I want to get a boss block for my 03 cobra but i have heard of alot of head gasket failures with them. Is there a fix for it? different kind of head gasket to use with it or something? searched but couldnt find anything, any help is appreciated, thanks guys.
BOSS big bore 302 block head gasket fix?
- Thread starter caaron101
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There isn't a actual fix so speak.. Some people have had luck with ARP2000's and tqing them to a higher ftlb.. Still for big boost it'll be in the back of your mind. What makes you want to get a Boss block and add more weight to the front of your car vise going with a teksid block with more compression?
well i have the stock heavy block now so it wouldnt be much more weight than what i have now, but I was thinking about the teksid as well but from everything i have been reading it seems the iron would be better for more boost as im going e85 soon. i have a 2.3 whipple and installing 1 7/8 inch kooks headers and full 3 inch exhaust and comp stage 3 cams in the next couple weeks. shooting for 700 with e85.
Maybe raise this question in the Terminator thread or the 03-04 lot of people in there have tried a lot of things???
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No iron isn't necessarily better. People run 30+psi through both iron and aluminum blocks just fine. The Teksid is the strongest block (with the least false) that Ford has ever made for the 4.6's. 700rwhp is nothing. People push well over 1000rwhp on stock teksid blocks with no issues.. Just saying. This is coming from someone who had a Boss block built engine, and is now doing a teksid built engine.
I want to run a boss block as well so I can run a big cubic inch motor. how much bigger is the deck height on a shelby 5.4. maybe we can run that as a short block?
You can but why? It may make sense for an N/A application, but if its FI its cheaper to add more boost as either block will handle as much power as you want.
If you do run a 5.4 you wont be able to re-use much.
Ask yourself:
What differences exist between a Boss block as opposed to any other mod motor that's been punched out to 3.700" bore as it relates to head gasket failures?
How many Boss block have actually experience head gasket failures? Something tells it occurs more frequently on the internet then it does in reality as this thread is another shiny example of that.
If you plan on running 25+ lbs stay away from a big bore mod motor. If you plan on running pump gas you should have no problems.
I have seen about 4 boss blocks over the past year in the market for sale that all said they had head gasket failures is the only reason I'm cautious about it, and I don't know the difference between that block and the others because iv only had experience with the stock block. I'm just looking for people that have the boss block that have had them for awhile or people that have had them and went to teksid or back to stock block, and what there recomendations are.
We have a new headstud kit for the BOSS block and other High cylinder pressure applications, it is called the MMR 3000 kit and is a new larger stud, the kit includes a TAP (no drilling needed) but we do suggest the block be honed afterwards with a Torque plate (we suggest the new MMR "full deck" torqueplate. It is ideal for sealing 1500HP applications all the way to 3000HP modulars. The kit adds over 3000lbs of ADDITIONAL preload to the cylinder head/gasket.
here is a pic of them installed:
here is a pic of them installed:
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sweet..
We have a new headstud kit for the BOSS block and other High cylinder pressure applications, it is called the MMR 3000 kit and is a new larger stud, the kit includes a TAP (no drilling needed) but we do suggest the block be honed afterwards with a Torque plate (we suggest the new MMR "full deck" torqueplate. It is ideal for sealing 1500HP applications all the way to 3000HP modulars. The kit adds over 3000lbs of ADDITIONAL preload to the cylinder head/gasket.
here is a pic of them installed:
What is the max boost you can safely run thru the 5.8?
We are currently running 50lbs through the race team 5.8's such as the one pictured above. We have had ZERO head gasket failures since switching to the new MMR studs - they are really stout and the feel as they are torqued is very confidence inspiring compared to the spongy feeling ARP 2000 or L19's which we were using prior to these.
You mean I can buy a 5.8 block off the shelf from Ford and boost it to 50 lbs?
Since you stated there is no drilling involved with installing the these studs I am assuming your supplying a bottom tap allowing the studs to capture more threads. Is that correct? What are you torqueing the studs to both in aluminum and iron?
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Jesus those studs are huge ahahahaha!! Good job MMR for hopefully making a fix to the sealing issue.
You mean I can buy a 5.8 block off the shelf from Ford and boost it to 50 lbs?
Since you stated there is no drilling involved with installing the these studs I am assuming your supplying a bottom tap allowing the studs to capture more threads. Is that correct? What are you torqueing the studs to both in aluminum and iron?
id like to know the same.
damn, those studs are monstrous.
You mean I can buy a 5.8 block off the shelf from Ford and boost it to 50 lbs?
Not quite what we meant, the rods are the weak link, we wouldnt want to run them much beyond 13-15lbs
Correct, and in regards to torque they are 130lbs in both steel and alloy blocks vs the 85-90 lbs of the ARP head studs.
Getting an engine to withstand 50 lbs of boost where they normally wouldn't take past 15 lbs is impressive. I think Ford pushing out the mod motor to 5.8 is a "bridge too far". Not many of the 13/14 GT500 seem to boost their engines to the level 03/04 and 07-12 GT500 guys have ............ than again, "like it really needs it!"
Wow, 130 ft lbs on the head studs. That's pretty huge. At that level I start to worry about the threads tapped into the block rather than the studs themselves especially in aluminum. I am planning on torqueing the bare Boss block to 110 which and check the line bore and bearings saddles and lower bore for distortion having all those studs buried deep in the block. Campaigning a race car and building engines I am sure this is something you have already checked. Any observation with regard to the effects of using such high torque values on the squareness of the block? At 50 psi something tells me just holding the engine together might take priority LOL
Correct, the additional load does distort the cylinder slightly, this is why we suggest honing them with a torque plate after installation. The threads are not a issue, we have purposely installed a torque plate onto both a cast Iron and Alloy block and torqued them beyond 150ft lbs without any problem.
Badass03svt has a built 10:7.1CR aluminum teksid and a 4.0 whipple now. His is a STD. bore block. Those aluminum block can handle a lot of power if built correct.
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