Finally, the "Lessons Learned" from my 940 sedan project. Take heed from the voice of experience!
1.
Survivor Car - As hindsight is 20-20, I now know that I should have waited for a much better vehicle as a starting point. I know these cars are now ~ 30 years old, but I continually see proof that true survivors exist.... one owner, all service records. You will be much ahead of the game if you search and WAIT until you find one of these for your project. Why you ask? My sedan had a mild mailbox encounter and required a front fender, hood as well as pass. rear quarter repairs to make it look right. Between 2 events at my local body shop, I spent more than $5K on body & paint work. Save yourself all this expense by buying a survivor car.... polish the OE paint and be thankful for it.
2.
95 940 brake booster/pedal - The factory brakes on my 92 always left me underwhelmed.... and expecting more from them. Once I learned of the 95-98 revision to enhance the brake booster/pedal mechanism, I sourced one. Best braking feel the car ever had! It actually had braking performance like a modern car should have.
3.
Ben's coilovers - I fooled around with revisions to "sport suspension" for most of the time I owned the sedan. Near the end of the project, I invested in a full coilover system from Ben. I can only say the change to the vehicle was
"transformational". My advice to you is don't waste your time with "sport springs" from IPD et al, but save your $$$ and go straight to Ben. Period.
These remaining lessons are specifically related to redblock powertrain vehicles, and presume retention and optimization thereof.
4.
19T Turbo / TD04 MITSU - Early and midterm in the project, I ran a Garrett turbo. Finally I saw the light and built a 19T MITSU for the sedan. This is nothing but WIN for vehicles less than 300 HP. The response of the 19T is instantaneous, the OE oil supply lines and drain return lines work flawlessly without leaks (anything else you cobble together will leak oil.... I know). I do recommend this turbo with the 3" V-Band TIG welded to the correct exhaust housing, as I did it. For my money, the best bang for the redblock buck is this 19T with a 3" downpipe.... what is behind that I feel is of limited consequence. I ran the stainless TME 2.5 exhaust backward.... and don't believe for a minute a "full 3" system" gains you much of anything in these less than 300 HP applications.
5.
do88 FMIC with pipes - I made this upgrade simultaneously with the 19T and 3" downpipe.... so I cannot separate them from the impact each had on performance. I know the evidence strongly supports such a design of FMIC. While the old factory plastic charge cooler will hang together for one pass, they then begin to heat soak and your charge temperature will continue to elevate. This is a fact, search for the evidence yourselves. I bought the full "big pipes" setup right up to the throttle body, and recommend it. Be sure to use proper T-bolt clamps as I did, just like they use on turbo diesels.
6.
AW71 "accumulator mod" - My 94 vintage Japanese automatic shifted flawlessly and took a steady diet of 18psi in doing it. I learned late in this project that TOYOTA used the same family transmission for millions of their vehicles. Probably wouldn't last that long for the 300+HP or drag racing guys, but that wasn't me and I suspect it isn't the case for the majority of you all. Also use the IPD oil flush kit, keep your trans running on clean cool fluid and it will serve you well. Oh yes, if possible find a 95 vintage AW71 which is even more robust.
7.
4.10 final gear ratio - The NA 9 series vehicles all (to my knowledge) came factory fitted with this DANA rear end. The vast majority of them had an automatic in front of them so they are in near perfect condition. I also believe most if not all of them came factory with a G80. Compared to the common 3.73 gearing in Turbo cars, this provides a +10% torque increase to the rear wheels! Those of us who drove these RWD redblocks know they aren't economy vehicles.... and yes while the RPM increase 10% (remember the relationship between HP, torque and speed) the fuel consumption difference is marginal. My sedan was happy to buzz down the freeway at 75mph with the 4.10 gear. Getting torque to the rear tires is what it's all about friends.
8.
OE Cams, run "straight up" - All the aftermarket cams fall short of wearing like an OE cam. Find the right OE cam for your turbo, and use the 93+ round tooth belt / gears for bulletproof reliability. I ran an IPD Turbo cam for all those years, and was disappointed when I learned how soft they were and that they wear at an alarming rate. Again, OE reliability for the win. Oh yes, don't waste your time with "BLING" such as cute anodized adjustable timing gearsets..... really just eye candy and IMO gain you relatively little in engine HP.
9.
93/94+ 9 series accessory bracket - I ran a couple of the earlier brackets, the type with about a dozen rubber sleeves to isolate the noise. Within 6 months, I had loose belts, belt squeal. Finally put on the last version with the rock solid AC compressor mount, and the belts were stable and didn't require continual adjustment or replaced bushings. Forget those blue poly sleeve bushings, go straight to one of these late design accessory mounts.
That's it folks! Most of these
lessons learned apply to the 2 series cars as well.
While I am now retired and focused on other things, I am not completely out of the Volvo game: