I just read your post on info on puttin the SI motor in an HF and couldnt pass up on the response...I did a ZC swap into my 88 HF and was in the same place u were not too long before that..tryin to decide what to up my whoppin 62 horses to...the Zc (138 dynoed at my friend's garage) has made life alot more interesting on the road...at least it keeps the bigger cars in check. Yes 108 is a big difference from 62...but the ZC is a direct bolt on swap as well...and for the added 30 some horses...it was worth the time spent in pulling out the old one...just my two cents!