When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Do they still offer them? I tried a little over a year ago to find them and no one could get them. I know at one time they were in the catalog but, I have never seen a set.
If he were to compare the dyno graphs overlaying the 20hp he got up high he lost down low. Usually around 6grand is the gain lossing 20 around about 3grand. Give or take a few hundred rpm.