Do domed KYB 399’s interfere with 302 cast heads?

[waldune]

Debating between 399’s and 167’s, nothing is getting decked just cleaned and built in the garage, I’ve had great experience with 167’s but I believe with the right choice of cam as long as the 399’s don’t interfere with the 302’s I could run premium still and not get detonation.

On the flip side, do you think it’s better to get 302’s and 0 deck pistons or get the domed 399’s on the stock 68cc heads…or ultimately the pop ups and 302s. Using a thicker composite style head gasket, with the flat tops I’d use a shim type thinner gasket .32 squished is a common size I can find and some sits I can get .26 squished for advertised as 318/273 gaskets so I think it’s the 3.91 bore size but nowhere seems to say. If anyone knows the best head gaskets to use that have the proper size combustion ring please tell me and I’ll pick parts based on the thickness of that gasket because if they turn up as 318/360 head gaskets I’ll lose compression gains. Static with the domed pistons is high at 10.8 ish to 1. I think depending on the cam with the domes and 302’s I could run on pump gas. However a lot more goes into it than that static number including if I can make use of that quench area on the heads. Trying to find late 920s with the smaller valves but also closed chamber, great for port velocity and in the build I’m thinking of theyd be perfect But finding a decent set is a pain. Anyway

TLDR: will KYB 399’s interfere with 302 casting heads, if yes is it better to have 302s and flat top KYB 167’s or stock heads and domed 399’s? It’s a street engine but not a daily driver, it is meant to be a bit rowdy but drivable.

 

[racerdan80]

399’s with 360 heads would be my suggestion if you have those heads available. More flow, compression could be in the mid 9’s depending on chamber volume.

 

[racerdan80]

Use the search function and see who has used 399’s. The dome style may need to be shaved for clearance of the closed section of the 302 chamber. The 340/360 open chamber will clear just fine unless they’ve been milled down to nothing.

 

[AJ/FormS]

IMHO,
you need to include your cam in the equation, cuz the ICA is gonna affect the Cylinder pressure quite a bit. Or viceversa, the Ica will require a certain window of Scr to achieve what you're going for.
On the Street;
Scr isn't necessarily what yur after.
Pressure is the thing, and the Ica is gonna play a big part in that.
Scr in this case, is just a means to an end.
If yur gonna run iron heads, you can quickly get into a bad situation. Especially with open chambers.

I run a 360, so it's a little bit different. But with closed-chamber alloys I can and have run 195psi, and if yur running an automatic trans, with a low stall, and you need bottom end, I can tell you that 195psi is killer strong. Typically, you cannot run much over 165psi with Iron heads and best pumpgas. Whereas I run nothing but 87E10.

If you intend to walk that hi-pressure line, with a 318; everything has to be just right, and everything has to be well thought out, including the chassis, the weight, the gearing, and the stall.
Usually, it is just easier to stall it up, and not lose sleep over the lower pressure.

Furthermore;
If you have a manual trans, you don't have the choice of stall, and many many times you are gonna find your engine at too low an rpm, where, with too much pressure, she will detonate; and to eliminate that you will have to sacrifice Ignition Timing, and when you do, away goes the power. In this case less Scr would/could have been better. Walking the line with a manual trans takes extra caution when a manual trans or especially when hi-way gears are involved.

Without knowing any of these other factors IDK how anyone can answer your questions; I certainly cannot.

One thing that is almost a given, is this; on the street; Flat tops are usually best as is a tight Quench. I have always run from .028 to .032, with alloy heads and hypereutectics, with no issues.
In a budget 318, where no machining is allowed, I'd likely run a Quench-pad piston, and closed chambers, but it really depends on the cam.
What I would not do is run less than 160 psi. What I'd like to run is 185 to 195psi, with alloy heads; but that's a stretch for a typical street cam with an Ica of say 61 to 66 degrees.

The thing is, with the wrong street gears/stall, there's no percentage in that either. Low-compression 318s on a budget are just hard.

Here's an example; say the cam you pick will have an Ica around 63 degrees. and say you are at 500ft elevation. To get to 160psi, the compression ratio wants to be, about 9.8 .
But to get to 185psi will need 11.1Scr. But to run that pressure, on the street with pump gas and full timing without some type of anti-knock, you would need alloy heads, and probably a tight quench.
However with a smaller cam even just one size say an Ica of 59*, Your pressures will jump to 164 and 193..
164 will require best octane gas. 193 may not run WOT on 87 gas.

