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Fellow members, I have a new Tomie head gasket going on a 800 hp 26/30. What method and torque values should i use to pull the head down nicely. Using new ARP studs. I have the manual for rb 26 GTR, but i wouldn't have thought i use the same values ? your help is appreciated. Thanx B)

Require the above as i have lost mine some where in the garage or i have a Phantom parts pincher? I'll pay freight. Any help appreciated. Perth WA Thanx

$300 for the gate

Yes the condenser is the part you mentioned- freight to you would be around $25.00 i would say.

Sorry about that , have now rectified.

(Use this as a guide for new threads. Delete and/or copy the fields as needed - dont forget to add your location in the description field above. Delete this message) Item:See Below Location:Perth Item Condition: all good Reason for Selling:surplus to change in build Price and Payment Conditions:directdeposit preffered Extra Info: Contact Details:0429168473 ories) Reply to this topicStart new topicStart Po Oil catch new stainless, sight glass , nice quality $100 Gtrgearbox in perfectcondition - bought a dogbox $1000 Timming belt RB 26 , 2000km"s new $50 GTR 342 plenum , excelent cond $280 sold GTR 32 fuel rail and reg $80 VDO 25 lb boost guage $50.excellent Sold GTR 32 Radiator and cowling $200 Very good cond A/C condenser and compressor $200 Good working order Comp sold Gtr 32 front rotors - need a skim $100 RB 26 cam pulleys $50 Sard blow off $120 Turbo smart manual boost control still in box $50 Various stuff from under dash, evaprator heater, servos and baffles

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PM me if you have.

