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Bob -
Because I'm basically lazy, I simply cut and pasted my feedback letter to IPD regarding the VX cam I installed last summer (plus a few comments added , in brackets). Since that note was written, I also installed their sport exhaust (single, aft muffler, 2.5" cat-back pipes).
For minimal bucks and heartburn, I am thrilled with the power. It's no Turbo or V8, but a couple of weeks ago I literally ran away from another 92 245 going uphill on I-84 at 4 am... pretty sure he had an automatic (better final gearing than my stick), and I was accelerating at 85+ mph while he was falling behind. An added bonus is a really sweet sound on startup when cold... the rich running makes a cool sound!
Based on my research, if you wanted to avoid the cost of an adjustable cam gear, get some sort of bushing to advance the VX cam by 5 or 6 degrees... look around in the archives here for a source.
Good luck!
Re: VX cam experience
To the good folks at IPD:
In one of your recent catalogs you mentioned that you wanted to hear customers' experiences with your products. A week after installing a new VX cam with the adjustable cam gear, allow me to add mine.
The target vehicle is a new-to-me 1992 245 5-speed with 120,000 miles. The engine is in very good condition, and the former driver is a school secretary with no boy-racer notions, so I know it wasn't abused. The engine was externally cleaner than any I'd ever seen outside of a showroom. I bought the car for more than I wanted to spend but still a reasonable price, and I had set a total budget for the purchase and the inevitable repairs which come with any used car purchase.
After going through all the basics - oil change, new plugs, cap & rotor, plug wires, I started considering some performance tweaks. IPD sway bars & overload springs were swapped over from the 245 I just retired, and 15 inch alloy wheels (located on e-Bay) with new Yokohama Avid T-4's were installed. The front struts were replaced with Boge Turbo Gas, and the IPD upper tower reinforcing plates were added for insurance. (Note - the struts were a MAJOR pain to replace, unlike the 850 series.) Upper strut bars were added and the lower chassis tie bars will follow shortly.[now installed - 4/2002]
There was enough room in the budget for the a cam, and from the research I did on the Web regarding Volvo cams for the B230 engine it looked like the VX cam was the best choice. However, the feedback is that for street use the VX cam needs to be advanced 3 degrees, and indeed a "VX3" cam is offered somewhere on the market. The arrival of the IPD summer brochure offering a special deal on the VX cam packaged with the adjustable cam gear, timing belt and seals pushed me over the edge. Sold!
So Labor Day weekend arrived, and Saturday morning the project was begun. Since my car bore no evidence of ever having had a timing belt replaced, that task was primary, and the cam business would happen if time allowed. Once the front of the engine was stripped for the new timing belt, then the old cam came out (after first measuring valve clearances, more for reference sake, but just in case I need to revert to the original cam some time). Installing the new cam was a snap, although I was somewhat fearful that the higher valve lift would turn a non-interference engine into one where the valves would kiss the pistons. I cautiously rotated cam and crank independently to assure that no interference would occur.
One small consternation on my part was that I removed both the original cam gear and the intermediate shaft gear without marking them. Side-by-side they look similar, but one has round holes and the other has oval/rectangular holes. They both have the same number of teeth, and to this moment I'm still not sure which is which. One gear had a much thicker rim, and since the intermediate gear only drives a distributor and oil pump I reckoned the thicker-rimmed gear must belong to the cam. The thin-rim gear now resides on the intermediate shaft.
The timing belt installation was straightforward. I would add here a suggestion that first-time belt changers count the number of belt teeth between the timing marks on the cam and intermediate gears, and the number of belt teeth between the intermediate gear mark and the front 'key' (alignment mark) on the crank gear, just for "belt and suspenders" reference. On Brickboard there are frequent posts about timing belts being installed one tooth off… and the tooth-count method adds one more check on the process.