So, in this case if 160psi was not enough for you at 2200 stall, perhaps 2800 would be a better solution, and/or, more rear gear, and/or less weight.

Sooner or later, you might conclude that you need 4.30gears, which then leads to an overdrive, which then runs well at 155 psi, and maybe she'll be able to run 87 gas.

It's all in the combo....... IMHO

 

[273]

399 = open chamber, 167 = closed chamber, not saying it's impossible to go the other way around but that's basically what there designed for especially if you want quench, I imagine it would take more machine work to get the right quench out of the 399 then the 167.

Why go to all the trouble to run 167 but not mill the little bit that's needed to zero deck ?

How much power your looking to build will tell what heads to run, cam will tell you want cr to run and those two things will tell you what pistons to run, don't forget about balancing.

Unported 273/318 heads equal around 300 hp with reasonable cr and cam, 360 heads mid high 300's and magnum heads 400 ish.

With porting and or aftermarket there's many ways you can go.

 

[RustyRatRod]

The 399 is a quench dome that's meant to be milled to achieve optimum quench in the heads they are used with. So no, AS IS, I would imagine the domes will hit the quench pad of the 302s. But the domes can be milled to make some really nice quench. Call United Engine and they can tell you more.

 

[RustyRatRod]

IMHO,
you need to include your cam in the equation, cuz the ICA is gonna affect the Cylinder pressure quite a bit. Or viceversa, the Ica will require a certain window of Scr to achieve what you're going for.
On the Street;
Scr isn't necessarily what yur after.
Pressure is the thing, and the Ica is gonna play a big part in that.
Scr in this case, is just a means to an end.
If yur gonna run iron heads, you can quickly get into a bad situation. Especially with open chambers.

I run a 360, so it's a little bit different. But with closed-chamber alloys I can and have run 195psi, and if yur running an automatic trans, with a low stall, and you need bottom end, I can tell you that 195psi is killer strong. Typically, you cannot run much over 165psi with Iron heads and best pumpgas. Whereas I run nothing but 87E10.

If you intend to walk that hi-pressure line, with a 318; everything has to be just right, and everything has to be well thought out, including the chassis, the weight, the gearing, and the stall.
Usually, it is just easier to stall it up, and not lose sleep over the lower pressure.

Furthermore;
If you have a manual trans, you don't have the choice of stall, and many many times you are gonna find your engine at too low an rpm, where, with too much pressure, she will detonate; and to eliminate that you will have to sacrifice Ignition Timing, and when you do, away goes the power. In this case less Scr would/could have been better. Walking the line with a manual trans takes extra caution when a manual trans or especially when hi-way gears are involved.

Without knowing any of these other factors IDK how anyone can answer your questions; I certainly cannot.

One thing that is almost a given, is this; on the street; Flat tops are usually best as is a tight Quench. I have always run from .028 to .032, with alloy heads and hypereutectics, with no issues.
In a budget 318, where no machining is allowed, I'd likely run a Quench-pad piston, and closed chambers, but it really depends on the cam.
What I would not do is run less than 160 psi. What I'd like to run is 185 to 195psi, with alloy heads; but that's a stretch for a typical street cam with an Ica of say 61 to 66 degrees.

The thing is, with the wrong street gears/stall, there's no percentage in that either. Low-compression 318s on a budget are just hard.

Here's an example; say the cam you pick will have an Ica around 63 degrees. and say you are at 500ft elevation. To get to 160psi, the compression ratio wants to be, about 9.8 .
But to get to 185psi will need 11.1Scr. But to run that pressure, on the street with pump gas and full timing without some type of anti-knock, you would need alloy heads, and probably a tight quench.
However with a smaller cam even just one size say an Ica of 59*, Your pressures will jump to 164 and 193..
164 will require best octane gas. 193 may not run WOT on 87 gas.

So, in this case if 160psi was not enough for you at 2200 stall, perhaps 2800 would be a better solution, and/or, more rear gear, and/or less weight.

Sooner or later, you might conclude that you need 4.30gears, which then leads to an overdrive, which then runs well at 155 psi, and maybe she'll be able to run 87 gas.

It's all in the combo....... IMHO

What the farkin FARK did that response have to do with KB399 pistons? Just incredible.

 

[273]

The 399 have a compression height of 1.81" and a dome height of 0.140"
The 167 have a compression height of 1.81"

Edit

 

[waldune]

399’s with 360 heads would be my suggestion if you have those heads available. More flow, compression could be in the mid 9’s depending on chamber volume.

