Home of RedCarDriver's Street Legal Racing Redline modding and screenshots. Other SLRR sites: Virtual Stance Works・GOM-Team. 51 rows SLRR NOOB GUIDE; VS Facebook. The engine is a redesign new that. Mguar wrote: The stock V12 has 3 basic versions. 1971-1980 was the flat head era, 1981-1992 was the HE era (still 5.3) and from 1992 through 1996 Jaguar made 6.0 HE's. 366 cubic inches instead of 326 in the 5.3 that added 40 cubic inches gives another 25 horsepower. The first roughly year and 1/2 of the 6.0 production the crankshafts were forged hardened steel. Later cranks were made from sintered Iron. Stock the fuel injection will flow1200 CFM more than enough to support 450hp. The earlier carbs used prior to 1975 will only flow 800 CFM but that is mostly wasted due to how it's arranged. That is it enters down below the valve cover and is heated prior to it wandering it's way into the engine. The MGBGT autocrosser guy cut off that goose neck and picked up a lot of power. There is even greater potential if you cut open the Fuel injection manifold and weld a plate across it to take 3 Strombergs per side. That's 1200 CFM. (That's for us luddites who don't like the complexity of Fuel rejection). Webers while sexy and a whole lot of eye candy, require dyno work and complete rejetting to run right. Assume about $1000-$1200 for parts. Power gain is right there with the 6 Stromberg mods. Due to the too short intake stack to fit under the stock hood. Whereas almost any other mod requires a computer upgrade. Headers: are wasted on the V12 (except all out designed to match the camshafts equal lengthheaders) Unlike a V8 the exhaust pulses are even and not in conflict. Cam shafts: the stock cam is remarkably good. For all out racing it can be beaten but for street & autocrossing etc. It's great right as it is. Regrinds by ISKY and Crower will add power if combined with higher compression ratios. A gain of 100 horsepower is possible. Port work will add to those numbers. ![]() The stock Valve springs: were reved by the factory to 7800 rpm before they bounced and since the power peak is at 5750 rpm not a restriction. If tired ISKY sells good valve springs cheaper than I've seen Jaguar valve springs priced. The pistons are typically 7.8-1 compression through 1980 (a handfull are 9.0-1 in the earliest XK-Es) Starting in 1981 compression jumped to 11.5-1 However those pistons cannot be used in the earlier flatheads. (1971-1980) What can be done to the later 6.0's is use the earlier 7.8-1 compression pistons suitably relieved for valve clearance on a 6.0 and you'll be right around 13.0-1 compression. Stock the V12 has a 3.543 bore (both 5.3 & 6.0) max safe overbore is 3.681. Which combined with the 6.0 crankshaft yields up 6.47 litres. All other things being equal overbore will yield an additional 25 hp. (plus whatever power improvement using higher compression ratio) In general it's safe to say V12's start near 300 hp. And the 6.0 makes about 25 more. It's pretty safe to assume that with any mod the 6.0 will yield up another 25 hp over the 5.3 there is roughly 15 horsepower more from 9.0-1 compression to 7.8-1 compression another 10hp. At 10.0 & 10 more at each added one point of compression. (those are factory numbers) The cheapest power gain is using a stone stock 5.3 with a pair of turbo's off junkyard salvaged Volvo's/ Saabs. (little T2's) Mmm. So.The grm formula: POWER 1981-1992 V12 Jaaaag Junkyard T2's, two of them Junkyard Intercoolers, two of them Small 45 Amp Alternator Vortex fuel tricky thingy Remote Tank power steering pump What are the gotcha's? Ie the self immolation fuel lines? Known weakpoints? Does this era have some form of GM tranny that can be easily handled or is it a ZF nightmare? Just a quick summary with some follow up questions to perfect my craigslist search. I have actually worked a v-12 jag of some late model vintage. The fuel lines self immolated the car, and my buddy decided he would rewire it and get it running. He did, although I was brought in to change the starter. The jag manual called for pulling 83% of the car apart, I created an 'access port'. For all I know the car still runs today.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. Archives
November 2018
Categories |