Re: Compression ratio testing

[Rob P]

Note: Obviously I won't be using this motor (L20B) for PRC (Production Rally Class) rallying as we all know the biggest donk put into a 1600 (510) by the Datsun factory was the L18 motor. That is my next project though, an L18 powered, bush rally beast for the ball-bearing gravel roads here in WA. Plenty of sideways action, woo-hoo!   Rob P ----- Original Message ----- From: Rob P To: [EMAIL PROTECTED] Sent: Tuesday, December 03, 2002 10:47 AM Subject: Re: Compression ratio testing Yeah I don't think it matters. When i talked to a guy at Datrally (I think it was) he said most people are building L18s for PRC rallying and the final capacity doesnt matter, so long as you use the L18 block.     Rob P ----- Original Message ----- From: Terry Rudd To: [EMAIL PROTECTED] Sent: Monday, December 02, 2002 7:28 PM Subject: RE: Compression ratio testing Regulations used to vary a bit in class racing and I haven't a clue what they are in 2002 - in my day you were allowed stock bore +40' (1mm) regardless if this took the capacity over the limit. A good example was when Bathurst was a capacity class race, I can't think of any Nissan example in that era but the infamous Celica GT 2000 18RGU engine was 1960cc in stock form but plus 1mm took it just over to 2004cc and that's what the Williamson Celicas raced with - it is a very over square engine (only 80mm stroke) so +1mm bore was +11cc per cylinder.   3.5" (88.9mm) bore L20B engines were very common rally engines so they can be reliable if built right i.e. sonic tested and bored round and not bored square or oval and half decent quality pistons used. The Japanese block was the best from what I've seen out there. Go for it and see what happens, you'll never know unless you give it a go and in reality there's not much you can do about it once it's bored that far anyway.   regards Terry -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Rob P Sent: Monday, 2 December 2002 10:02 PM To: [EMAIL PROTECTED] Subject: Re: Compression ratio testing When I bought the motor, I asked the guy twice whether its capacity was over two litres and he said yes both times. Basically I wanted to legitimately compete in under 2 litre class competitions. Maybe the guy lied or just did'nt know,as he did'nt build the motor either. Neither did the guy he bought it off. Do reckon it's "scarey" because wall thickness is a bit thin on a 89mm bored block?   Regards, Rob P   ----- Original Message ----- From: Terry Rudd To: [EMAIL PROTECTED] Sent: Monday, December 02, 2002 6:39 PM Subject: RE: Compression ratio testing Still not quite right Errol - the second 60 should be 45 also, the result is correct. 2140cc L20B block is 89cc bore - scary.   regards Terry -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of E Smith Sent: Monday, 2 December 2002 6:57 AM To: [EMAIL PROTECTED] Subject: RE: Compression ratio testing Apologies, I'll read the post better next time.   At 45 cc that means ((12.84 x 45) - [Terry Rudd] 45 (60 )=532.8 cc which would make it a 2140 engine. A much more likely figure.   Cheers, Feral Errol <http://www.datrats.com.au/> -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Rob P Sent: Monday, December 02, 2002 1:01 AM To: [EMAIL PROTECTED] Subject: Re: Compression ratio testing Cheers Errol, You may be right, as Terry has also cast doubts over the validity of the figures. However, where did you get the 60 in your formula? I cc'd the combustion chamber with the head on the block and this included the chamber volume and the remainder of swept volume (0 cc) and total was 45cc at TDC. The flat tops must be flush with the top of the block, basically.   Regards, Rob P   --membersozdat------------------------------------------------------- OZDAT Mailing List Please Note:- Send (un)subscribe requests to [EMAIL PROTECTED] Send submissions to [EMAIL PROTECTED] No unauthorised redistribution of this email http://www.ozdat.com/ozdatonline/index.htm http://www.ozdat.com/ozdatonline/listindex.html http://www.mail-archive.com/membersozdat@datascribe.com.au/ --------------------------------------------------------------------- --membersozdat------------------------------------------------------- OZDAT Mailing List Please Note:- Send (un)subscribe requests to [EMAIL PROTECTED] Send submissions to [EMAIL PROTECTED] No unauthorised redistribution of this email http://www.ozdat.com/ozdatonline/index.htm http://www.ozdat.com/ozdatonline/listindex.html http://www.mail-archive.com/membersozdat@datascribe.com.au/ --------------------------------------------------------------------- --membersozdat------------------------------------------------------- OZDAT Mailing List Please Note:- Send (un)subscribe requests to [EMAIL PROTECTED] Send submissions to [EMAIL PROTECTED] No unauthorised redistribution of this email http://www.ozdat.com/ozdatonline/index.htm http://www.ozdat.com/ozdatonline/listindex.html http://www.mail-archive.com/membersozdat@datascribe.com.au/ --------------------------------------------------------------------- --membersozdat------------------------------------------------------- OZDAT Mailing List Please Note:- Send (un)subscribe requests to [EMAIL PROTECTED] Send submissions to [EMAIL PROTECTED] No unauthorised redistribution of this email http://www.ozdat.com/ozdatonline/index.htm http://www.ozdat.com/ozdatonline/listindex.html http://www.mail-archive.com/membersozdat@datascribe.com.au/ --------------------------------------------------------------------- --membersozdat------------------------------------------------------- OZDAT Mailing List Please Note:- Send (un)subscribe requests to [EMAIL PROTECTED] Send submissions to [EMAIL PROTECTED] No unauthorised redistribution of this email http://www.ozdat.com/ozdatonline/index.htm http://www.ozdat.com/ozdatonline/listindex.html http://www.mail-archive.com/membersozdat@datascribe.com.au/ ---------------------------------------------------------------------