Would help to know specs on the car...Turbo, GLE 16v, standard 4....manual or auto. What are you going to use the car for? Daily driver (see below as removing that stuff will get you a big Federal headache and ??? if caught), race car, etc.

If daily driver, don't. It's illegal. Some suggestions below.

If you don't have a Turbo with the manual I'd say look at an engine conversion. Nothing against autos, but Volvo's auto trannies aren't exactly the most efficent and it shows in the large gaps between their auto and manual cars times ( 1980 to early 90's). Even as recently as the 98 C70 there was a 1/2 to 1 second gap between the auto and manual versions on 0-60mph. 6.4 on the manual and 7.1 on the auto. Of course, many facotrs contribute to the time but all the tests show a similar gap.

Somone else posted about $3000 for rebuild and $2000 for heads...this MIGHT get you to the 150-170hp level on a stock engine....but for 5000 can also do a nice fuel injected chevy v8 (sky is the limit on HP with those) with a 4spd auto or 5/6 speed manual. You could also look at a Chevy 3.8 v6 out of newer camaros...200hp, and relatively cheap to find used compared to an LT1 v8 or TPI v8. You could probably buy the v6 an slap on a Whipple supercharger for the same price as buying just the LT1 V8, and get the same if not slightly better performance. LT1 were 275hp, and with a Whipple the v6 would make 300hp.

Here's a sight that has parts for the V8 conversion in Volvos and other cars/trucks:
http://www.jagsthatrun.com/

Here's a link for a complete drive train from a 95 Firebird (275 hp LT1, 4l60E auto, harness, etc.) It is currently 2700$ and ends in 12 hours.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1864254236


Good Luck
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MD