started the jag up today for the first time with the supercharger today. only ran it for a few seconds as i need to re do my radiator hoses. the blower drive belt doesn't like my old hoses and routing witch wasn't anything great to start with. i think i am going to fabricate some metal coolant hoses tomorrow and just attach those with a short piece of rubber on each end. hopefully ill get my first test drive in tomorrow.

 

got things buttoned up today fluids full ect, unfortunately all i could do is putt it around. would make 5lbs of boost at around 30% throttle. goose it and it will hit 10psi in the blink of a eye with the over drive pullys on it. i am going to have to order a larger blower pully before i can run it threw its paces. i had boost in mind when i put this engine together but not 10lbs at half throttle...lol iv got the timing set WAY conservative. at about 25 degrees total timing a good dose of octane booster in the tank. even at 25* total timing the throttle response is amazing. if you goose it 1/4 throttle off the line it will spin the tires. even spun them a little rolling in 2nd one time goosing it. cant wait to get the pulley drive ratio down so i can actually give it some throttle and rpm without the boost going higher than i feel comfortable with.

 

 

yeah, i should re-read my post maybe i had a typo, this style blower would have originally come with a 3 inch top pulley and a 6 inch lower, i got 2 sets of pullys with it, a 6 rib 6 inch bottom pulley and a 2.8" top pulley but the 6 rib crank pulley was damaged in shipping. 10 rib belt the other set witch is on it now is a 10 rib 7 inch bottom pulley and 2.5 inch top pulley (was used on a larger displacement engine)

i ordered a 3 inch and a 3.5 inch top pulley to bring my boost down with the 2.5 inch top pully im hitting 10lbs of boost hardly cracking the throttle open. the 3.5inch top it will be pretty close to the same ratio to the ratio the blower would have had on it from the factory. and the 3 inch should put the blower at 14k blower rpm when the engine is at 6k rpm witch is where my camshaft grind starts to loose efficiency.

using the 10 grove 7 inch pulley and a 3.5 inch top pulley is a better setup than a using a 3 inch top with a 6 inch bottom. should spin the blower about 12k rpms at 6k and should make around 5-6lbs of boost. im thinking the 3 will make more like 7-8 if i did my math correctly so this should give me two usable pulley drive ratio's

 

got the pully's swapped out, running the smaller out of the two pully's that i bought right now, its peeking about 7psi, witch is still a bit much for pump gas on this engine, got some good gas in it so i could get the tune up close still only running 25 degrees of total timing. ill get the boost down to about 5psi for 91 octane pump gas and ill bump the timing up a bit when i get it down to 5psi but i would have had to get a longer belt or re position the tentioner. to get that pulley on there today

but it does good burnouts for distance with the blower....lol on paper this engine should be making about 590hp at 7psi and about 530hp at 5psi

link is a quick video clip

 

here is a video on the install for anyone that's interested.

 

Super cool

 

at least one person here doesn't think i committed a crime against humanity.....lol JK

 

Setting aside the accusations of blasphemy for a moment, I had wondered after cringing at the burnout video, if your next video is going to be a rear IRS rebuild? but really it isn't great for those cage mounts as they can split right off. I think Ron here has some pics of what he did to his Jag to fix that, it was a solid track arm type bar bolted to rear suspension cage and mounted under the back of transmission.

 

i replaced mine just before the v8 swap. i have beat on it pretty hard over the last 2 years and so far so good, i don't expect them to last. the mount bushings really are not to hard to replace, i keep a pretty close eye on them. iv seen the pictures of his set up before. i will probably do something similar in the future. it also would be pretty easy to fabricate some solid cage mounts. but that would surely transfer some more road noise and vibration into the car.

the factory ones fell apart with the stock engine im guessing age has almost as much to due with high failure rates as abuse.

 

I've wondered about solid mounts, might defeat the purpose of independent rear suspension though, or tear a hole in the bodywork with your 500hp+ setup! I agree on the stock parts aging badly, as is the case with old british rubber. SNG Barrat sells uprated hard mounts, which I used on my rebuild, its worth the extra couple bucks.

 

solid mounts would certainly be a trade off, there would almost certainly be more noise and vibration from the road transferred into the car. the irs would still work exactly the same however. i doubt you would rip the mount out of the car, the force applied to the car would still be the same, but it would maybe be possible to get some metal fatigue cracking from a ridged mount it would be easy enough to weld in some spreader plates. if it was a problem. i don't think this would be a good option on a stock car, the downsides would be more tolerable in a performance orientated car vrs a gt car but it would not be my first option.

if you look at the mounts there not very strong against a tension load. when you apply torque to the ground threw the tires its going to want to try to rock the sub frame pushing up on one side and pulling down on the other. the stock arrangement relies on the weight of the vehicle keeping the mounts under a compression force. rons setup works by re directing the torsional load away from the sub frame mounts so they stay under only a compression force. its possible you may be able to simply run a bolt threw the rubber mount tighten it till it touches in a no load situation so its still on rubber under a compression load but if it goes into a tension load the load will be carried by the bolt.

the best solution would be to capture both sides of the mount in steel and rubber so no matter what direction the force is applied the there is a compression load opposite the tension load and your still be rubber mounted. then there would also be a fail safe in case the rubber were to fail.

