harness from JRR? Or from Boomslang?

 

I did get the PNP and M1 package from John Reed Racing. He's a wizard.

 

Clutch/trans are broken in with over 2000 miles on them now. Many pump gas tanks and low boost/sadness.

Car is running well on ethanol now. Swapped in new spark plugs gapped at .018. Put it on the dyno the other day and it made 600whp on E78.

The 4.31 final drive makes the car feel quicker but now it will spin in 2nd with less power then 4.11 final drive. If I move to a better tire then I should be able to turn it back up and not spin. I'm not totally sure what FD I like at this point,but I'm leaning towards the 4.11.

 

Ever thought of moving on to clutch pack front diff to help putting the power down?

 

His car has the OEM torsen front diff. It not going to see a huge improvement going aftermarket other than in the strength department.

 

I need a better tire, or just run moderate power in the low gears .

Hoping my OEM Diff goes the distance for what I do with this car.

 

Hi Tim,

How do you like boost-a-pump over a dual pumper? Is it more reliable? Can the sensor fail where fuel oump doesn't get the extra voltage? Is there a way to test and watch to make sure it's working properly? Is there a fail safe to set aftermarket ECU to cut boost if it fails?
Thanks!

 

Hello Don, Since I'm on a small turbo and like to keep things simple I'm sticking with one fuel pump. Occasionally a twin or triple pump setup can have a pump go away. The Boost a pump has been around for decades and has an extremely low failure rate. This particular boost a pump is off my 1998 Cobra from 2003-04 . Its treated me well. It set to come on at 5psi and supplies 16Volts to the 450 / 274 pump I have.

Any aftermarket Ecu has a failsafe to cut with whatever parameter you set. Most set the AFR to cut around 12.0-12.2AFR when wide open on a boosted car. You could also cut based on fuel pressure, oil pressure,boost,wheelspin etc..

A single 450 / 274 pump will make over 700whp on a Dynojet (E85) with large injectors at 14V on an Evo. The new 450 /525 pump will make even more. Either pump will flow more with a boost a pump @ 16-17Volts.

http://kennebell.net/products/accessories/boost-a-pump/

 

So after running some borrowed RE71R's at the autocross a few weeks ago I wanted to compare them to my Continental extreme contact tires. I bought the Conti's years ago since it was a lightweight tire and handled well in the wet Florida summers. I had also gone from the stock 4.53 final drive to the 4.11 final drive and wanted the lightest 25" tire possible to try and regain some of the acceleration I lost. I like to keep rotational weight down so its easier on the driveline. Now, These are two different sets of wheels so assuming the wheel weight is the same the new RE71R weighs 5-6lbs more then a nearly spent Continental. Same 255-40-17 25" tire The RE71R's are a MUCH better tire for auto x and high speed stuff. Stiffer sidewall and a heavier duty tire for street/track use. They do pickup everything and sandblast the cars paint going down the road. The Conti's hooked really well with the 4.11 gearing but now struggle with the 4.31 gearing in first and second . The steering isn't as sharp with them but they still work well on the street and will slide on request . The ride quality seems slightly better with the Conti's with the softer sidewall.

 

The contis made very good wet tires but they won't be able to tango with 71r's in the dry. Pretty normal results. How you like the 4.31?

 

I picked up a set of those Contis a few years ago for some cheaper street rubber vs killing better stuff. In the rain they are fantastic and honestly on the street its a solid tire. I did however do one auto-x on them as the night before swapping on my other wheels I found a bubble on the sidewall so opted to just have some fun with the Contis.

If you are used to the levels of grip with an extreme performance summer tire then the Contis will be frustrating as the grip just isn't there relatively speaking and the sidewall isnt nearly as sharp. That being said I had probably one of my most massive drifts during an autox on these tires. So yeah it was entertaining, just not fast.

 

100% agree.
It spins alot more with the 4.31's

I will need to run it at the drag strip at some point , if it doesn't pick up 4-5 mph in the 1/8th or 1/4 then I'm for sure going back to the 4.11.



Running the Conti's and 4.11 gear I was able to power slide in a more controlled fashion at that traction level. It was also nice to not shift every two seconds around town. Years back around 580ish I went to the drag strip and left at 5-10psi without any drama and went 10.8@132. I also ran it a bit harder on a roll style drag race and went 136mph.

I was also able to put down more power with the tall 4.11 final drive with the Conti's. I could floor it with 30-32psi in first and it would hike the tire a bit but move out hard. 2nd gear would take 34-35 psi. Now if I was going to compete then the 4.31 and a sticky tire would be much quicker around the road course or drag strip.

 

That was an awesome drift / save! Tires... not so awesome

 

Awesome thread, thanks for taking the time to share everything. I'll have to do that with my build, information is beneficial to everyone. Ever make it to the drag strip? Also are you still on the s2 cams? For some reason I thought I saw a youtube video with this car on R2 cams(or maybe a swap was mentioned in the comments, don't remember). Good ****!

 

Thank you Sir.

I didn't build the car for drag but have been a few times. The "fun per dollar" isn't there for me. I used an ACT 6 puck and it would slip over 15-20psi on the launch so I would leave at 10psi or so. I went around 580whp-600whp with the tall 4.11 final drive and street tires . It went 10.8@132 crossing at 7200-7400 rpm. I've also done a roll race style 1/4 run and starting in 2nd with a little more power it went 136mph out the top.

I'm using S2 cams. Easier on the valvetrain, less of a lopey idle and still produce great results IMO.