Sprintex Supercharger hits 12 pounds Boost!!

[CobraMarty]

Tuned for 11.7-12.0 AFR, not overly rich but safe. Again thanks for the heads up on detonation. 120-140 IATs is much more forgiving than 200-250+ temps.

We did originally tune with a knock sensor, in, fact 2 different ones.

It seems that 12.5 pounds of boost on a 160,000+ mile original head gasket is the limit regardless of good tune. Others have noted than in the past also. MLS head gasket and new properly torqued head bolts and colder heat range plugs and less than 12 pounds boost (closer to 8 pounds with the bigger S/C pulley) with the ported big valve head will work just fine. Again, time and dyno will tell.

 

[sidewaysstarion]

That's what you need to listen for, and yes I shot that video over 4 years ago.

 

[O-Gauge Steamer]

Tuned for 11.7-12.0 AFR, not overly rich but safe. Again thanks for the heads up on detonation. 120-140 IATs is much more forgiving than 200-250+ temps.

We did originally tune with a knock sensor, in, fact 2 different ones.

It seems that 12.5 pounds of boost on a 160,000+ mile original head gasket is the limit regardless of good tune. Others have noted than in the past also. MLS head gasket and new properly torqued head bolts and colder heat range plugs and less than 12 pounds boost (closer to 8 pounds with the bigger S/C pulley) with the ported big valve head will work just fine. Again, time and dyno will tell.

Personally, I think having the AFR in the high 11 to low 12 is a problem. I run 14.5+/- with the exception of under acceleration where it drops down into the 13 range. Just kept pulling timing out.

Works fine and, IMO, the plugs may last longer as they are not getting fouled by fuel...

Mayhap you can answer this question:
How is it you have the mixture that rich without getting CELs? I can force CELs by altering the fuel map in my F/IC while still maintaining the stoichiometric value for gasoline. When either the Short Term or Long Term Fuel Trims get out of their comfort window, the PCM will toss out codes. I can force it both ways. The PCM can and will report "bank one mixture too___" where the "___" is either rich or lean depending on which way the fuel was driven. My PCM is operating with a 5% Short Term and 3% Long Term Fuel Trims. Which is close to stock...

The PCM wants to maintain the 14.7 AFR by design, have you eliminated the PCM?

 

[bpas328xii]

Mayhap you can answer this question:
How is it you have the mixture that rich without getting CELs? I can force CELs by altering the fuel map in my F/IC while still maintaining the stoichiometric value for gasoline. When either the Short Term or Long Term Fuel Trims get out of their comfort window, the PCM will toss out codes. I can force it both ways. The PCM can and will report "bank one mixture too___" where the "___" is either rich or lean depending on which way the fuel was driven. My PCM is operating with a 5% Short Term and 3% Long Term Fuel Trims. Which is close to stock...

The PCM wants to maintain the 14.7 AFR by design, have you eliminated the PCM?

Still have OEM ECU. MAP sensor is routed to boost. As soon as it hits 0psi vacuum, the OEM ECU instantly snaps into open loop. I can dump as much fuel as I want without getting a CEL because the ECU is not monitoring the O2 sensor when in open loop. Fuel trims are stock (zero or near zero).

 

[CobraMarty]

The 11.7-12.0 AFR is when under boost. Out of boost it is stock ECU and stock AFRs 14.7.

 

[Talyn]

We are going back to the larger pulley and 8-8.5 pounds boost b/c the better flowing head should fill the cylinders better and increase cylinder pressures.

Where is this better flowing head?

 

[Alexia]

Where is this better flowing head?

Perhaps the one from Clegg?
http://www.cleggengine.com/jeep-4-0l-stage-3-ported-head-w-oversized-valves.html

Also this one from Odessa.
http://www.ebay.com/itm/NEW-JEEP-CH...iter_Display:4.0L&hash=item2578bf21d3&vxp=mtr

 

[CobraMarty]

Or here from 505 Performance.
http://www.shop.505performance.com/product.sc?productId=307&categoryId=41

 

[O-Gauge Steamer]

Looks to me like the Odessa head is using the same size valves that were in the Patriot Performance Aluminium version that is no longer available. i.e. 2.02" and 1.62" Both of the heads that Alexia posted appear very good indeed. I can tell you that big valves on a Stroker make a difference. Leastways, it did on the 4.7 I built way back when...

On the other hand, the 505 head... At least from the photos that have been posted, it looks to be a disaster.

Who sells a "pre-rusted" cylinder head?

Had it shown up on my door step, I would have sent it back and demanded a refund. IMO, it should not be installed. Once bolted in, no recourse will be available.

Talyn, calling this head a "boat anchor" is an insult to boat anchors. They, at least, are functional...

 

[CobraMarty]

You can take it up with 505.

 

[sidewaysstarion]

Boat anchor? It does flow the mumbers. What does your DIY port and polish flow?

You mean this "505 Performance race ported big valve head"?

Looks like they gave a monkey a die grinder. I wouldn't doubt if it flows worse than stock.

Interestingly you deleted most of those images from photobucket.

your honor, I rest my case.

 

[CobraMarty]

ArmChair internet head porters, So how does your DIY 'porting' do on the flow bench? What? You didn't flow it? How do you know that all your labor improved on the stock head flow without actually flowing it on a bench? It looks prettier, so it flows better? Low lift numbers better? Don't know?

See you at the flow bench or dyno.

 

[Talyn]

You can take it up with 505.

Its not my POS head. If you are too ignorant to see the mess they made of that head just by the intake valve job then you deserve it. Any one that has an inkling of knowledge of a valve jobs (never mind the "port" work) can tell that that head is junk.

ArmChair internet head porters, So how does your DIY 'porting' do on the flow bench? What? You didn't flow it? How do you know that all your labor improved on the stock head flow without actually flowing it on a bench? It looks prettier, so it flows better? Low lift numbers better? Don't know?

See you at the flow bench or dyno.

It doesn't have to be pretty. Polished intake ports don't necessarily flow better than a rough port. But thats not the point, that work is plain crap.

 

[sidewaysstarion]

ArmChair internet head porters, So how does your DIY 'porting' do on the flow bench? What? You didn't flow it? How do you know that all your labor improved on the stock head flow without actually flowing it on a bench? It looks prettier, so it flows better? Low lift numbers better? Don't know?

See you at the flow bench or dyno.

http://www.streetfire.net/video/this-is-the-video-of-qusetsis-500-hp-starion_41564.htm

Because it held the record for the highest horsepower G54b motor for close to 3 years? The head never saw a flow bench either.

 

[Bryan C.]

I cleaned this thread up. Any further drama will result in infractions and your posts will be deleted.

 

[Bryan C.]

Thread is open. Make your point and move on.

 

[CobraMarty]

Back up and running fine. Left the smaller 2 1/8" (54mm) pulley. AFR and timing right where we want them and no knock or detonation. Having minor radiator issues, time for a CSF 3 row.

 

[CobraMarty]

And yes there seems to be more power off boost and in boost. Will dyno soon after getting the radiator replaced and the smashed/cracked downpipe from the last Rausch Creek adventure fixed with a 2.5" downpipe and new high flow 2.5" cat.

 

[bpas328xii]

Head is on. Jeep runs and goes into boost. I have no complaints about the 505 head.