Please explain the effect chillers have on boost. I have been told that you loose 2 psi boost running the intercooler. We ran one of my engines last week on the the dyno . The pulleys should have made 7 psi on paper ... we had 5psi ( -2 psi). Is it from the cooling effect of the the condenced air charge ? Added volume ? Or a combination of both ?We ran a second supercharger on the same engine with same results.

Bob

The loss in boost is a measure of flow restriction. Since you lost 2 lbs boost in the manifold below the chiller, it is due to a greater restriction caused by the chiller. The chillers give you more power and safety margin by lowering the air intake temps. To take advantage of the cooler air, you will need to go a little smaller on the blower pulley to get back your 2 lost pounds of boost.

Did you have HP numbers before the addition of the chillers??

Sometimes even though you lost boost, you will make more power due tothe denser charge.


Smitty

Thanks Smitty !

My hp n/a was 616 @ 5700 ... 489 cid . I added the blowers and chillers at the same time.Hp is now 785 @ 5800 max torque @ 4500 of 780 foot lbs. Plans do not include turning the blowers faster . So 5 psi chilled is going to be like 3 psi unchilled as far as detonation goes?We saw that the a/f ratio was greatly effected just by changing water flow and pressure to the chiller ... so much that I'm concerned about running the engines in the boat with out monitoring a/f . Decided to install bungs in the tail pipes and gauges just to check the real world tune. We had 62 degree water on the dyno in and 86 degree water out. Interesting stuff for sure ...

The chiller cools the air/fuel charge. The denser charge takes up less room and therefore has less pressure. The chiller core may also create some restriction above the manifold.

If you took the chiller off, boost pressure would go up, but the actual amount of molecules in the air/fuel charge would be the same.