Compression Ratio Information / Calculation / Comparison Submit corrections and additions to this information to The Olds FAQ Compiler. Information The change in horsepower due to the change in compression ratio is relative but not directly proportional. That is to say that a change from 8:1 to 9:1 will give you a larger increase than would the change from 13:1 to 14:1. I seem to recall for every one point change around 7:1, that is the change from 7:1 to 8:1, would be slightly more than a 3% power increase. Once you get up to around 13:1, that same one point change is only good for about a 1.5% power increase. The rule of thumb for the compression ratios run in most street engines is: for every point change in the compression ratio your power output will change by 2%. Using this rule of thumb on an engine that produces 400 hp, every 1 point change in compression ratio will result in approx. a 8hp change in output. One thing that you have to remember is that this is a static model. The only variable changing is the compression ratio. Most of the time when a compression ratio change is made, significant other factors are changed which can significantly affect power output. On avaliable pump gasoline it probably could be argued that your power might actually increase. This would be true if your compression ratio were high enough to force the use of a retarded timing curve (due to pre-ignition). The TRW L2323F forged piston which is rated at 10.25:1 comes out much less if you were to actually compute the mechanical compression ratio. Two factors that reduce the mechanical ratio are the as follows: 1. The steel shim head gaskets Olds used had a compressed thickness of only .017". The common Felpro head gasket is .043". 2. When you have a valve job performed, the valves have their margin reduced, reducing their slight protrusion into the combustion chamber. Valve seats are slightly recessed into the head by the grinder. Both of these increase the head's combustion chamber. If any or all seats are replaced, this could go either way. These two factors can increase your combustion chamber volumn by 5 to 7 cc's. This is enough to significantly change the compression ratio. Consider the use of the car when determining the compression ratio. Your camshaft profile probably has the most significant impact on what mechanical compression ratio you should run. A longer duration camshaft will allow you to use higher mechanical compression ratio pistons because it lowers the effective compression ratio by keeping one or both valves open slightly into the compression stroke. Be careful about the effects of production tolerances on compression ratio. Simply selecting a set of pistons labeled as 9.0:1 is not enough - you have to take into account the real combustion chamber volume, head gasket thickness, piston dish volume, and piston deck height. In reality, these dimensions are usually on the large side, resulting in less than the advertised compression ratio. While this is certainly safe from a detonation standpoint, it is not particularly healthy for performance. The bottom line is that during any quality engine rebuild, it pays to take the time to check all of the factory dimensions. You may decide that it's not worth the time and expense to correct discrepancies, however at least you'll make that decision consciously. [ Thanks to GABowles, Joe Padavano for this informatiton ] Calculation Put the head on something so you can move it around, V- type stands work well. Install a spark plug and tilt head so you have high side. Make a cc'ing plate out of a piece of clear plastic by drilling a ¼" or so hole in the plastic. Put a thin coat of grease on the head or piston to be cc'd. Smush the plate onto the head or piston, with the hole at one edge of the chamber. Measure how much fluid will fill the chamber. Water with some dish soap helps to break the surface tenson of the water. The air will self purge as you fill the chamber. Sometimes you have to tap the head a little to get rid of the bubbles. A Burette is probably the nicest setup. A 60cc, or a 20cc syringe for pistons with a small dish, can be used with good results. An accurate the sphincter of the universe-baster would work just fine, graduated in cc's, or you can convert to cc's. Elevate the hole, so it's at the top of the chamber, and the water [or oil or whatever] will drain away. Water can be used on the bench-done parts, and engine oil when cc'ing the total clearance volume on the assembled engine. Typical Olds 425-HC-T Engine CRatio specifications: 4.125" Bore 3.975" Stroke 0.015" Deck clearance [piston top is this far below block's deck surface] 4.250" Gasket hole diameter 0.045" Gasket thickness when installed 2.750" Piston dish volume 0.045" Piston dish depth 10.5:1 Stock CRatio. [ Thanks to Chris Witt, Walter for this information ] Volume Formulas Changed cc's to cubic inches by dividing by 2.54^3. Then, using CR=BDCV/TDCV, where BDCV = Volume at BDC, = TDCV + piston displacement TDCV = Volume at TDC, = amount of oil required to fill the combustion chamber at TDC, as measured per above. piston displacement = pi/4 * bore^2 * stroke pi = 3.14159 Bore = 4.125" Stroke = 4.250" 1 ml = 1 cc From the above, we can easily calculate: cc in^3 What 6984.0 425.00 Total engine displacement 870.5 53.10 Cylinder displacement [piston swept volume] 4.4 .27 Piston dish volume 3.3 .20 Deck clearance volume 10.5 .64 Gasket hole volume [stock is more like 4-5cc] 18.1 1.11 Total Clearance Volume, except head 98.1 5.99 Total Clearance Volume, including std. 80cc head Which yields a CRatio of 9.87 with an 80cc head, or 10.78 with a head shaved 0.045" [head loses 1.01cc per .005" cut] Note: each cc of volume in the Clearance Volume affects the CRatio about 0.1 point at these numbers [bore, stroke, etc.] Comparison An overbore of .030" or .060" makes a difference of up to about 3% in the cylinder displacement, which is practically negligible in the grand scheme of things. Amount to cut the head in order to achieve the stock advertised compression ratio: Bore: Std .030 .060 C/R Engine .032 .026 .019 10.5 425HC Toro/SF pistons, 80cc heads .033 .026 .020 10.25 425HC Std. 455 HC pistons, 80cc heads .040 .033 .026 10.25 455HC Std. HC pistons, 80cc heads .090 .082 .074 9.00 455LC Std. LC pistons, 80cc heads .152 .147 .142 10.25 350HC Std. HC pistons, #8 [79cc] heads .078 .073 .067 10.25 350HC Same pistons, #5-6-7 [64cc] heads .134 Why bother? 9.00 350LC std. LC pistons, #8 [80cc] heads .060 .053 .047 9.00 350LC same pistons, #5-6-7 [64cc] heads .047 .042 .036 10.25 330HC HC pistons, 64cc heads .061 .055 .049 9.00 330LC LC pistons, 64cc heads .037 .030 .024 10.5 E400HC dishless flattop pistons, 80cc heads Early 400 engine, 4.000 bore x 3.975 stroke .049 .042 .036 10.25 L400 HC pistons, 80cc heads .051 .043 .035 9.00 L400 LC pistons, 80cc heads Well, after some careful measuring it was discovered that the 425 Toro/Starfire engine had higher compression pistons than the std. 425 HC. At first glance they appear identical, but the T/S pistons have a slightly shallower dish, like .040" rather than .060", which cc'd out to 4.5cc for the T/S pistons and 7cc for the lesser-car pistons. Each cc is about 0.1 on the compression ratio, so the Toronado/ Starfire pistons offer about 0.25 more compression ratio, all else equal. Rule of Thumb: Basically, to get the 'advertised' CRatio with today's .045" gasket, you have to cut the heads about .050". Since the gasket is about .025 or .030" taller, you are really only moving the heads .020 or .025" closer to the block- hardly worth milling the intake/head face to match. Also, there's no way to get even a 9:1 CRatio with #8 heads on a 350. In fact, with low-comp pistons, the CR calculates out to about 7.5:1 !!! For a 9:1, you'd have to mill a ridiculous amount, like 0.125", off the heads. Yuck. [ Thanks to Chris Witt for this information ]

