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I am pretty sure the head gasket on my recently rebuilt B30A has failed. While I am going through the work of pulling the head, I thought this would be the opportune time to warm up the engine a little. Now for some specifics to recap:<p>Pistons .015" Over<br>"C" Cam<br>Head has been slightly surfaced to true (Note: I recall measuring the head thickness after the machine work and getting a measurement thicker than the stock A spec... curious)<br>Stock A head with new valves and springs<br>Stock A exhaust system<br>Plumber's nightmare integrated manifolds with SU HIFs, BBB needles<br>1975 Stock Electronic Ignition<p>I would like to bring the HP and torque up to or slightly exceed the B30E numbers while (hopefully) retaining Volvo reliability. This is what I am currently considering: bring compression ratio up to 9.8-10.0:1, trade the "C" for the "K" cam and have a local shop build a larger bore exhaust system.<br>Which direction should I pursue? <br>-Compression ratio increase? How high can one go on pump (91 octane) gas? <br>-Hotter cam? Will changing to the "K" cam radically change the tractability of the engine? Can the A head and stock manifold support the cam? Would it be worth the trouble and expense to fabricate a tri-carb manifold?<br>-Port and polish on the head? (I would like to retain the A head.) <br>-Larger exhaust bore? How large? <br>And, if I am seeking higher performance, which head gasket should I use A/E/F (yes, I know this comes into play with compression ratio)?<br> <IMG NAME="icon" SRC="http://www.vwvortex.com/zeroforum_graphics/screwy.gif" BORDER="0"> Confused in MT,<br>Nick
 

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Re: Seeking More Power Out of a B30 (Phaedrus)

I've built a bunch of performance B18s and B20s, but never a B30, so I can't answer too specifically. In general, though:<p>A good porting job will reward you, and should be the foundation for all other mods.<p>Use the thinnest head gasket available. Bringing the flat bottom of the head closer to the pistons is beneficial, over and above raising compression. With a .030" gasket and the slight overbore you have, 51cc combustion chambers will give you 10:1 compression. You can get away with that running premium gas with a C cam or any other cam with more overlap.<p>I'm not a fan of the K cam at all. If you can get a D cam for B30, go with that instead. You'll have no noticeable loss of low-end power, and a good improvement in the mid-range and high end. You can keep the regular valve springs with a D.<p>There's very little gain, or no gain at all, to be had from a three-carb setup. If there's an alternative to the plumber's nightmare manifold, though, use go for it.<p>A 2-1/2" exhaust would not be too large.
 

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Re: Seeking More Power Out of a B30 (Phil Singher)

Might want to determine why the head gasket failed.<p>Consider bringing the engine up to original specs with all mechanicals in perfect shape then go with Phil's ideas on performance.<p>The 1975 B30 ignition and fuel setup by Volvo compromised the performance of the car in a big way. The carb version in 1968 with a manual would suck up a '75 'Vet to the first red light (are they any other colors but red?).<p>A custom intake manifold can be used to stack any single-carb setup desired. A hand-built exhaust header will extract some serious torque unless poorly executed. A hot distributor/coil arrangement from Mallory is still out there but very $$$. Air flow in and out is the key along with proper air-fuel/spark setup. High CR is the key here as you can manage pre-ignition with fuel and spark settings and/or higher octane/water injection.<p>Most B30 enthusiast are aware of the car's limits due to extreme front weight bias.<p>Don't let that stop you.<p>George Dill<p><A HREF="http://www.google.com/search?q=volvo+performance+%22B30+engine%22&hl=en&lr=&safe=active&as_qdr=all&start=10&sa=N" TARGET="_blank">http://www.google.com/search?q...&sa=N</A><p>
 

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Re: Seeking More Power Out of a B30 (Phaedrus)

Beware of three carbs on that B30, it is harder to tune. If you use SU's the center needle will be different from the other two. The intake air flow pulses are different. You'd be better off with two SU's or go with three two barrel side draft webers <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/tongue.gif" BORDER="0">
 

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Re: Seeking More Power Out of a B30 (gdill2)

