When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
@Roger Mabry Roger is that dyno dated in 2004?! have you been holding onto this engine for 15 years lol. Please tell me it was in another car during this time?
Not to mention, who thinks that 400hp is so much power that the car is unable to be handled?
The power to weight ratios on these cars are godawful, even after you shove a healthy engine into it.
If you give a thousand HP engine to an average driver and shove it in an average street car, there really still isn't much to be concerned with.
The car doesn't do stupid things, the people do stupid things because they are having more fun.
Can these cars put all of the torque to the wheels without breaking something?
Depends on what engine you have in it, chances are probably not no.
Does it even matter though? This all comes back to the idea that you are capable of breaking your car.... but I can think of plenty of ways to break my car without putting more torque to the wheels.
Why does everyone care so much about whether they are capable of hitting the theoretical limits of putting down the power the engine is capable of producing.
@icsamerica You have great information to share in most situations, but the way you present it can make you seem like a snide ***** at times.
1) Does anyone think a hot air intake on a forced induction car is a good idea?
No, probably not, and I imagine that he is just as aware of this as you are. Which would mean that he probably has a good reason for doing so.
2) Does anyone else think LSA powers level with such a skinny tire is a good idea? Yes, I think it is a great idea. A street engine on a street tire in a street car will be perfectly fine.
3) Does anyone here think the Jaguar emblem in the engine cover is a Nice touch?
Yeah, I do think it is a nice touch. Would I do it to my car? No. I don't prefer engine covers and adornments. But I am not going to knock Roger for doing what he wants with his car. Don't be an *******.
I never said I had a stock ZZ4 383.. it has a Comp roller cam, 1.6 rockers, Edelbrock 6090 heads and I have the dyno charts showing the performance. You guys really should investigate things before making caustic comments... The engine was speced to make lots of low end torque...it is easy to make HP/torque if you have a clue how a engine actually works.
The stock ZZ4383/425 street engine made 425 HP and 460 # torque but at higher RPMs...Plus it is in a S1 that is lighter, shorter than the later LWB cars.
Just for the doubting Thomas's, here is one of the dyno pages...
That graph confirms EVERYTHING i said... 100% Read on...
Correct me if I'm wrong but If I recall... Depac Dyno's were not the chassis type. That graph is most like from Depac Dyno Cell with ideal conditions.... Dyno headers +20HP, no muffers +15HP, and perhaps a velocity stack +10HP. Corrected too, a perfect 60 degrees, dry air, etc, a perfect 29.92" Hg .... that's sea level... OR is 1000 feet higher. So i'd call that graph WILDLY OPTIMISTIC too.
Experience tells me in a car with street headers, full bendy exhaust, hot, and normal induction, 1000 ft up, it will make 55 HP less. Nice try though. That's the type of dyno graph the engine builder gives you to make you feel good. The date is a bit suspect too and raises quite a few questions. Are you still running 33 Degrees timing in the car hot? I hope not. That engine, installed as a package, spinning a torque converter, trans pump, alternator, water pump, belts, with TBI and a reasonable about of timing will struggle to make 350HP. Sorry, your original point is moot.
I'm sure it's a strong engine non-the-less. Most 383's with comp stuff, and Edlebrock heads are. Changes nothing in my mind, only confirms it, by being a dyno cell with corrected numbers. I'm sure your car drives great but it's no LSA and all the problems at that power level will only increase.
So fact remains, you're not making the power you think you are in the car, 2.88 gears dulls the hit and you can only get wheel hop, cage twist, broken mounts and the other power related IRS problem IF you got the tire. If you don't have the tire, you dont have anything else but wheel spin.
Dont forget to check your hubs for cracks too.
Moreover... for everyone else...It would be prudent to work backwards, tires first, brakes, suspension, drive line, chassis stiffening, THEN THE ENGINE. Guys you're doing it backwards. That's the way, anything else is just clowning around... but that can be entertaining too.
Last edited by icsamerica; 12-18-2019 at 07:27 PM.
The engine was on a engine Dyno, it had my Sanderson headers and my carb (Quadrajet). I currently run 34 degrees total timing. Adjust Hp/torque by 15 percent for at the wheel numbers. No cracks at hubs since 2005 when the engine was installed...or no other broken pieces. Unless you beat these cars to death, you should not have parts problems.
Also the HP and torque quoted on the LSA are engine Dyno numbers as well
Last edited by Roger Mabry; 12-18-2019 at 08:43 PM.
The engine was on a engine Dyno, it had my Sanderson headers and my carb (Quadrajet). I currently run 34 degrees total timing. Adjust Hp/torque by 15 percent for at the wheel numbers. No cracks at hubs since 2005 when the engine was installed...or no other broken pieces. Unless you beat these cars to death, you should not have parts problems.
