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Since the way it was described to us was that the Mahle would definitely need to have the block decked for a true 0 deck, and the Wiseco may need to be decked to get true 0 deck, the shop preferred the Wiseco. But the Wiseco is -8cc whereas the Mahle is -4cc, and the -4cc would make it much easier to get near 12:1-12.5 compression. So I decided to go with the Mahle, and we'll see where we are after it's installed, then deck if necessary to obtain the desired compression.
Last edited by JimMueller; Mar 18, 2019 at 12:42 PM.
Reason: spelling
but to make the power you want a sbe ls3 with gmpp heads would be fine. Really a solid bolt on ls3 would meet your acceleration goals with the right stuff around it
Don't let that $ burn a hole in yo pocket. Sometimes the parts surrounding your engine are more important than the sum of the engine.
Last edited by HioSSilver; Mar 18, 2019 at 12:00 PM.
Mahle gave me two more re-sellers to contact as they cannot sell direct. The re-seller near Miami wanted $995.19 shipped next day delivery and the other re-seller in SD quoted jobber rate, $650 w/o tax/shipping. However, neither could ship to a non-billing address on the first order. Summit also called back to say their price is $675 + shipping, and they will ship to my shop, but while I can pay for next day shipping, they can't guarantee it'll go out today since it drop ships from Mahle. I'll get back with my Mahle rep to see what we can do to ensure they ship today.
For more I think about it, the more we'll just refresh the old heads. I'll need new seals which they say are all the same and they can pickup locally, I might need new intake valves and a valve job. Suggestions on valvespring kit? Will valvespring selection change dependent upon which combination of lifter & rocker arms I use?
Mahle agreed to let me order direct from them and ship to my shop for delivery tomorrow.
Spoke with Joe at Johnson Lifters.
* When setting pre-load in the engine, sometimes the oil pre-installed in the lifter from the factory will seep out, and it's important to have a thin oil in the engine during startup to ensure it gets into the lifters, something like a cheap 30 weight.
* They have people using 20W-50 oil with these lifters
* Axle oiling may reduce oil pressure by 3-5psi
* Excessive lifter bore clearance will also lower oil pressure
* Lifter diameter is .8418-.8422, desired lifter bore clearance is .0015-.0020
* Set pre-load, find 0 lash, then (for aluminum engines) add .0035 to pushrod length
* That should set preload to ~.0020 when hot
* Max valvespring pressures confirmed to work with the lifter is 185 seat, 530 open.
I've asked the shop to measure my lifter bores to confirm compatibility. What's the minimum chamber size on a L92 head before I run into fitment problems with other parts, assuming valve reliefs?
What would be better with an anticipated valve lift of .620 max? Using YT UltraLite 1.8's with a cam shorter lobe lift, or the YT 1.7's with a cam with more lobe lift? I spoke with Derek at TSP and he preferred more lobe lift (because you can use a more aggressive ramp) instead of more ratio lift. But he did express concern that the aluminum rockers need to be monitored every once in awhile, and I'm not crazy about that (just like I'm not crazy about checking lash on an LLSR setup).
Might be worth considering this set of used but just refreshed et of Jesel 1.7's roller rockers that can handle 900 pound spring pressure that one doesn't have to worry about. They are a little harder to set up. Jesel LS 1.7 SS series roller rockers
Might be worth considering this set of used but just refreshed et of Jesel 1.7's roller rockers that can handle 900 pound spring pressure that one doesn't have to worry about. They are a little harder to set up. Jesel LS 1.7 SS series roller rockers
My 91 RS has a set of them
That is a good deal, what's involved in setting them up? A Youtube video looks like it needs taller valve covers? Are they install and forget?
The set of Jesel's in the link are SS 2030 for a hydraulic cam I believe.
Yes, they need valve cover spacers because the rocker is taller. I think the spacers are included with the rockers in the link. My RS has the spacers with the LS1 valve covers. There may be a small section that needs clearance. Aftermarket valve covers look nicer but I like spacers.
