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T.H.O.R. VS Spectre

Are you saying you intend to make your own for sale? Is that why you're offering different colors and giving a price?

What post are your responding to?
 
What post are your responding to?
You know what post I'm responding to, you already responded to me. You said you can make them either blue or black and gave a price for what they would cost. Sounds like an offer to build for sale and that is frowned upon unless you are a vendor.
 
At siliconeintakes the silicone comes in red, blue and black depending on some of the sizes, and the cost will only be about $100 for all the parts. If you have any issues you can PM me.
 
engine_equations_air_flow_rate.png



This is the basic equation used to determine the cfm of a 4 stroke engine.


Thus,
243CID x 5200RPM x 0.8 / 3456 = 292.5cfm for a normally aspirated engine. If the VE is replaced with 1.8 to represent Forced Induction, the resulting value is 658.1cfm. Both at the Rev Limiter.


At a more reasonable 3,000PRM the CFM is 379.6 with forced induction and 168.7 for a normally aspirated engine.


With Forced Induction, the limitation of the Spectre filter is reached (theoretically, of course) at 3,550RPM.

Throttle Body Flow rates.

The formula...

sldemo_engine_eq95017.png


Where:
sldemo_engine_eq80621.png

sldemo_engine_eq70243.png

sldemo_engine_eq97372.png

sldemo_engine_eq95712.png

sldemo_engine_eq75417.png

sldemo_engine_eq94555.png

sldemo_engine_eq87293.png

sldemo_engine_eq27685.png

sldemo_engine_eq86299.png


Engine Flow rate calculator:
http://www.mk5cortinaestate.co.uk/calculator3.php

Using this calculator with 8lbs of boost yielded a 567cfm at 5,200rpm (378hp) and 327cfm at 3,000rpm (218hp). All are theoretical values.

Data from F&B:
62mm TB = 600cfm
68mm TB = 700cfm
70mm TB = 780cfm.

The 70mm TB is available by request. It is not listed on the web site as they make them for 505 Performance to go into the 5.0L strokers.

They recommend that the TB be sized 20% above calculated value. They also say that you need to be at atmospheric pressure at WOT. Anything less than atmospheric indicates a TB that is undersized.

The other point that F&B made was the intake manifold. The hole in the manifold must be matched to the TB or you have negated much of the benefit. I know I had to open up the 99+ intake I used on my 4.7L stroker (2001) to accept the 65mm TB from the 4.7 V-8.

Two calculators, two different engine flow rates. This is due the the VE figure I used for the Forced Induction. The higher the boost the higher the VE.
 
My Volant CAI is about 3.5" necked down to 3" at the TB thru a 62mmTB. It sits up front with an open element and a half splash shield. It is sucking all that hot air that I measured with my 'under hood temp testing'. I didn't measure right at the element but when I put the IAT sensor in the volant plastic tubing, it read 5-10 degrees hotter than ambient even at cruise.

My bigger S/C project started today. Few humps, need a fuel line seperator tool and then the old is off. Looking at the Intake air- the biggest into the cowl is 3" flange adapter then to a 3" to 4" 45* silicone, to a length of 4" polished or painted tube with the air filter inside it, to a 4" to 3" 90* silicone , to the 62mmTB.

So where is the restriction? 3" at the cowl and the 62mmTB. I would go with the 70mm TB but I am sure the tip in throttle response would be too touchy. But that 70mm would sure allow the S/C to inhale cool air.

Spectre says that the 4" will flow 600CFM (i mistakenly previously posted 650CFM). This should be all in the right ballpark.
 
The Gent I spoke with at F&B as I was posting...

Said that with the Sprintex compressor (.94L/rev) and a 5200rpm red line, a 600cfm TB would be a minimum. His recommendation was the 70mm. The cost of the TB is the same be it the 62mm or the 70mm at $375.00 + shipping. Shipping to 80918 is $12.00 so they do not "upcharge" the shipping with bogus "handling" charges.

F&B do a ton of work with Kenne Bell and their TB is included in the KB kit. So, they actually know, from dyno time spent, what works. Very good conversation. This is what I do, I ask those with the most knowledge/experience and take the advice offered. Standard Engineering Practice.

Thing here is that it is that the engine is an air pump and all of the components needs be matched to get the best results. And it all starts at the air cleaner.

According to F&B, the stock airbox on the early Rubicons were a joy to behold inre air flow once the sound baffles were removed. The XJ, not so much... The flex coupling with the expansion joint creates turbulance in the air flow impeading the total flow. OK for a stock motor, not so for a modded one.

Marty, you may run into a clearance issue at the TB with the 3"-4" 90* adapter as there is only about 3/4" between the stock 90 and the hood. I had to trim the stock 90* to clear my drip pans which are ~1/2" from the hood.
 