IMHO,
you need to include your cam in the equation, cuz the ICA is gonna affect the Cylinder pressure quite a bit. Or viceversa, the Ica will require a certain window of Scr to achieve what you're going for.
On the Street;
Scr isn't necessarily what yur after.
Pressure is the thing, and the Ica is gonna play a big part in that.
Scr in this case, is just a means to an end.
If yur gonna run iron heads, you can quickly get into a bad situation. Especially with open chambers.

I run a 360, so it's a little bit different. But with closed-chamber alloys I can and have run 195psi, and if yur running an automatic trans, with a low stall, and you need bottom end, I can tell you that 195psi is killer strong. Typically, you cannot run much over 165psi with Iron heads and best pumpgas. Whereas I run nothing but 87E10.

If you intend to walk that hi-pressure line, with a 318; everything has to be just right, and everything has to be well thought out, including the chassis, the weight, the gearing, and the stall.
Usually, it is just easier to stall it up, and not lose sleep over the lower pressure.

Furthermore;
If you have a manual trans, you don't have the choice of stall, and many many times you are gonna find your engine at too low an rpm, where, with too much pressure, she will detonate; and to eliminate that you will have to sacrifice Ignition Timing, and when you do, away goes the power. In this case less Scr would/could have been better. Walking the line with a manual trans takes extra caution when a manual trans or especially when hi-way gears are involved.

Without knowing any of these other factors IDK how anyone can answer your questions; I certainly cannot.

One thing that is almost a given, is this; on the street; Flat tops are usually best as is a tight Quench. I have always run from .028 to .032, with alloy heads and hypereutectics, with no issues.
In a budget 318, where no machining is allowed, I'd likely run a Quench-pad piston, and closed chambers, but it really depends on the cam.
What I would not do is run less than 160 psi. What I'd like to run is 185 to 195psi, with alloy heads; but that's a stretch for a typical street cam with an Ica of say 61 to 66 degrees.

The thing is, with the wrong street gears/stall, there's no percentage in that either. Low-compression 318s on a budget are just hard.

Here's an example; say the cam you pick will have an Ica around 63 degrees. and say you are at 500ft elevation. To get to 160psi, the compression ratio wants to be, about 9.8 .
But to get to 185psi will need 11.1Scr. But to run that pressure, on the street with pump gas and full timing without some type of anti-knock, you would need alloy heads, and probably a tight quench.
However with a smaller cam even just one size say an Ica of 59*, Your pressures will jump to 164 and 193..
164 will require best octane gas. 193 may not run WOT on 87 gas.

So, in this case if 160psi was not enough for you at 2200 stall, perhaps 2800 would be a better solution, and/or, more rear gear, and/or less weight.

Sooner or later, you might conclude that you need 4.30gears, which then leads to an overdrive, which then runs well at 155 psi, and maybe she'll be able to run 87 gas.

It's all in the combo....... IMHO

my main question though doesn’t matter with cam profile. At TDC, will the domed 399’s physically interfere with the casting of the head? All the other stuff I’m super grateful for your input but that’s my main question. The other was WHERE DO I FIND HEAD GASKETS WITH A 318 bore combustion ring?! Everything is for “318/360” applications and that’ll kill all the math and work I do with compression. I’m an engine builder by trade however doing things on my own with my own hands is what makes me happy, like I was going to make my own pistons for this which I’ve done for other cars. What you’re mentioning beyond this isn’t stuff im really worried about I am 100% using closed chamber heads I want 920’s but they’re so darn rare 302’s are my best bet even though I want the smaller valves.

 

[waldune]

The 399 have a compression height of 1.81" and a dome height of 0.140"
The 167 have a compression height of 1.81"

9.60" - 6.123 - (3.31/2) = 1.821" - 1.81" = 0.012"

So if the deck height is 9.60" the 167 be 0.012" below and the 399 pad will be 0.128" above without any milling.

This isn’t my question, I’m not worried about compression ratios this is all stuff I understand, I’m asking if the closed chamber 302 castings will hit the dome on the piston (or 920 casting like I want but cannot find.

Second question is where to get a proper 318 head gasket as most available are cut to be used on a 360 as well so with this massive combustion ring I’ll lose the compression gains icakeewehxjabezsbrhjsbhd

 

[273]

This isn’t my question, I’m not worried about compression ratios this is all stuff I understand, I’m asking if the closed chamber 302 castings will hit the dome on the piston (or 920 casting like I want but cannot find.