Shiney metal band under passenger side valve cover is the Jesel Roller Rocker spacer. Standard LS1 plug wires are long enough. The RS has a set of truck wires on in the picture.
You'll want to confirm but I think this is the instruction set that applies. It shows the general outline in any case.
My friend that built the RS's 383 LS1 said the Jesel's are fiddle prone to get the wipe pattern correct like most other roller rockers. Since they aren't adjustable I believe he used .020 or .050 shims under the rocker stand get the wipe pattern exact.
I've had them on the RS for 11,000 miles and 3.5 years with no issues. As with any part subject to intense racing they probably should be checked yearly or when doing fresh valve springs.
Like all the other roller rockers they do put a little more weight on the nose so better springs are needed.
I received a delayed response from Improved Racing today, and the crank scraper has already shipped. This information is not published on their website nor was it fiven to me when I explicitly listed the f-body oil pan when I spoke with their staff on 3/15 prior to ordering the scraper. I'd really like to use the scraper, but don't want to buy the Holley oil pan and pay a second time for the baffle. Maybe there's some information somewhere else on what needs to be modified on the stock oil pan.
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Yes, the factory oil pan will not clear a 4" stroke. You will have to modify the oil pan or use an aftermarket pan. With the 4th gen F-Body, if you have a stock K-member, you need a low front-clearance oil pan. You can use a Holley oil pan, part number 302-3, which provides the needed clearance and will clear a 4" stroke.
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I meant that if you have the stock K-member, you have to use a low-front clearance pan like the factory 4th Gen F-Body oil pan. However the factory pan will not clear a 4" stroke crank without modification. The Holley 302-3 oil pan will clear most 4" stroke cranks and rods, and should also clear the factory K-member.
It's just a very tight fit to get a 4" stroke in there. Some people with aftermarket K-members can use a normal oil pan because the aftermarket K-member provides more clearance at the front of the oil pan.
So in summary, the 4" stroke will hit the factory pan. The options are:
- Modify factory pan to clear
- Use the Holley 302-3 oil pan, which clears the factory K member and a 4" stroke
- Use an aftermarket K-member that provides more clearance for other pans
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4.125" is a little much with the stock pan. Gets thin up front when you clearance for the stroke. But 4" stroke isn't a problem usually. Just clearance it.
Or are they saying their baffle/scraper for the 4" crank won't clear in the stock pan? If so, why do they make it?
Those are the owners direct words from his email. I'm hoping it is simple to clearance, I just don't want to rush to order a replacement oil pan at the last minute. You could say I'm a bit **** at trying to be proactive.
For realz. So much easier to get in there and work. Worth doing regardless of oil pan.
I went through it too. Went with the holley pan. You need to verify steering gear clearance with IR also.
So if I get the UMI tubular k-member, I can keep the stock oil pan and not modify it and the scraper will work fine? How does the k-member allow more crank clearance inside the oil pan?
So if I get the UMI tubular k-member, I can keep the stock oil pan and not modify it and the scraper will work fine? How does the k-member allow more crank clearance inside the oil pan?
No, but tubular K will clear any pan. I did not say that very clearly. My bad.
So you're saying the steering gear interference is with the Holley pan? How do you increase the clearance if necessary?
There are several holley pans. Mine had interference. Not all do. So before you order - if you order - verify steering gear clearance. IR will know.
I run a burkhartchassis manual gear kit. It's out in front of the balancer so no clearance issues. If you do end up where all have clearance issues, then you know you need to have the pan modified.
Just trying to save you ordering something you cannot use.
I have a Moroso 7qt pan, PN 20140. It clears the stock k-member, steering rack, and the 4.250" stroke crank. I even used my stock full length f-body windage tray. If I were to do it again, I would use the 20141 to make routing the lines for the remote filter easier.
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