Now it's time to adjust the valves - first time on a Volvo for me. I used your rental "J-hook" tool to depress the lifters, but at first the shims refused to come out. Eventually I realized that the surface tension from the oil film between shim and lifter was substantial… but eventually the shims yielded to my now-deformed dental probe. I shimmed to the appropriate cold clearances, rotated the cam several times to insure the shims were seated, then re-checked clearances. My first pass measurement was 50% correct, and only 4 shims needed re-changing. Two more passes were required - I'm not sure why - and when all was said and done I had one valve with 0.001" greater clearance than specified. Since my vernier caliper is only accurate to 0.001", my engineering background suggests that this is probably close enough, and better too loose than too tight.
Buttoned everything up (save for the upper timing belt cover) after dousing the cam with oil (in addition to the liberal coat of assembly lube on cam lobes and bearings). I bumped the starter a couple of times for one last check before firing up - then went all the way. The car started right up as if nothing was different. I was impressed!
The next day, Sunday, was time trial day. I did have the foresight to do some timing runs with the stock cam before changing it. Since my 'new' car doesn't have a tach yet, I had established a low-rpm and a high-rpm range which corresponded to 30-50 mph in 2nd gear (3000-5000 rpm) and 30-55 mph in 3rd gear (1900-3500 rpm). For the driving I do, engine strength in the mid-range is of greater value than at screamin' revs. I have an 80-mile round trip on mostly country roads; I cross four ridge lines and there are a lot of sharp turns in this part of western Connecticut. My actual road speeds range from 30 to 70. I don't mind shifting gears, but a peaky power band is not what I was looking for. All but one hill can be nicely managed ay nothing lower than 3rd gear. I also do a fair amount of weekend highway driving, and it's nice to have power at cruising speeds in 4th and 5th. All this points to the lower-speed rev range being of greater utility to me.
OK, so here are my results:
[first col is 0-60 time, then 3rd gear 30-55 mph, roughly 1900-3500 rpm, then 2nd gear 30-50 mph, 3000-5000 rpm]
0-60 mph Low Spd30-55 mph, 3rd 1900-3500 rpm High Speed30-50 mph, 2nd gear3000-5000 rpm
Stock cam 12.5 sec 9.4 sec 5.2 sec
VX cam timed 0 deg 12.5 sec 10.0 sec 4.4 sec
VX cam timed +3 deg 12.5 sec 9.5 sec 5.2 sec
VX cam timed +5 deg 11.5 sec 8.6 sec 4.7 sec
Some disclaimers: the timing measurements were done on 3 separate days (air temps about the same); only the VX @ 0 deg and at +3 deg were back-to-back runs. The 0-60 times are 2-run averages, and shifts without a tach were done by ear and by feel. The 2nd and 3rd gear times are averages of 8-10 runs each.
[tach now installed]
Subjectively, the VX cam at 0 and 3 degrees advance had a neat feel… I could clearly feel the engine "get on the cam." Merging onto the highway in 3rd gear and accelerating from about 45 to 70 felt super, lots of power. But on the rest of my drive, hills formerly negotiated in 4th gear now required a downshift, especially with the cam at 0 degrees. The increase in torque was especially noticeable during the 0-60 runs when shifting into 2nd - the boot in the backside was much more substantial than with the stock cam. I was tempted to leave the cam at 3 degrees advance since it felt so nice… but what kind of test engineer would I be if I didn't expand the envelope? I moved the cam to +5 degrees, and now I get a completely linear feel - the power band is utterly the same from off-idle up to max. Not as entertaining, but now I feel the difference going up the 4th-gear hills, and there is s slight but noticeable improvement in top-gear passing at highway speeds. Fuel economy has not suffered and remains so far around 27 mpg. There is more valve clatter than before, but I attribute this to the sharp profile of the new came, and it is not objectionable to me. With solid lifter I am more nervous when I don't hear the valves!
If the budget allowed I would replace the stock exhaust system with your hi-flow unit, but I can't swing that right now. In the meantime, I am enjoying my "better than average" 245. I will also add that I remain quite pleased with IPD in terms of your offerings, prompt shipping, and overall care of the customer.
Best regards -
Gary Smith
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