Edit, my bad

Second question is where to get a proper 318 head gasket as most available are cut to be used on a 360 as well so with this massive combustion ring I’ll lose the compression gains icakeewehxjabezsbrhjsbhd

There's not as much loss as you think especially with a thin gasket.

 

[RustyRatRod]

This isn’t my question, I’m not worried about compression ratios this is all stuff I understand, I’m asking if the closed chamber 302 castings will hit the dome on the piston (or 920 casting like I want but cannot find.

Second question is where to get a proper 318 head gasket as most available are cut to be used on a 360 as well so with this massive combustion ring I’ll lose the compression gains icakeewehxjabezsbrhjsbhd

I gave you the answer. Unless there's someone on here with it mocked up, no one here knows for sure, which is why I recommended you call United Engine and Machine. They MAKE the KB pistons. Call them and they can tell you for sure. I am almost 100% positive the answer is no, you cannot use the 399 as is with 302 heads. But they can answer for sure.

 

[waldune]

What the farkin FARK did that response have to do with KB399 pistons? Just incredible.

Right??? All I wanna know is if they physically interfere with one another. I’m an engine builder by trade for stuff at home I like using a small budget and squeezing orgasm Dr

I gave you the answer. Unless there's someone on here with it mocked up, no one here knows for sure, which is why I recommended you call United Engine and Machine. They MAKE the KB pistons. Call them and they can tell you for sure. I am almost 100% positive the answer is no, you cannot use the 399 as is with 302 heads. But they can answer for sure.

okay, and anyone who has tried running them or does run them could tell me it’s why I asked here, I’ll call them and ask. The shape of everything mocked up in cad says it should fit and the closest spot is the center of the quench pad on the head which I could grind away. I’d love to get 10+ to 1 dynamic compression out of the motor with cheap mopar heads, I have a good time trying to get 1hp per cube on stock parts only but this is for something specific so can’t go nuts with custom work or forcing the BBD to flow over 300cfm and all that fun stuff haha.

I think they’ll work because the oem high comp 273 pistons don’t contact the 920 heads which are the other set that have a quench pad and smaller calves which is what I want here but they’re just too tough to find with the later intake bolt patterns, 2 years only 66-7. So 302s it is. I don’t think they will contact I was just inquiring if anyone was or had tried, like tbh you hadn’t answered my question in that reply you had a lot of good info but it wasn’t stuff I was looking for I apologize. I work as an engine builder and know mopars very well, however idk all the clearances of every aftermarket part. I may go ask on a 340 forum or 360 forum as the answer should be the same regardless of which one.

 

[waldune]

None of that was telling you the cr it was telling that the 399 piston will stick out the the bore about 0.128" which is a fair amount, (which should of been enough info answer your question) for it not to hit the head you would need a gasket with a crush measurement at least 0.168" which would be about 0.040" quench. (depending on exact measurements of everything).

There's not as much loss as you think especially with a thin gasket.

I have all that information though, that doesn’t tell me if someone has run them together before and if they had contact issues

 

[RustyRatRod]

Right??? All I wanna know is if they physically interfere with one another. I’m an engine builder by trade for stuff at home I like using a small budget and squeezing orgasm Dr

okay, and anyone who has tried running them or does run them could tell me it’s why I asked here, I’ll call them and ask. The shape of everything mocked up in cad says it should fit and the closest spot is the center of the quench pad on the head which I could grind away. I’d love to get 10+ to 1 dynamic compression out of the motor with cheap mopar heads, I have a good time trying to get 1hp per cube on stock parts only but this is for something specific so can’t go nuts with custom work or forcing the BBD to flow over 300cfm and all that fun stuff haha.

I think they’ll work because the oem high comp 273 pistons don’t contact the 920 heads which are the other set that have a quench pad and smaller calves which is what I want here but they’re just too tough to find with the later intake bolt patterns, 2 years only 66-7. So 302s it is. I don’t think they will contact I was just inquiring if anyone was or had tried, like tbh you hadn’t answered my question in that reply you had a lot of good info but it wasn’t stuff I was looking for I apologize. I work as an engine builder and know mopars very well, however idk all the clearances of every aftermarket part. I may go ask on a 340 forum or 360 forum as the answer should be the same regardless of which one.

I don't believe you'll fine anyone who's run them. Why is a phone call so damned difficult? Help me understand.

