High RPM recipe
02-24-2008, 07:22 PM
#12
4th Gear Member
Join Date: Mar 2005
Location: California
Posts: 1,471
RE: High RPM recipe
ORIGINAL: baha
In need of 7000-7500rpm capability? here is the recipe:
1) Full exhaust (LTs, o/r X or H pipe)
2) C&L 95mm racer intake
3) GT500 Throttle body
4) Stage 3 Heads
5) Upgraded valvetrain
6) Forged Internals + bumping compression to 10.5:1-11:1
7) Higher capacity oil pan
8) Bigger Injectors maybe needed?
9) Delete plates
Did I miss something? I didn't list any cams 'cause lots of guys say the stock ones are good for 7000+rpms
Those mods of course need serious gears 4.10-4.56
In need of 7000-7500rpm capability? here is the recipe:
1) Full exhaust (LTs, o/r X or H pipe)
2) C&L 95mm racer intake
3) GT500 Throttle body
4) Stage 3 Heads
5) Upgraded valvetrain
6) Forged Internals + bumping compression to 10.5:1-11:1
7) Higher capacity oil pan
8) Bigger Injectors maybe needed?
9) Delete plates
Did I miss something? I didn't list any cams 'cause lots of guys say the stock ones are good for 7000+rpms
Those mods of course need serious gears 4.10-4.56
To build a high powered N/A motor that will pull hard in the upper RPM range you will need some HOT cams with plenty of overlap, the Comp Stage 3 cams are not hot enough. At this point you realize this is no longer going to be a nice street engine that will pass smog testingever again.You will also likely have to lock out the VVT to get stable cam timming at that RPM. Call and ask Comp about their lightweight Ti retainers, locksand stiffer springs, not thecatalog beehives, they makea stiffer spring and you will need it per Comp tech repsI've spoken to atNHRA national events. There are alsoworries with the followers and hydralic lifter weight, you need to consider dumping the hydralicsand replacing them with mechanical lash adjusters to avoid pump up and gain better valvetrain control.I would also suggest the larger BBK twin 62mmthrottle body because the port shape is designed to match theS197GT's plastic intake manifold unlike the GT500 T/Bwhich requires the use of a spacer to reduce the T/B openingdue to the widerbore spacing of theGT500 T/B.You don't need monster head porting at all but youmaywant todo a simple port match of your completeintake tract fromthe intake to your CMCV deletes and to the head's ports. The layback of the ridges covering the valves in the chambers is important toimprove airflow into the cyclinder as is increased compressionwhich you will need formost high RPM cams to work effectively. Hotter COP's and larger injectors are going to be needed too.
HTH!
02-24-2008, 08:23 PM
#13
3rd Gear Member
Join Date: Apr 2007
Location: Pa
Posts: 763
RE: High RPM recipe
Hmmm... I understand your goals of wanting big power NA... but I really think your kinda going at it from the wrong angle, especially if your looking to keep it street legal. To keep making power up that high, your going to be making Big sacrifices down low to get the ability to spin up... which will amount to your car coming out of the hole like a slug unless you go with some pretty steep gears...
But never the less, I think it sounds like an interesting idea and a project that will be a learning experience for the mustang community as a whole. If you decide to go this route, please keep us up to date.
But never the less, I think it sounds like an interesting idea and a project that will be a learning experience for the mustang community as a whole. If you decide to go this route, please keep us up to date.
02-25-2008, 05:04 AM
#14
3rd Gear Member
Thread Starter
Join Date: Nov 2003
Location:
Posts: 585
RE: High RPM recipe
My reason is to stay NA and run mid to low 11s (10s are a dream) and stay streetable. 2 ways to do that: Big displacement or squeeze the life out of the enigne with very high rpms, I thought of all the possibilities and came up with the following:
1) The biggest modular ever produced (5.8L): a big bore iron 5.4L block= too expensive
2) A normal 5.4L iron block with full bolt-ons, heads, camsand 10.5:1 compression = still expensive
3) Spin the 4.6L to very high rpms = Complicated!!!
4) I even considered putting a 408W or a big block under the hood = Complicated
Boost is my choice now..
Thanks to Spyder, F1Fan, GT Bob and everyone else for your input.
1) The biggest modular ever produced (5.8L): a big bore iron 5.4L block= too expensive
2) A normal 5.4L iron block with full bolt-ons, heads, camsand 10.5:1 compression = still expensive
3) Spin the 4.6L to very high rpms = Complicated!!!
4) I even considered putting a 408W or a big block under the hood = Complicated
Boost is my choice now..
Thanks to Spyder, F1Fan, GT Bob and everyone else for your input.
02-25-2008, 06:23 AM
#15
4th Gear Member
Join Date: Apr 2006
Location:
Posts: 1,541
RE: High RPM recipe
High RPMs and propergearing do seem to be the keys to winning races. Shifting gears will lose time making power and the longer you can make power the less time you'll have to shift. That IMO is why so many supras beat so many cobras.So your not wrong in seeking high rpm power. Just take into consideration what it may cost you streetability, emissions, etc.
