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Hi everyone.
I am starting a new build thread for my new engine.
Before I continue I was contacted by a moderator who is going to monitor this new thread and keep a close eye to see if any garbage gets posted or name calling occurs because of all the other previous disruptions.
Everyone is welcome to give their opinions and suggestions. I don't expect everyone to agree with everything written here either.
No need to name call, or slander someone's build. So keep it respectful.
Now that this is out of the way let the build begin!
As many of you have been following, my last engine is not going to be completed due to the various issues.
I'm starting on a clean slate and going to build something that I have been wanting for a long time.
"A relentless torque monster". That is also fun to drive.
Here are the specs:
Dart LS block Pro Iron 434 CID 4.155 bore -3.68CC dish pistons.
Mamo 245cc heads with all options plus 10mm threads 65CC chambers (Of course assembled and ready to go and with hollow stem valves) 12:5.1 compression
Mamo Ported FAST 102mm
Mamo Yella Terra rockers
Manley NEXTTEK spring kit
Nick Williams 102mm DBW throttle body
TCE 3500RPM stall converter
Mezeire Electric Water pump 55GPM
Morel 5452 solid lifters
Comp cams solid roller (specs are not confirmed yet but am open to suggestions)
I know some of you have been saying why I am not using an LS7 head on this size engine and bore?
After speaking with Mamo about my goals and what I want to achieve, the LS7 is not the head of choice for this build even though it will make a higher peak power figure at a higher RPM.
The 245CC head straight from AFR flows enough for a 454 so I don't see any issue with this head cylinder not being able to flow enough for the engine.
My thoughts are if the Mamo version is about 250CC then there certainly will not be an issue.
If you check out the following link you will see a direct comparison on a 427 with the TFS LS7 and a 245CC Trickflow.
You will notice that the trickflow was far stronger down low all the way too 5800rpm before the ls7 head took over.
You will also notice that the trickflow also made more peak torque and across a far wider rpm range compared to the LS7 head.
I can imagine the gains down low off idle to 3000rpm.
There was also only a 10hp peak difference.
This is without Tony's 245CC reworked head which is a superior piece compared to this one being tested.
I'm only planning a rev limit of around 7300rpm so it should work out well.
In regards to not getting a different crank and maxing out the bore size.
It's a safer bet to use the 4 inch crank.
Less stress on parts at higher rpm's because of shorter stroke and a 434 engine size is enough.
Plus I save money by not having to purchase another crank and rods.
The crankshaft is a forged K1.
I did not max out the bore size to 4.185 because then I would leave no room for future rebuilds and this is the max bore size that the engine can go to safely.
A 4.155 bore is right in the middle and is a good compromise. (Mamo's suggestion)
It's safe for boost too but if I was to go down this route far into the future I would upgrade my crank and rods as a precaution due to the stupendous power the engine would make.
Intake choice: FAST 102mm or MSD? Driveability?
Here are the answers from Tony himself:
A ported MSD is never going to give you the low and midrange torque of the FAST....we are picking those numbers up with the additional displacement....the MSD is what is going to get you that balanced curve with a sexy top end to compliment the more than adequate torque figures this engine will produce purely based on displacement and airspeed in the head. Its what is going to get you closer to rect port HP numbers and allow the large cathedral head engine to carry further in the higher RPM range where all the big HP is always made.
The largest difference from the square port stuff to the cathedral is ALL your part throttle operation and responsiveness which is never seen or measured on a dyno. A square port head never feels razor sharp until the RPM's are up and you start getting some velocity going in the port. Based on all you have shared with me I think the cathedral version of this engine will give you exactly what your after. The square port will make a sexier peak number on the dyno but you aren't driving a dyno and your especially not driving a dyno at part throttle which is 95% of your time behind the wheel.
Couldn't say it any clearer myself.
Power is expected to be around 700hp give or take.
Ill do a video for you tomorrow to show you that a lot of what you just said here is a load of ****. I just cranked out 600kms, smooth as butter, 1400rpm top gear, oh and you worrying about torque, rained on the way home ,still top gear 1400rpm , 110kmh, oops hit a bump and tapped the throttle , sideways for the next km. oh and brand new rubber, or that i cant give 100% throttle until well into 3rd gear in the dry with super sticky sport cup rubber, damn i can nearly stall it and stab the throttle and itll light up
No-one is gunna say anything but ls7 heads, dont delude yourself into thinking the 245s are in any way better. The ls7 heads with a cam to suit your style will smash the 245s with a cam to suit your style, and thatll be from 0rpm to as high as you like. Think, Cubic Inches
I can understand your crank, mayb the bore, theory, but the heads, you just cant justify any of the dribble u said saying the 245s are better for your application .
maybe you'll wake from the sleep typing nightmare and deny you knew anything about it
Below is a dyno graph of my AHP 434 Build w/their 265 Archangel/BR7 head for a baseline. This is with a ported MSD and 4:10’s with 1 3/4 LGM headers into stock mufflers.
