compression ratios and supercharging

[simonavo]

Hi all,

Im fitting an eaton M62 Blower to my 2500 carb engine and was considering CR's and not wanting to hole a piston etc was looking how to lower it slightly. Is it feasable to fit 2 head gaskets to raise the chamber top. Other way to go is to machine the head chamber out , but how much to do it. Would using super unleaded enable a higher cr. I guess its all trial and error, ie not pushing too much boost at first and seeing if detonation occurs. Having read the other posts on the subject I was wondering if anyone has actually done it and has any tips. The Moss supercharger is an example to follow , as they have probably have done the research, does anyone know the setup/spec, how they have limited the potential for damage. I presume they have a disclaimer regarding blow ups occuring?

Thanks

Simon

[ken]

Hi simon having some time playing with turbo charged engines i would not use two head gasgets. you would need to drop the compression down using the pistons. find a set with a dish in the top. ford rs turbo engines run about 7:1 compression and between 6-10 lbs boost. I have heard some fiat or masda mite do the job. if your using carbs metro or montego turbo su,s are the easyist ones to use. I did one a long time ago using ford granada 2.8 injection and a turbo from an escort. to much boost broke the crank. try the sports six club some one i think turboed a gt6 if i can help pm me . have a look at [rotex site] they have done some alfas for fiat. I know its not supercharging but mite help with engine mods have alook at this site mite help somemore www.turbo-tr6.info


all the best good luck ken

[Greeks]

Andrew Avis in Queensland has a supercharged PI (or did when I met him). He didn't do it himself but he would be worth contacting:
http://www.triumphowners.com/528

[mikeyb]

Hi,

If you have read some of the other posts youu have probably read some of mine.

I was going to use an Eaton M62 on my car, but i decided all the hassle of making pulleys etc wasn't for me. (so i still have an M62 in the cupboard )

anyway I am going down the "rear end" turbocharging route, I have a KKK turbo desinged for a 1.9 diesel, i'm not going for massive boost, 7psi max, and this turbo should be adequate.

If you can find the back issue of PPC with the rear end turbo'd pug 205, thats what gave me the idea.

I am leaving my engine well alone in terms of compression ratio, as standard it is 8.5:1 which in my opinion is adequate for 6-8 psi.

BEAR IN MIND THE MOSS KIT IS DESIGNED FOR USA SPEC TR6's WITH 7.5:1 compression. You used to be able to get the usa spec heads from Rimmer Bros if you wanted to go down that route.

Anyway I'm rambling here, the easiest way to lower compression if you need to is to find a USA spec TR6 head, this should give you 7.5:1.

Are you using an intercooler? do you have any sort of ignition retard sytem lined up? Boost valve? Wastegate?

I'm a bit of a "blown stuff" buff

Mike

[Steve Knight]

I was led to believe that export USA spec' TR6 heads had different spacings to the exhaust outlets / and manifold. i.e inner 2/3 4/5 closer together.

Maybe its not true; cant see why BL would have wasted production time & money with that.

SK.

[Alec]

Hello SK,

well they did and your guess is asgood as mine as to why?

I found out in a roundabout way when I bought a gasket set from a supplier. Came to fit the manifold gasket and the ports didn't line up with the gasket! I learnt later about the US heads. I believ later imports reverted to UK spec heads?

Alec