George:<br>Here's the story on the headgasket:<br>All summer, I have been trying to get the 164 in tune. At the end of July, I finally found the right mix to where the engine was happiest. It ran cool, had power in the right areas of the powerband and got relatively good milage for a carbed B30. <br>In mid-August I replaced the upper radiator hose (the last one was kinked and I finally found a suitable replacement; this was the same time period as the Heat and Tuning questions I posted in the 140-160 forum) and changed the coolant, also properly bleeding the system. I added Redline Water Wetter to try and keep the engine cool. After this work, the temp gauge stayed between the "E" and "M" of the gauge, even in 100 degree F heat. A week later I was taking an cool early morning drive, about 60 degrees F through mixed in-town and highway driving. When I slowed to stop at one point, I noticed the temperature gauge was pegged in the red. I turned the heater on full and drove slowly home and I have not driven the car much since. Ever since that morning, there is excessive moisture coming out of the tailpipe upon start-up including steam/ white smoke until the engine is fully warm. I can feel air bubbles in the upper radiator hose when the engine is idling. Also, there are grayish fluffy deposits in the expansion tank above where the coolant is at it's highest level (Note: I noticed these deposits in the tank shortly after the rebuild, so I wonder if the gasket ever sealed(?)). Lastly, I recently bought an infra-red pyrometer and measured a 15-20 degree F increase in the temp at the center of the block (190 to 205 degrees). Given all of this, I am assuming the head gasket has failed.<p>Now, regarding your post, would you recommend going back to the earlier points-style distributor? From what I remember, the early distributors have 12 degrees total advance, while the late ones have only 10. I know Volvo changed the advance curve for the '75 models, but I thought the increase in voltage at the plug would somewhat counteract this... <IMG NAME="icon" SRC="http://www.vwvortex.com/zeroforum_graphics/screwy.gif" BORDER="0"> I was under the assumption that the drastic reduction in performance was due to the 1 point lower CR for the '74 and '75 models. And prior to the head gasket failure, the engine was running extremely well. I am not looking to build a monster B30, I just would like a little more oomph to keep up with modern traffic.<p>Phil:<br>When it comes to porting, should I seek out someone familiar with OHV Volvo engines, or can I trust someone familiar with domestic engines if I can point out where in the head and the amount to remove? Would you have anyone in the Volvo circuit you would recommend to do the job?<p>Thank you very much for your replies,<br>Nick A.
 

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Re: Seeking More Power Out of a B30 (Phaedrus)

With apologies to Sr. Dill, I am not convinced that the 1975 electronic ignition is seriously lacking. The 1975 mods to fuel injection and lower compression ratio are probably the major culprits. Whenever the points system in my 69 164 starts giving me trouble (and at almost 300,000 miles it is on its third distributor) I will install the '75 ignition system and tune accordingly.<br>I have lusted for a 3-carb system, and in fact had an AQ170 system for a while but did not install it because of the interference with the exhaust manifolds. I ultimately sold it to a boat owner in Florida. I am still looking for an AQ165 manifold (uses sidedraft carbs) but have yet to even talk to anyone who has seen one in the last 20 years. Dominik Benz of the German 164 club has 3 SUs on his 164 and a couple pix on their website. He cites "brutish low speed torque". With European gas prices I wonder how much he can drive it. I have two HIF6s on mine now with the nightmare manifold.<br>The intake ports neck down pretty small just inside the valve seats. I believe (with no way of accurately measuring results) that opening these up and making sure the manifolds match the ports probably improves flow. I suspect that there is some help to be had in the exhaust also since this is the weak area in B20s and the B30 ports are no bigger.<br>I've run the IPD 7002 cam (6 cylinder version of 7001/Isky VV-71) in mine for about 20 years with good results (other than a couple of defective ones freely replaced by IPD - welded lobes were soft). REALLY helps performance above 3000 rpm probably to 6000 in spite of the manifold. Does great things for fuel consumption too. With my lead foot I could get around-town gas mileage in the range of 10-11 mpg. Unfortunately there arose a generation at IPD that knew not Joseph nor the 7002 cam......<br>I believe the D cam would be good or if you could persuade Isky to get you a VV-71 grind that would be good also. You might have to go to GCP or KGTrimning to get the D cam. Far as I know all or nearly all 164s came with the C cam which is good but modest. When I checked with KGTrimning I was looking at about $350 for the cam and another hundred for shipping. With the dollar down these days it could be worse.
 