Before the MSD, injection and tuning it did 700 flat on the engine dyno at break in at Westech.
Boris,
My heart feels for you and the unfortunate luck u had during the last build. I personally think you will like the cathedral port motor better. Whose gonna spec the cam, Tony or CamMotion?
700 @ the crank, maybe, possible, going to take a big LLSR something like ~ 249/257 (standard ex port) .680"/.660" ~114+3 Minimum, with a ~7000 Peak.
750!!! No Way with Cathedrals & MSD.
Rich Willhoff's Katech Built 434" made 757 HP @ ~7200 check out his build.
Not saying dont build with cathedrals just be more realistic.
jmo & .02
Good Luck
Boris,
My heart feels for you and the unfortunate luck u had during the last build. I personally think you will like the cathedral port motor better. Whose gonna spec the cam, Tony or CamMotion?
Im pretty sure he specs cams, especially his own iirc. I like that its a different kind of build vs. max effort stuff. I always thought Ls7 heads were a more effecient and better performing head all around. Im no expert. Just what I interpreted before, during, and after my build. I say pick the builder you wanna use first, than you two hash out a plan, and execute. Screw every other opinion, you ll go nuts chasing your tail and 2nd guessing. Im going thru it myself. Especially everytime another build pops up,lol. Sounds like you guys have a plan. Now attack n get some pics up asap! Good luck with the project too!
Every 4.1something bore combo deserves nothing but a square port LS7 head otherwise you're just leaving power on the table. I'd have to disagree with the statement that a square head wouldn't feel razor sharp down low... it's all about building the right combo which includes the right cam, converter and gearing.
Ill do a video for you tomorrow to show you that a lot of what you just said here is a load of ****. I just cranked out 600kms, smooth as butter, 1400rpm top gear, oh and you worrying about torque, rained on the way home ,still top gear 1400rpm , 110kmh, oops hit a bump and tapped the throttle , sideways for the next km. oh and brand new rubber, or that i cant give 100% throttle until well into 3rd gear in the dry with super sticky sport cup rubber, damn i can nearly stall it and stab the throttle and itll light up
No-one is gunna say anything but ls7 heads, dont delude yourself into thinking the 245s are in any way better. The ls7 heads with a cam to suit your style will smash the 245s with a cam to suit your style, and thatll be from 0rpm to as high as you like. Think, Cubic Inches
I can understand your crank, mayb the bore, theory, but the heads, you just cant justify any of the dribble u said saying the 245s are better for your application .
maybe you'll wake from the sleep typing nightmare and deny you knew anything about it
Whoa man relax.
It certainly was not my intention to **** you off.
Let me get a few things straight here.
First of all I never said the LS7 heads don't make torque down low.
Especially on large cubed motors like yours. They do. You have a 454. 20 more cubes than me which would only help the low end further.
Also the pilot sport cup rubber tyres are terrible in the wet so I'm not surprised even at that low rpm they can spin.
They are fantastic in the dry though. I know because I had them once too.
I also never said the LS7's heads are inferior to the AFR cathedral.
I clearly stated that the LS7 heads will make more peak power at a higher RPM compared to the AFR 245CC.
It is also a fact that the cathedral 245cc will be quite a bit stronger down low off idle till about 6000rpm.
This is coming from Mamo.
Did you check out the link also??
Did you read the last paragraph what Tony wrote about the responsiveness of each head?
If so, are you saying he is full of it?
You can't really compare the two because you haven't experienced what it feels like to drive a cathedral headed large cubed engine.
Tony has and he is a professional and knows what the peak hp losses are and it's not as much as you probably are assuming either especially up around the 7000rpm range.
I doubt very much Tony would recommend me a head that would not suit or perform and make himself and me look stupid.
Don't forget this AFR head supports up to 454 engines so I doubt AFR are lying here by listing it on their website.
But you are right, a cam to suit my style with both heads, the LS7 will in most cases make more PEAK power, BUT it will be down in tq and HP from around 6000rpm and below.
This is why I am using the Fast 102 for the cathedral setup.