Yeah, learned about clearance yesterday. The S/C raised and moves rearward the TB. Now my volant CAI will not fit. I have to change it a bit.

The 3" TB that I measured was the TB I had laying around off my F150, I thought it was the Jeeps. Now I will need a 2 1/2 or 2 3/4" to 3" 90 elbow.

1 change effect 3 things down the line. That must be Murphy's cousin's Law.
 
Marty, I will not steer you, or anyone else for that matter, down a bad path.

I have the same clearance issues as well and need a larger TB to boot. Sprintex is just plain wrong about so many things... My system is choked by the air tube leading from the air cleaner to the TB. The issue with resolving it is clearance. The 93 YJ I supercharged was a breeze to do as it has tons of room to work in.

What we all have to keep in mind is that the XJ was designed to take the 2.5L 4 banger or the 2.8L V-6. The 4.0L was shoe horned into place much as a Hot Rodder would shove a large engine into a small space. Space is at a premium as a direct result.
 
I anxious to see the results!
 
For anyone who is interested, I got my Spectre kit in today and it came with both the plain rubber hose as well as the stainless braided rubber hose. I guess Spectre realized that we want the choice!
 
For anyone who is interested, I got my Spectre kit in today and it came with both the plain rubber hose as well as the stainless braided rubber hose. I guess Spectre realized that we want the choice!

That's good to hear. I finally got my SS hose about a week ago f Spectre & it was about 2" short to actually use... so I transfered over the SS sleeve to my rubber hose (albeit still being short) but its mostly there & I now have the 'cool' SS clamps.
 
Has anyone or can anyone check the IAT with their OBD scan tools to see what it is with the Spectre intake? I was wondering what the actual measured temp difference is between stock and Spectre. I know that it seems like it would be a cooler IAT with the Spectre but I would like to see hard data. A back to back test would be best.
 
Hello all,

Long time wrencher, first time XJ'r. Im in SW Florida right next to the Everglades. I NEED a snorkel, especially during the rainy season. I want a real snorkle like the ARBs or Safarilands but I also want to delete the stock air box. I DO NOT want an in cowl snorkel. I want to run a dual battery but don't want it inside the cab. It's my DD so I need it to be solid and look decent? Any help would be greatly appreciated!!!! Also, this is my first XJ forum.....be gentle.:confused:



1996 XJ Country 4.0, AW4, MP231, 3in Rough Country Lift, 31in Sailun Terramax on Crager Soft15x8's​
 
Do these intake systems work with bored throttle bodies??
 
Hello all,

Long time wrencher, first time XJ'r. Im in SW Florida right next to the Everglades. I NEED a snorkel, especially during the rainy season. I want a real snorkle like the ARBs or Safarilands but I also want to delete the stock air box. I DO NOT want an in cowl snorkel. I want to run a dual battery but don't want it inside the cab. It's my DD so I need it to be solid and look decent? Any help would be greatly appreciated!!!! Also, this is my first XJ forum.....be gentle.:confused:



1996 XJ Country 4.0, AW4, MP231, 3in Rough Country Lift, 31in Sailun Terramax on Crager Soft15x8's​

Sounds to me like you'll he stuck having to fabricate something to meet your needs. All snorkel kits retain the factory air box. Although the only reason you would need a real snorkel is if the water is higher than the windshield. If thats the case you shouldn't be doing that in a daily driver in my opinion. The two kits mentioned in this thread will get rid of the factory air box and run the filter either in the cowl space or inline in the tubing. I have the thor and it works well. The only time water would be an issue is if water was cresting the hood. If that were to happen I would definitely have bigger issues as the jeep is not a submarine. Im sure something could be done with an inline filter then connect to a true snorkel kit but your paying double so keep that in mind. If you dont "NEED" a true snorkel dont get one. Plenty of people do water crossings with the stock airbox and are fine. As long as the water doesn't get up to the headlights your good. So you have to evaluate how deep you want to go with a daily driver.

Hope this helps
 
Thanks a lot! I'm just afraid of the ones like yours because in a "nose dive" where water would wash over the hood but not submerge. Also in the rainy season we will get HEAVY downpours. How do you feel yours would do in these types of situations? Do you feel your cowl would drain properly?
 
It would take a serious amount of water at the windshield to overwhelm the space in the cowl. There is drainage also for the cowl area on each side. The opening on the cowl is on the driver side and the filter/air inlet for these kits is on the passenger side. If its just a good slash at the cowl level you should be fine. Again it would really take a lot of water like submerging the cowl to cause worry. Which at that point just shut the motor off quickly as you have much worse issues at hand.
 
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