 

[waldune]

399’s with 360 heads would be my suggestion if you have those heads available. More flow, compression could be in the mid 9’s depending on chamber volume.

Yea, I’m not using bigger valve heads for a 360 because in the 318 the valves end up so shrouded that in practice on the 318 block they flow less air than the smaller valve heads. The best heads for a 318 from Chrysler are 920 castings from 66-67, they used them on the 273 as well and are closed chamber with small valves, for a street motor like I’m building for 450hp at the crank maybe 500 you don’t need more air flow than the 318 or 273 heads give you because of shrouding, a ported set of 920’s or 302’s on the dyno at work and flow volume through the engine itself as it rotates, the close chamber small valve heads are best. This ONLY goes for the 318 because of its tiny bore, a 340 has enough of a bore where larger valves don’t get shrouded enough to impede flow. And after basic porting I get more port velocity from small valve 920’s than even the 302’s. Now flat top pistons would get me good compression on this build but the small domes on the 399’s share very closely their design for the domed high comp 263 pistons which used the 920 heads, essentially the same as the 302’s with bigger valves and minor minor differences so I think they should fit, and with the quench pad and finding the right head gasket I should have good control over detonation as well. I’ve built a bunch of 400+ crank hp 318’s, used KYB 167’s that are flat tops that actually reach 0 deck inline oem clevite flat tops. Being one goal of this is to hopefully not machine it at all if I have to I will at work. Strongly considering making my own pistons because I don’t need them to be forged, I’ve made plenty of pistons before for pre war rebuilds when things just are not available anywhere

 

[waldune]

I don't believe you'll fine anyone who's run them. Why is a phone call so damned difficult? Help me understand.

Well a phone call vs asking the largest repository of people who may have tried this before, this makes sense for real world application experience. People run high comp pistons in 273’s with the same heads and they have the same basic design but they are made by a different company so I am wondering if anyone has run them or tried to run them, if there a slight point of contact I’ll grind the head a bit but these appear to basically be a 318 version of a 273 high comp piston so in theory it should work, the dimensions look like it should work, the issue is idk if the casting shape is a problem. Figured I’d ask in the one place I’d be able to find others who have done higher compression small blocks. Ive used these pistoms on very custom stuff just never chrysler heads. im juet doing another budgey build, i usually use kyb 167's for these at 0 deck and were able to use factory heads and my porting has gotten mosy all of them to 450 crank minimum, the idea of maybe getting 500 crank out of a 318 that has only pistons, cam, intake carb and headers is enticing. i love getting a lot out of mostly factory stuff. had a 500cfm 2 barrel on my 61 lancer turbo slant build years ago

 

[waldune]

None of that was telling you the cr it was telling that the 399 piston will stick out the the bore about 0.128" which is a fair amount, (which should of been enough info answer your question) for it not to hit the head you would need a gasket with a crush measurement at least 0.168" which would be about 0.040" quench. (depending on exact measurements of everything).

There's not as much loss as you think especially with a thin gasket.

Again i don’t have the measurement of the deck to lowest point in the combustion chamber to the highest point on the piston and even if I did idk if that’s where there would be interference. Those measurements don’t help it’s the shape of each that I need to know if lines up the or not

 

[AJ/FormS]

I’d love to get 10+ to 1 dynamic compression out of the motor with cheap mopar heads,

Shooting for a DYNAMIC of 10:1 will get you into race-gas territory.
Again, depending on your Ica, say with a modest 62*, that will require about a 12.5 Scr, to net around 220 psi.
To get that pressure down to say 165psi, for best street gas, the Ica would need to be ...... are you ready .... 84 degrees. and your bottom end, by V/P comparisons would be about as strong as a factory 8/1, 273 2bbl.
Do you know how big a cam it takes to get an Ica of 84 degrees?
That could easily be around 308 degrees advertised at .008 tappet rise.

Working the math backwards, for a 318, your TOTAL chamber volume would need to be about 56 to 57cc. That's TOTAL.
Since you're an engine builder,
maybe you know how to make that run on the street,
with pop-up pistons, factory iron heads, and the monster cam which is NOT gonna run in those chambers until you make room for the Lift that would be associated with such a cam. and then the eyebrows are gonna cost you compression, if indeed you don't mill right thru the crowns.

IMHO, you are not thinking straight. If you made a bet with a buddy that you could do it, just pay the man.

But even if you could,
the question is why?