To use more cam timing and sacrifice some low and midrange power to make some more top end as the low end will be plentiful and it will pull higher to about 7000rpm to make peak numbers closer to the LS7.
The 245 head also allows us to run more cam too.
Also, the bore size theories are not opinions. They are facts.
I want to leave room for a possible rebuild.
This nightmare is killing me. lol
It's pretty easy for me to change my mind and secure that other top end for sale.
And yes post a video.
I don't doubt what you said about the engine pulling but I would like to see.
If Tony is reading this it would be nice of him to chime in and clear a few things up.
Below is a dyno graph of my AHP 434 Build w/their 265 Archangel/BR7 head for a baseline. This is with a ported MSD and 4:10’s with 1 3/4 LGM headers into stock mufflers.
Before the MSD, injection and tuning it did 700 flat on the engine dyno at break in at Westech.
That's a strange looking dyno curve.
Why is it all jagged?
Was the MSD from Mamo?
Boris,
My heart feels for you and the unfortunate luck u had during the last build. I personally think you will like the cathedral port motor better. Whose gonna spec the cam, Tony or CamMotion?
Last build was unfortunate but it turned out good in a way. I had been wanting to for a long time build something really good.
A lot of the parts are being sold soon so I will be able to recoup some $ back.
The cathedral headed motor will be a blast to drive. It will pull very hard at all RPM's which is what I want.
Most likely Tony or Pat G will spec the camshaft.
They are both good.
I like them both.
700 @ the crank, maybe, possible, going to take a big LLSR something like ~ 249/257 (standard ex port) .680"/.660" ~114+3 Minimum, with a ~7000 Peak.
750!!! No Way with Cathedrals & MSD.
Rich Willhoff's Katech Built 434" made 757 HP @ ~7200 check out his build.
Not saying dont build with cathedrals just be more realistic.
jmo & .02
Good Luck
Navy....for the record, that's what I told him we could make....about 700 at the crank
To help us achieve that this engine will have about 12 to 1 compression and a fairly stout solid roller I will likely spec....the MSD will also help us achieve that number helping to carry torque past 6000 RPM.
I had never mentioned higher than that figure just so everyone is clear....could it make a little more.....sure in a perfect world it actually might but 750 is most assuredly out of the question
I have exchanged over 75 emails with Peter (the OP) over the last couple of years.....30 alone in the last couple of weeks and I have a pretty good idea of what he is looking for and peak power is not as important to him as area under the curve and part throttle fun and response is.
Anyone that truly knows me knows that I have focused alot of Mamo Motorsports R&D time in the last few years dedicated to my LS7 products....Im a huge fan of the platform and I have been killing it with big power combo's that I design the complete top ends for (heads, cams, induction, and valvetrain). Most of these guys are more aggressive in nature and are installing them in very light Corvettes.
This build has very different requirements and the owner's focus is a build looking for alot of area under the curve and he is very focused on light to light street driving and wants it really responsive and values that part throttle low RPM grunt.
A larger cube motor with good flowing cathedrals (and the help of my MSD to extend the RPM up top) should give him just that.
Did I offer to help him with my LS7 gear....of course.....did I feel that was the right choice for what he was looking for....not really.
This engine is still going to produce respectable peak numbers but have a really wide usable power curve and it will feel awesome down low as only a big inch engine with a modest sized set of high flow heads can.
My opinion is this combo covered the bulk of this particular customers needs....it checked most if not all the boxes. That doesnt mean it would do the same for others reading this so don't be quick to judge and throw out an opinion without knowing the key facts
What the OP was looking for was/is unique.....as most builds are in some form or fashion. Designing it properly is always going to be different based on who's *** is sitting in the drivers seat, what they are exactly focusing on and looking for from the build and naturally evaluating the vehicle itself which might shift some components choices around based on weight, transmission style, gear ratio and other factors including the target application itself which is very important (it it mainly a street car....street strip.....a race car we are driving on the street....etc., etc.)
I hope some of you find what I just posted helpful even as it relates to your own build. Design the build to focus on what your wanting for the end results....not what others less informed on your goals think it should be.
Then consider enlisting the help of a professional with a proven track record to help you get there if you don't personally have the knowledge and years of experience and understanding of all the components involved and how they all effect one another.
When I tell you that this combo we settled on was well thought out over a long period of time that would be a huge understatement.
Its still not too late for the OP to switch gears and go square port, but knowing what I know in the detail that I know it, I still feel its the wrong play for him and doesn't check off as many boxes. Yes it would make more peak power but it compromises some of the other goals that are clearly important to him compromising what he is looking to experience in 98% of his driving for the slightly stronger surge he would feel in 2% of his driving at WOT (but hey.....his dyno sheet in the glove box would look a touch more impressive).
