Hi Barry AFAIK the standard GT6 cam can be replaced with one from an early 2.5 PI saloon (Stanpart no. 308778). I'm not sure if this cam will fit GT6 Mk1 engines or by how much it will increase power. I've also heard that a 2500 saloon crank and pistons can be fitted. Anyone any ideas or comments?
>From what I've read and heard there are various other (sometimes contradicting one another) opinions, theories and ideas on getting more power from a GT6, but herewith some interesting alternatives: 1) Fit a 6-3-1 exhaust. It will apparently boost power throughout the rev range. ( Apparently one of the best improvements to make). Or keep the standard cast iron exhaust as it apparently provides decent mid -range power and torque. 6-2-1 exhausts apparently don't work very well in the mid-range. The True/false ? Some articles differ and advise to use 6-2-1 exhausts. Anyone any ideas or comments ? 2) Replace standard cylinder head with one from a post May 1975 2000/2500 saloon (Stanpart no. 219016). I'm not sure if this head will fit GT6 Mk1 engines. Anyone any ideas or comments ? 3) Keep the twin Stromberg 150 CD carburettors and fit K&N free-flow air filters (apparently torque will be lost with anything bigger and SU HS6 carbs are apparently only good a 2500 six cylinder engine). Some articles differ and advise to use SU HS6 carbs. Anyone any ideas or comments ? 4) Replace carbs and fit fuel injection from a 2.5 PI saloon (recalibrated to work on a 2000/GT6 1998 CC engine). Apparently a 2000 PI / GT6 PI produces approx the same BHP as a 2.5 PI, but slightly less torque. However a 2000 PI / GT6 PI will rev past 6000 whereas a 2.5 PI tends to destroy itself. I'm not certain exactly which parts are needed for such a conversion or if it will only work with GT6 Mk2/Mk3 engines. Anyone any ideas or comments ? 5)Replace the entire engine with one from a 2500 saloon / TR6 (carb) or better still replace it with one from a 2.5 PI saloon ( TR6 PI). A few other ideas to consider: 1) Use a TR4 - TR6 or 2000/2500/2.5 PI saloon gearbox instead of the Vitesse/GT6 gearbox. I have been advised that the Vitesse/GT6 gearboxes are weak, prone to failure and troublesome. It WILL apparently fail if you put more than standard torque through it or drive in a 'spirited' fashion. It will not last with any performance increases. True/false ? Anyone any ideas or comments ? 2) Use a 2L Vitesse/GT6 3.89:1 (if o/d fitted) / 3.27:1 (if no o/d fitted) or custom (3.63:1) differential instead of the Herald/Spitfire 4.11:1 differential. I have been advised that the Herald/Spitfire 4.11:1 differential provides the wrong gearing, that it is also too weak and will fail if used with a 2L GT6 engine. 3.89:1 is a good diff ratio, but apparently 3.63:1 is "the best" diff ratio to use with the 2L GT6 engine and saloon o/d gearbox (possibly even with the standard Vitesse/GT6 o/d gearbox). Unfortunately I have no idea where one could obtain such a 3.63:1 differential, but the guts from a TR7 four speed diff is 3.63:1 and could possibly be transplanted into a Vitesse/GT6 diff casing. Anyone any ideas or comments ? 3) Fit a camber compensator to keep the rear suspension stable. Joe Curry [EMAIL PROTECTED] or [EMAIL PROTECTED] is making and selling such a device. Not too expensive if you live in the USA and a worthwhile investment from what I've read. Unfortunately there's a big pond between SA and the USA, which has forced me to look at making my own camber compensator device using the bottom leave from an old Herald leave spring. 4) Fit an oil cooler. Apparently a necessity to protect a GT6 engine. HTH Chris de Wet . PO Box 472 , Ifafi , 0260 , South Africa . My Spitfire6 project: Spitfire(Mk2) body, GT6(Mk1) bonnet & doors, GT6(Mk1) chassis/brakes/suspension, GT 6 (Mk 1) engine, 2000 Saloon gearbox with overdrive and Vitesse 3.89 differential. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Friday, 24 October, 2003 06:00 To: [EMAIL PROTECTED]; [EMAIL PROTECTED] Subject: GT6 power increases - I was just thinking with the discussion of TR6 (250) power increases (the usual 150 hp) which basically gets a big increase from the fuel inject cam grind but since the GT6 uses the same cam could one realistically expect 130 hp if one were to install it in a GT6? Of course the usual other TR6 mods apply here as well- Sounds intriguing "This e-mail is sent in terms of the following policy/disclaimer. Click on this link http://www.sapo.co.za/mail_disclaimer.htm to read full disclaimer." *** http://www.team.net/the-local *** *** unsubscribe/change address requests to [EMAIL PROTECTED] or try *** http://www.team.net/cgi-bin/majorcool *** http://www.team.net/mailman/listinfo *** Archives at http://www.team.net/archive *** Edit your replies!