02-25-2008, 03:05 PM
#16
4th Gear Member
Join Date: Nov 2007
Location:
Posts: 1,699
RE: High RPM recipe
ORIGINAL: spyder7724
I think you are on the right track with everything but you really want to consider locking out the VCT if you plan on running above 7000rpms. The problem is that you will need a valve spring much stronger than what the phasers can deal with. This will lead to erratic camshaft timing which loses power and can destroy an engine very quickly.
My new engine is going to be a high rpm N/A engine. I have my reasons for building this type combination even though it would be easy to slap a s/c on have 400rwhp tomorrow.
here's what we are building to hopefully have a 10second N/A S197 GT:
5.4 iron block (3.625 bore with stock 4.165 stroke)=344cid
12:1 compression custom pistons gas ported & fly cut
lightweight I-beam rods
steel crank (knife edged and lightened)
thin low drag ring set
CNC ported heads 300cfm intake/200cfm exhaust
custom crane solid roller camshafts 550/600 lift 245/260 duration 114 centerline
Crane valve springs with titanium retainers
solid lash adjusters
modified sullivan single plane intake manifold or sheetmetal intake
twin 60mm t/b maybe twin 70mm
I'm hoping on a minimum of 425+rwhp n/a and shooting for 500+rwhp.
expected rpm of may power=7500-7800rpms
the intake manifold is going to be a huge part of the high rpm equation. the stock intake works great for most of us but it signs off at about 5600rpms. you can still rev the engine past this but the intake is no longer efficient and is costing power. there's a couple companies making intakes but only one that I've seen in person and see the dyno #'s on which actually makes more power than stock above 5000rpms. It's not available yet but will be soon. You may want to look at some options for this also.
good luck and glad to see someone else doing it all natural
I think you are on the right track with everything but you really want to consider locking out the VCT if you plan on running above 7000rpms. The problem is that you will need a valve spring much stronger than what the phasers can deal with. This will lead to erratic camshaft timing which loses power and can destroy an engine very quickly.
My new engine is going to be a high rpm N/A engine. I have my reasons for building this type combination even though it would be easy to slap a s/c on have 400rwhp tomorrow.
here's what we are building to hopefully have a 10second N/A S197 GT:
5.4 iron block (3.625 bore with stock 4.165 stroke)=344cid
12:1 compression custom pistons gas ported & fly cut
lightweight I-beam rods
steel crank (knife edged and lightened)
thin low drag ring set
CNC ported heads 300cfm intake/200cfm exhaust
custom crane solid roller camshafts 550/600 lift 245/260 duration 114 centerline
Crane valve springs with titanium retainers
solid lash adjusters
modified sullivan single plane intake manifold or sheetmetal intake
twin 60mm t/b maybe twin 70mm
I'm hoping on a minimum of 425+rwhp n/a and shooting for 500+rwhp.
expected rpm of may power=7500-7800rpms
the intake manifold is going to be a huge part of the high rpm equation. the stock intake works great for most of us but it signs off at about 5600rpms. you can still rev the engine past this but the intake is no longer efficient and is costing power. there's a couple companies making intakes but only one that I've seen in person and see the dyno #'s on which actually makes more power than stock above 5000rpms. It's not available yet but will be soon. You may want to look at some options for this also.
good luck and glad to see someone else doing it all natural
Remember guys, yes, you 'can' spin the stock cams up there but with greater rpm cause greater risk and I wouldn't attempt to spin the car that high on ANY set-up on the stock bottom end. A stout motor should be first on the list before deciding how high to spin it IMO...
02-26-2008, 03:32 AM
#17
3rd Gear Member
Thread Starter
Join Date: Nov 2003
Location:
Posts: 585
RE: High RPM recipe
ORIGINAL: modaddict
^^^ now that's a list. Locking out the VCT is mandatory IMO too but few around this site rarely talk about it. I'm excited to see this thing come around, Ron - it's going to be awesome!
Remember guys, yes, you 'can' spin the stock cams up there but with greater rpm cause greater risk and I wouldn't attempt to spin the car that high on ANY set-up on the stock bottom end. A stout motor should be first on the list before deciding how high to spin it IMO...
^^^ now that's a list. Locking out the VCT is mandatory IMO too but few around this site rarely talk about it. I'm excited to see this thing come around, Ron - it's going to be awesome!
Remember guys, yes, you 'can' spin the stock cams up there but with greater rpm cause greater risk and I wouldn't attempt to spin the car that high on ANY set-up on the stock bottom end. A stout motor should be first on the list before deciding how high to spin it IMO...
So with my original list, is it enough to move the power band to 7000rpms? what I want exactly is an engine that shifts at 7K rpms with a 4.56 gears intead of the 4.10s I have now.
My car now shifts at about 6300rpms with Brenspeeds tune, I've wanted the 4.56 gears, but those gears need higher shift points IMO.
Your advice?
02-26-2008, 01:22 PM
#18
4th Gear Member
Join Date: Nov 2007
Location:
Posts: 1,699
RE: High RPM recipe
I shifted my car on the stock motor at 7000 rpms with the vortech and 4.10 gears for a year with no issues but I always knew it could go at anytime. I really don't think there is a 'safe' way to spin that high on the stock motor. Upgrading your valve train will definitely help and reduce the risk though.
Thread
Thread Starter
Forum
Replies
Last Post
mungodrums
Suspension
0
09-24-2015 10:12 PM