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Re: Seeking More Power Out of a B30 (Walrus3)

The more user-adjustable a system is the better for squeezing out the max performance. This is true for spark, fuel, intake, exhaust, brakes, etc. Once you get a front-heavy car rolling it is nice to be able to stop safely and quickly. My '68 142 had the best brakes of all my pre-ABS Volvos. This was due to relatively light weight, an excellent braking system and fat, grippy tires.<p>This discussion is more about go than stop but keep the brakes in mind as you make mods.<p>Head gasket failure symptoms can be aped by improper seating of the water pump o-rings on the head surface. Wrong o-rings will do the same. A common oops is to use a very thin head gasket and the "tall" o-rings - this will eventually leak everytime.<p>Proper final head assembly methods must be followed. Once the engine is started for the first time run it just long enough to reach operating temp then re-torque EVERY head bolt to spec. After a few hundred road miles (or equivalent shop time) check all systems then re-torque ALL head bolts again. Yes, this is a PITA, but not a step to skip.<p>Coupla more items...<p> - Head gasket has just one position to fit properly<br> - Be sure no manifold studs extend into any head bolt thread area<br> - Use new correct head bolts and avoid washers<br> - Use a longer head bolt for ac flange<br> - Be sure your torque wrench is ok<p>My usual look at these projects is for the doer to visualize his/her final product then make all efforts in that direction.<p>George Dill<p><BR><BR>
<i>Modified by gdill2 at 12:11 PM 11-6-2007</i>
 

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Re: Seeking More Power Out of a B30 (gdill2)

<A HREF="http://www.kgtrimning.com/KGTRIMNING162005web.pdf" TARGET="_blank">http://www.kgtrimning.com/KGTRIMNING162005web.pdf</A><p>
 

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Re: Seeking More Power Out of a B30 (Phaedrus)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>Phaedrus</b> »</i></TD></TR><TR><TD CLASS="quote">When it comes to porting, should I seek out someone familiar with OHV Volvo engines, or can I trust someone familiar with domestic engines if I can point out where in the head and the amount to remove? Would you have anyone in the Volvo circuit you would recommend to do the job?</TD></TR></TABLE><p>The only guy I know who has experience porting B30 heads specifically is David Hueppchen (it's "Hipken," and don't call him Dave) at OJ Rallye Automotive in Plymouth, WI. Google and ye shall find...
 

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Re: Seeking More Power Out of a B30 (Phil Singher)

From <A HREF="http://www.vclassics.com/ojrallye.htm" TARGET="_blank">http://www.vclassics.com/ojrallye.htm</A><p>--------------------<br>OJ Rallye Automotive<br>P.O. Box 540<br>Plymouth, WI 53073<br>E-mail: [email protected]<br>---------------------------<p>Keep in mind that a mirror-smooth surface is not always the best for moving a medium through a pipe.<p>George Dill<p>
 

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Re: Seeking More Power Out of a B30 (Walrus3)

Thanks for all the replies!<br>I have more questions about the cam. The only readily available mild performance cams for the B30 are the "P" and "K". The "P" would yield gobs of torque, but this cam is not really suitable for a road car. I have been using this site to compare cam profiles (assuming the B20 and B30 cams are the same...):<A HREF="http://1800philes.com/ianr/_superlist_grinds.html" TARGET="_blank">http://1800philes.com/ianr/_superlist_grinds.html</A>. With this list, it appears the "D" and "K" cams are very similar with the "D" having slightly more duration. The "K" has less overlap and I am guessing this would be a milder cam. Now, is the "K" profile enough of an improvement to be recommended or should I try advancing/retarding the "C" cam I already have? (I hope I am remembering this correctly: advancing the cam improves horsepower and retarding the cam improves torque. Please correct me if I am wrong!) And while I have mentioned the cam list, can anyone explain the Valve Events sections on the right side of the chart? Are there any other modifications to the valve train that I should consider?<p>Walrus3: your post is encouraging as to what I mild performance 164 can be! Did you change the valve springs with the upgrade to the VV71 cam or are the stock ones adequate? <p>For the time being, I have decided not to pursue the AQ165/ tri-carb manifold. The combination of improper power pulses, cost of fabrication, and the high price of gas (Premium hit $3.289 a gallon the other day... Ouch.) have steered me away from the project. Will the SUs need a needle change with the performance upgrades? Will the stock manifold tolerate these mild upgrades?<p>Phil: Thanks for the recommendation. I will talk to David as soon as I get some free time.<p>Thanks again,<br>Nick A.
 
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