Also the HP and torque quoted on the LSA are engine Dyno numbers as well
I thought you were running rams horns? Are these the same Sanderson you took off for cracks and now hang on your "wall of shame" and not on the car ? BTW, I've used Sanderson headers on 2 jag projects, slaggy welds but no problems for me. A good tune and reasonable EGT's by virtue proper fuel and timing helps. The set I have now has survived 3 trackdays (road race), in the June heat and years of street and strip use. I guess you just got a bad set.
Last edited by icsamerica; 12-18-2019 at 09:13 PM.
Just as a reference point about hub cracks. I have a Daimler DS420 limousine with the factory 164hp version of the 4.2 and the rear hubs cracked from the weight of the car. I can certainly see how putting much higher levels of power through them would cause them to have a shorter life.
These pics just came in from a customer down in Australia and you might find them interesting. Specifically, the car is 76 XJ6 sedan and the engine is a late LS1 from a 2001 Holden Statesman, which is a sedan version of what we call the Pontiac GTO here. The car is obviously in mid-project here but what is interesting to see is both how far back the engine can sit in the Jag (and still give plenty of access to firewall AC and heater fittings) and also how low (as seen in the front shot).. Couple that with the overall lower weight of the aluminum LS package compared with the stock Jag 6 and you can imagine the benefit as far as balance. Although I have never weighed my LS1 XJ6C (one day I will), I did have my LS1-6 speed XJSC on the scales and it came in at nearly perfect 50-50 distribution, something we know the V12 XJS models wouldn't be close to and I have a feeling neither the 6 cylinder versions. In the side shot you can see the belt tensioner pulley up top- that aligns with the forward-most point of the crank pulley below-basically the very front of the engine. The crank pulley is basically right above the front edge of the front crossmember. Working on the engines here is a snap- you've got plenty of access. And Craigs LSA will like give even more space as his later LS accessory drive is actually closer to the block than this one.
In these pics the cooling package (a modern alum core/plastic tank radiator, matching twin electric fans, and full size parallel flow AC condenser) sits in the stock Jag location. Only the fan set itself sits rearward of the radiator header plate on top (they made a custom one for this car- not really needed as the stock one could have been
used as well)
Yes, I currently ported 2 1/2 inch Ram Horn manifolds that are fully ported. No noises or
cracks and I am sure equal to or better flow than the headers.
Yes, I am currently running ported 2 1/2 inch Ram Horn type manifolds that are fully ported. No noises or
cracks and I am sure equal to or better flow than the headers.
With the EZ-EFI system, all AFR and timing needs are done automatically.
This whole post started about the NEED to reinforce and change things to keep them from breaking. I drive my car hard but it is not raced or abused. Higher HP does not break things by itself...people do.
.
..
Last edited by Roger Mabry; 12-20-2019 at 12:35 PM.
OK... The main surgery is on the cards starting in two days.
Off to the workshop for Engine placement etc, transmission mount will be designed and built as we go along with the tranny connection and driveshaft geometry.
Hopefully she is mainly in place by end of Friday.
Godspeed!
Last edited by Crackerbuzz; 12-30-2019 at 09:07 PM.
Hello all... It has been a very productive two days...
All in all, things went smoothly and were remarkably problem free.
We were expecting major difficulties trying to fit the 6L90E into the tunnel.
There were NO mods required at all and, in fact we used the existing modified rear cross member from the original 1974 coupe. (It had been previously modified to fit a TH400)
We modified the engine mounts supplied to us by Andrew just very slightly, as the sump was not quite clear of the steering rack.
This was in fact my fault as I did not cut a large enough section from the alloy sump pan the first time, otherwise the mounts would have been spot on the money.
It was easier to adjust the mounts than to re-modify the oil pan. The modification of the engine mounts was to simply add a slither of steel plate and relocate the holes which allowed us to shift the engine further backwards by 3/4 of an inch, resulting on a much better clearance of the rack.
The engine has fitted very well, however there will need to be an adjustment of the bonnet sub-frame to allow the bonnet to close. This will be sorted in a few weeks once the plumbing and wiring are completed. The engine did actually sit a little higher than expected, so hopefully this won't be too big an issue. Worst case scenario is we get a very slight bulge formed into the hood where needed, albeit very slightly. (We shall see!)
The clearance in front of the engine is massive! Enough for 5 radiators!
The transmission mount was adjusted and a small plate made to lift the rear angle by approximately 3/8 of an inch. There was no modification required of the tunnel at all. Quite remarkable considering the size of the 6L90E.
The transmission pan does sit lower than standard due to the depth of the casting and will require a skid plate that we will mount off the front cross member at some stage.
12-18-2019, 01:43 PM