I'm not following yur thinking at all. That's gonna be a top-end racer, requiring a lotta stall, and race-gears in the back. and you'll have to stock race gas at how much a gallon?

This is would never be a street engine. and it would likely be well beyond rowdy, if you could even get it started for the cam-break-in.
But hey, I'm not a builder. They call me a Keyboard Kommando. But, if you want a fantastic recipe for a 360, I could be yur man. Mine is a real brawler.

 

[273]

I have all that information though, that doesn’t tell me if someone has run them together before and if they had contact issues

Edit, I'm sorry I mixed the kb 399 pistons with ones that had a quench pad.

 

[273]

Yea, I’m not using bigger valve heads for a 360 because in the 318 the valves end up so shrouded that in practice on the 318 block they flow less air than the smaller valve heads. The best heads for a 318 from Chrysler are 920 castings from 66-67, they used them on the 273 as well and are closed chamber with small valves, for a street motor like I’m building for 450hp at the crank maybe 500 you don’t need more air flow than the 318 or 273 heads give you because of shrouding, a ported set of 920’s or 302’s on the dyno at work and flow volume through the engine itself as it rotates, the close chamber small valve heads are best.

Says who ? The problem when you look at only one or two factors and ignore the rest.

Could a 273/318 be ported out to make 450-500 hp possibly but very very unlikely especially if not done by a great head porter.

This ONLY goes for the 318 because of its tiny bore, a 340 has enough of a bore where larger valves don’t get shrouded enough to impede flow.

340 bore definitely better but 318 bore is still a fairly large bore especially with an overbore.

1.78 valves and heads were designed with 273 bore and displacement in mind, not a 318. A 318 bore is .285" bigger than a 273 bore basically a similar difference between a 318 and a 413 bore, a 318 is a lot closer to a 360/340 bore size then either a 273/413 especially after a 0.030-0.060" bore job. 4.8/5.3l LS only haves a 3.78" which would make 318 be bigger by a 0.130" which is same difference between 318 and 340.

 

[273]

Here's a pic of a kb 399 in the block, if the spark plug side ain't to different from the open chambers could fit but probably be very high cr.

Headgasket for Kb399 and 302 Heads

 

[RustyRatRod]

Here's a pic of a kb 399 in the block, if the spark plug side ain't to different from the open chambers could fit but probably be very high cr.

View attachment 1716401698
Headgasket for Kb399 and 302 Heads

I don't think there's a ghost of a chance in hades that that dome will clear the head, even on the spark plug side. That's what they're made for. To mill for quench. A 2 minute phone call will solve the question.

 

[273]

I don't think there's a ghost of a chance in hades that that dome will clear the head, even on the spark plug side. That's what they're made for. To mill for quench. A 2 minute phone call will solve the question.

I agree the wises move is to call.

From what I got from the thread I got the pic from 72DMag says he measure and found clearance but like you said I'd still call to make sure.

Sorry for late response!! Life has been little crazy.

@rumblefish360 the flat part of the piston is basically zero deck at .005 in the hole. When I did the putty on the 302 heads with the dome of piston. There was plenty of room. closes thing was the spark plug. With the head bolted on and NO headgasket I got .188 clearance measuring the puddy from tip of spark plug to the dome.

I dont see a reason why that wont work. My concern at this point is valve lift. On intake with piston at TDC I got .353 when the valve hits piston. On exhaust I got about the same. Fyi these are stock valves in the 302 heads.

The cam I wanted to run is a hydraulic roller and I was going to use solid roller lifters. The cam has 468 lift on intake and 475 lift on exhaust with 1.5 ratio rockers. Duration at .050 is 230 on intake and 234 on exhaust. Valve timing events are as follows. Intake opens 7 btdc and closes 43 abdc. Exhaust open 45 bbdc and closes 9 atdc.

I'm far from a cam expert but I'm afraid there might be no room for that lift with these heads and the kb399 pistons. Sigh can someone more knowledgeable confirm that?

I know you guys like pics so I attached a bunch. Yes the bench in background is a mess

View attachment 1716012596



View attachment 1716012598

View attachment 1716012599

 

[RustyRatRod]

I agree the wises move is to call.

From what I got from the thread I got the pic from 72DMag says he measure and found clearance but like you said I'd still call to make sure.

It's one of those instances where you want to be 100% SURE. Even if UEM says it will clear, that's not enough for me. I have to measure. It's not worth the consequences if somehow someone is incorrect, OR if your combination is somehow "off the map".