What do they do?

Peter, Steve , Daniel, thanks for your input. Welding the crank ( even with top crank specialist is not an option to me ) purchased a jun collar today and crank is out.

fare comment guys , only trouble is , the crank has been metalaxed ( spellings wrong ), balanced , journals opened etc etc. The external pump that you suggested Steve sounds viabel , need more info if you don't mind Steve.

far comment guys , only trouble is , the crank has been metalaxed ( spellings wrong ), balanced , journals opened etc etc.

Steve, no air con , no factory fruit at all , just about drag specs. External pumps , tell me more please.

How nessacary is it to do ??

Thanks for that, can't see why cant locate as engine is on the bench , How has it been so far?

Dear people, I have conducted a search and found no info, so i need your oppinion. I am currently building a meduim to high hp rb 30 /26. I have assembled the bottom end and all good gear has been used . BUT dam it i did not get the crank oil pump collar widend. No one over here in WA does it any way. I have just been informed that this was a crucial mistake and my N1 on the standard crank will not last 5 minutes , i tend to disagree. Is it mainly in tired r32 rb26 engines that they let go ? If this is the case what if i replace every , say x amount of km's. Will this help or is it simply an hp issue. Sometimes i wonder if some things i get told from tune shops are simply a "turnover factor " . Please enlighten me on this if you would not mind , are there any alternative measures i can take . some one mention a collar that can be bought or made . Thanx

Dear people, I have conducted a search and found no info, so i need your oppinion. I am currently building a meduim to high hp rb 30 /26. I have assembled the bottom end and all good gear has been used . BUT dam it i did not get the crank oil pump collar widend. No one over here in WA does it any way. I have just been informed that this was a crucial mistake and my N1 on the standard crank will not last 5 minutes , i tend to disagree. Is it mainly in tired r32 rb26 engines that they let go ? If this is the case what if i replace every , say x amount of km's. Will this help or is it simply an hp issue. Sometimes i wonder if some things i get told from tune shops are simply a "turnover factor " . Please enlighten me on this if you would not mind , are there any alternative measures i can take . some one mention a collar that can be bought or made . Thanx

Do you ? Really! Explain a few pro's and con's then if you wouldn't mind.Why wpould you have both?

So is it better than a quality metal grommet style gasket or simply cheaper because one can use a cheaper gasket ? I assume that one could not use a metal gasket if it hasbeen O ringed?

This thread was started some time ago but read till end for follow up. I here this expression frequently, some times in different context . What does this mean exactly please? How do you do it? Why is super gromet style metal head gasket not sufficient? Or is it. <_<

Far from a simple job , if any one purchses the engine , feel freee to contact me for help.

Yeh we do. Duty - who pays that. $400 is my offer .