Anyway.....that's it for now....I will revisit this thread again Im sure.
Sounds like Mamo is telling you what you want to hear.
If you’re going to lay out the cash for a new top end why would you not buy the discounted Mamo ls7 setup from the classifieds?
If Mamo is telling me what I want to hear, shame on him.
He doesn't strike me as someone who would do something like this.
But you have a good point about that ls7 top end.
I was seriously considering it at one stage.
I was going to make a deposit.
It's all packed and ready to go.
But as stated, the cathedral setup is what will give me what I am after and at a lower rpm too.
I also need to consider my 4L65E transmission.
These units do not like to be revved out too far which was another reason I went with this setup.
Car is also heavy 1800KG with me in it.
Navy....for the record, that's what I told him we could make....about 700 at the crank
To help us achieve that this engine will have about 12 to 1 compression and a fairly stout solid roller I will likely spec....the MSD will also help us achieve that number helping to carry torque past 6000 RPM.
I had never mentioned higher than that figure just so everyone is clear....could it make a little more.....sure in a perfect world it actually might but 750 is most assuredly out of the question
I have exchanged over 75 emails with Peter (the OP) over the last couple of years.....30 alone in the last couple of weeks and I have a pretty good idea of what he is looking for and peak power is not as important to him as area under the curve and part throttle fun and response is.
Anyone that truly knows me knows that I have focused alot of Mamo Motorsports R&D time in the last few years dedicated to my LS7 products....Im a huge fan of the platform and I have been killing it with big power combo's that I design the complete top ends for (heads, cams, induction, and valvetrain). Most of these guys are more aggressive in nature and are installing them in very light Corvettes.
This build has very different requirements and the owner's focus is a build looking for alot of area under the curve and he is very focused on light to light street driving and wants it really responsive and values that part throttle low RPM grunt.
A larger cube motor with good flowing cathedrals (and the help of my MSD to extend the RPM up top) should give him just that.
Did I offer to help him with my LS7 gear....of course.....did I feel that was the right choice for what he was looking for....not really.
This engine is still going to produce respectable peak numbers but have a really wide usable power curve and it will feel awesome down low as only a big inch engine with a modest sized set of high flow heads can.
My opinion is this combo covered the bulk of this particular customers needs....it checked most if not all the boxes. That doesnt mean it would do the same for others reading this so don't be quick to judge and throw out an opinion without knowing the key facts
What the OP was looking for was/is unique.....as most builds are in some form or fashion. Designing it properly is always going to be different based on who's *** is sitting in the drivers seat, what they are exactly focusing on and looking for from the build and naturally evaluating the vehicle itself which might shift some components choices around based on weight, transmission style, gear ratio and other factors including the target application itself which is very important (it it mainly a street car....street strip.....a race car we are driving on the street....etc., etc.)
I hope some of you find what I just posted helpful even as it relates to your own build. Design the build to focus on what your wanting for the end results....not what others less informed on your goals think it should be.
Then consider enlisting the help of a professional with a proven track record to help you get there if you don't personally have the knowledge and years of experience and understanding of all the components involved and how they all effect one another.
When I tell you that this combo we settled on was well thought out over a long period of time that would be a huge understatement.
Its still not too late for the OP to switch gears and go square port, but knowing what I know in the detail that I know it, I still feel its the wrong play for him and doesn't check off as many boxes. Yes it would make more peak power but it compromises some of the other goals that are clearly important to him compromising what he is looking to experience in 98% of his driving for the slightly stronger surge he would feel in 2% of his driving at WOT (but hey.....his dyno sheet in the glove box would look a touch more impressive).
Anyway.....that's it for now....I will revisit this thread again Im sure.
Regards,
Tony
Thanks for chiming in.
Tony is right but I did over estimate the hp figure.
It should reach 700hp maybe a little more but not 750hp.
I knew this but it may have not come across that way with the way I typed it.
Tony and I did exchange so many emails to come up with the final plan.
I'm happy with what I am doing and so is Tony.
The only thing I am sacrificing by not going with the LS7 head is peak power and higher rpm capability which are not of primary importance.
Everything else is in favour to the cathedrals for my application and this is what we went over countless times.
I know some of you might not agree or think it's the wrong move.
But it's ok.
Everyone is entitled to their opinion.
02-15-2020, 06:24 AM
Dart SHP Pro Iron 434 