 

Look at the Aston Martin DB7 rear brace, this setup would also add chassis rigidity especially with your power level.

The other weak point in the rear end is the half shafts, a few XJS's here have twisted half shafts on the dyno. The fix is tubular like in the first few e Types, 2" will fit between the coilovers without modification.

 

i just google searched it looks like they use a very similar irs to the jaguar if not the same, almost looks like one would bolt in place of the factory cross brace in my xjs. but fabricating that brace would not be very hard. i had not really thought of tieing the subframe to a cross brace like that.


i had not really heard of many half shaft failures certainly don't doubt it though. right now i don't have enough traction to put all my power to the ground so that certainly makes it a little easier on parts. trying to launch it on slicks on a prepped surface will certainly be the true test of what is strong enough and what is not.

 

The DB7 was all the XJS floor pans left over

Front and rear subframes are XJS, there are a few differences like brake disks and the rear LCA has a triangular gusset welded in, but everything is interchangeable.

The X brace is very similar to the last of the XJS convertible brace, with the exception the DB7 also fixes to the bottom of the rear subframe where the XJS did not.

 

i like it, i am probably going to duplicate that. not sure if ill just add the mounting points to my existing cross brace or build a new one out of rectangular tube like the db7 one, but that should be a pretty simple mod that will add a lot of strength anyway.

 

I meant to say the mounting points were the same not the x brace.

Anyway post pics when as you go I would be interested to see what you do.

 

Wow. Love to see stuff like this. You picture it in your mind and make it happen. All the while doing it yourself. Mad Max would be proud of you

 

certainly will do, i figured you meant mounting locations not the brace its self.

thank you,

 

did a bit more tinkering and tuning on it today. got my street pully on now, i cant believe how good my math was on selecting the pulley sizes. the bigger pully i intended for normal street driving on pump gas i wanted to make between 4-5 psi of boost witch is exactly what it makes i wanted the drag strip pully to make between 6-7 witch is exactly what it made...lol

iv had a bit of a tuning issue trying to run this 750cfm vacuum secondary carb. basically it has a bit of a lean swing as the secondary's open up never had this issue normally aspirated, in fact i was running the lightest available secondary spring with no issue. basically my theory because the blower is actively creating a artificial vacuum under the carb its creating a good bit more air speed threw the primary's causing the secondary's to come open faster than they normally would and the boosters just are not able to keep up with the rate of opening on the secondary's. iv gotten rid of a lot of that by going to much heavier springs in the secondary's to slow the opening rate. witch makes it drive able, still had pretty much a 2.0 swing in a/f ratio as the secondary's open up. it comes back to where it should be once the secondary's reach wide open it stabilizes. in my initial tune up i kinda worked around this by just making it really fat and rich everywhere so even during the lean swing between when the accelerator pump shot ends till the secondary's reach wide open and stabilize it still stayed an a decent a/f ratio range.

with the tuning setup like that it was pretty bad on fuel, of course a lot of that has to do with my right foot testing out the new found power, but it would burn threw a half tank of fuel pretty darn quick. it was a bit excessively rich everywhere else to try to compensate. i have no idea how bad the fuel millage was but the car was getting about 14mpg before the blower and i would bet i was getting half that.

today after dropping the boost down to a more pump gas friendly 5lbs peek with a bit less airflow demand it was really even more excessively rich so i pulled two jet sizes out of both the primary and secondary's, ended up with a a/f ratio around 14.0-14.2 at steady state cruise at 70mph once you tip into the throttle enough to open the primary power valve it would drop into a nice 12.2 and would run threw the top end once everything stabilized out at 11.9 very happy with those numbers. however this caused my lean swing to go lean enough to cause a stumble and considering you are making power at that point and under boost really not a good place to be leaning out. so i went with a even heavier yet spring in the secondary's so slow there opening even more. to keep the lean stumble at bay although its still swinging into the high 13's to low 14's witch im not really comfortable with. also going so heavy on the secondary springs makes the power come on more like a turbo car than a roots blown car.

i don't have much on hand for tuning accelerator pumps but i suppose i am going to have to order some, really everything on the primary side is working very well. my modification for a boost referenced power valve works flawlessly but the lack an accelerator pump on the secondary side is hurting me, i think my only shot of making this carb work on this application is a big accelerator pump cam and pump with a small nozzle and try to get the longest duration shot that i can and hope that it will carry threw the secondary's opening up. if that doesn't work ill probably have to go to a double pumper witch would really be the right carb for the application anyway.