THE COLT v. 2

[coltboostin]

After being asked 497120342134 times to build another, I was happy to save a clean local chassis that was one foot in the grave.

[/IMG]

I am going to toss it together with parts I have laying around collecting dust. I should have all of no money into the thing after its all said an done-I am confident I have enough junk laying around to put it together.

Next to its TDB brother-an 85 RX-7 picked up a few weeks earlier. That will be the long term-winter deal.



This wont be the Busa slayer the old Colt was (for now) but should provide fun for the rest of the season. Making the shootout is a maybe- but with no time between the work, a weekend trip to "The AC" coming up, and not having a motor together, it may not be likely. We will see! Stay tuned to see what parts I dig up for her.

Found enough spare parts to toss a motor together! She"should" hold. Crank looked good. rods and Pistons looked good. Did not have my Mic. or Calipers at the house, so it had to pass the EYEBALL test. Poured some Beer on it just in case....

Now, I am a little sketched out about the bearings-never used this brand before, and I am not sure I would use them again. The seem to have a smaller tab to prevent the bearing from spinning that was what in there (presuming Federal-Mogul as thats what I usually use) but its all I had on shelf-and I am pressed for time!

 

[Pipnorcali]

What's he doing with the rx7?

 

[GSR-VR]

This is going to be a sweet colt! <3

 

[arrowhead]

What engine 61 or 63?

 

[dikdiamond]

What's he doing with the rx7?

If I recall Coltboostin stuffed a 4G63 in an RX-7 years ago.

 

[coltboostin]

Again big thanks to Detective coating for the great work and the very fast turn around. Everything was packaged very well. No one should have a hesitation sending him anything just because he is not local! Best work I have seen in a while.

I will admit the green in pictures was scary-but in person it is SICK. Iridescent almost with a "white pearl" effect. I love it!

Small update. tried to do some IM testing and it turned out to be just a LONG night. Reason? The stock Colt Clutch Master gets int he way of EVERYTHING-I forgot how much room putting it IN the car gave me!

Took forever to swap, found a leaky injector seal that had to be fixed and then the car retested-when it was all said and done I only made test pulls @ 19psi, and 24psi. It was such a pain in my ass I doubt I will ever do any more testing like this.

JP&#39;s 4G63 Colt at the Dyno - YouTube

I did make some good observations though.

Stock Vs Venom, both on stock TBs

1)The Kelfods are a MUCH better top end Cam than the Comp101200s. No back to back, but looking at old dynos of cars I have tuned, the power band was still climbing at 8k, with BOTH manifolds!

2) The stock IM kicks ass below 6500. At any boost level, the car did not make more power until after 6400. Also, at 19psi power did not fall off at 8k with the stock IM-the Kelfords are keeping the band nice and flat. Would this be different with 40psi? Maybe, but I doubt it. Would this be better with a differing IM? Maybe-but at this point I TRULY feel that if you do not go north of 8000rpm or north of 500whp, the stock IM, IMO, is the bets manifold for the job. Any turbo, any power level.

3) at 19psi, BOTH manifolds were within 5hp- stock at 445, Venom at 450-but the Venom had a much later peak and the stock IM had better power under the curve. At 24 Psi the stock IM Saw 484whp and the Venom made 507. This was with no additional tuning-11.0 AFRs on a pump/E85 mix. As the boost goes up, the Venom starts shining. I would attribute this to the plenum volume, and shorter runners which lend themselves for high RPM airflow.

On the street-the loss of low end torque is evident with the SMIM. Some I am sure could be gained back with tuning, but it is a totally different car-much, much less"torquey" off boost.

Conclusion-

The stock IM really did impress me, and I truly feel any car with power goals around 500whp, or a redline south of 8k really may be better off with it. The car had more "fun" factor on the street with the stock IM, and the powerband showed it. The Kelfods carried the power great to 8k even with the stock IM at mild boost. With a higher redline though, and loft power goals, a SMIC should still be on your list of needed parts-but I feel a good cam should be first on the list.


Big thanks to Eric@ Backstreet performance for allowing us to use the dyno!