80tq drag racing- Intercooler reevaluation [long]

[JShadzi at aol.com]

Jorgen, you are right, an interesting experiment-one consideration is that, from the beginning, I never intended to build a drag car, this car is built with every intention to drive tracks like Sears and Laguna Seca, so the IC is not as big of a consideration on tracks like that.  

Sitting in the staging lanes for 5 min at a time does not help, all the engine compartment heat coming up through the IC, a bad situation all around.  

Dragracing was a fun experiment, the car did well, and I learned a few things that need to be changed.  All in all, the fuel system worked flawlessly, what I was really testing all along.

My plan is to make the bigger IC and impliment water misters on the IC, a small fan may fit too.
Javad

In a message dated Wed, 29 Aug 2001  5:29:38 PM Eastern Daylight Time, Jorgen Karlsson <jorgen.m.karlsson at home.se> writes:

> Hi,
> 
> Hmm, 15.8 and 96mph is an very strange combination. As you say 96mph is more
> like a low 14', the funny thing is that you had an acceptable 60ft time. One
> run like that is very hard to explain and a whole bunch of them is a
> nightmare.
> 
> Since the 60ft say that your starts are good and the trap speed say that you
> make good power (around 200hp) I wonder what happened, the ET try to tell us
> 150hp. Somehow you lost at least one second between 60ft and 1320ft. That is
> very hard to explain but I have a theory.
> 
> The high ambient temperature and the intercooler sitting like it does
> probably give you an intercooler temp in excess of 120oF when you roll into
> stage. I remember that you use a Spearco core, these are very heavy and
> store a lot of energy. Very good on the street, less soo on the track and a
> disaster on the strip.
> 
> You can manage to make a good 60ft time without a good intercooler, or more
> like a interwarmer in this case. Then you probably spend half of the way to
> finnish with very retarded ignition (excessive air temp and minor
> detonation). The car is probably very slow now, you are hanging in your
> harness... The car then picks up its pace but since you are in a higher gear
> now you don't feel a lot of acceleration, anyway the car make a lot of power
> the last 200meters or soo. Probably around 250hp.
> 
> In any case you make a lot of power somewhere at the end of the strip, you
> can't loose time at the end of the strip. Time can only be lost at the
> begining of the strip.
> 
> I agree that an IC mister would have given you different results, I guess
> that you would have been sent back to the pits for inspection ;) All excess
> fluids must be collected and must not drip on the track... Freely translated
> from the swedish dragracing rule book. While not on the strip a mister is a
> very good idea. A fan would be a betterinvestment on the strip.
> 
> Water injection would on the other hand probably have suppressed detonation
> and lowered the intake temperature a lot. I guess that most of the
> performance would have been regained with water injection right after the
> intercooler.
> 
> A core with equal size but less mass would probably have helped a lot too,
> the HKS cores I have compared with spearco are about half the weight for a
> the same size. The cores I have seen from charged air systems are about half
> the weight compared with the HKS cores...
> 
> A water/air intercooler is also a good idea for dragracing, you don't even
> have to have a radiator for it. Use a separate water tank packed with ice in
> the trunk, then start the pump when it is your turn. At the end of the strip
> you kill the pump again. On the street the water will give the same benefit
> as the heavy spearco core give over the lightweight cores while on the
> street.
> 
> Other things that can make a big difference is an other turbo, a lower
> temperature termostat, a fan switch that makes it possible to run the fan
> regardless of temperature. An intercooler fan is hard to install on our cars
> but it would help a lot. A thermally isolated intake or one made of
> stainless steel is also a good idea. Aluminum is probably the worst material
> an intake for an efi car can be made of. Plastic is the best but stainless
> steel is a good compromise on our cars.
> 
> I really appreciate the report on this experiment, this way I know that I
> have to use a combination of a water/air intercooler and the big front
> mounted air/air intercooler.
> 
> I recived this link today from an other list, to my suprise the standard
> numbers are for a five cylinder engine with 86.4mm stroke.Unfortunally it
> seem to assume that all the water is evaporated before it reaches the
> cylinder.
> 
> http://members.home.net/pfahlgren/cars/turbo/glossary/turbo_calc.html
> 
> Jorgen Karlsson
> Gothenburg, Sweden.