engine build options for FI

[Forge]

I currently have a Hellion mustang GT with 480 rwhp at 9 psi. I want more.

Im mostly a old windsor guy (stroked 351's in fox bodies) so im relatively new to the modular engines. few questions to start

1. Ive heard with FI, the 3v heads should be good to 800ish wrhp? true or false?
2. Ive heard the blocks are as strong, if not stronger then tesklid (sp) blocks and should hold 800 rwhp all day. True or false?
3. Ive also heard the cobra cranks shoudl also hold 800 rwhp. True or false?

Here is my thing, i would like a 650-700 rwhp daily driven car (not in the winter). I would like to get 50k miles out of the engine. I want to use my current block to keep weight down in the front, as its not a drag car, it will also see alot of streets, road course, and autox (mostly spirited highway driving). Im looking for advice on parts and good places to buy them. I sent Larry_H a PM on another board, but he hasnt got back with me in a while, so i figured i would ask here. Is there any extra parts i might need other than a flywheel and clutch? I using the Twin Ford GT Super car pumps that should be good to 800ish rwhp with some wiring, fuee lines, rails and injectors.

 

[cekim]

I currently have a Hellion mustang GT with 480 rwhp at 9 psi. I want more.

Im mostly a old windsor guy (stroked 351's in fox bodies) so im relatively new to the modular engines. few questions to start

1. Ive heard with FI, the 3v heads should be good to 800ish wrhp? true or false?
2. Ive heard the blocks are as strong, if not stronger then tesklid (sp) blocks and should hold 800 rwhp all day. True or false?
3. Ive also heard the cobra cranks shoudl also hold 800 rwhp. True or false?

Here is my thing, i would like a 650-700 rwhp daily driven car (not in the winter). I would like to get 50k miles out of the engine. I want to use my current block to keep weight down in the front, as its not a drag car, it will also see alot of streets, road course, and autox (mostly spirited highway driving). Im looking for advice on parts and good places to buy them. I sent Larry_H a PM on another board, but he hasnt got back with me in a while, so i figured i would ask here. Is there any extra parts i might need other than a flywheel and clutch? I using the Twin Ford GT Super car pumps that should be good to 800ish rwhp with some wiring, fuee lines, rails and injectors.

All 3 above are true. 3V heads and block (at least in terms of strength) have gone to 800 and beyond (with a cobra crank and forged rods of course).

With regard to the teksid - the 05+ block is reported to be stronger than the teksid, but:
a. more expensive - 2x or more
b. teksid is plenty strong and will more than meet your needs.

For your power range you will need rods, pistons and crank of course. Stock fuel rails should be fine with 60lb injectors. GT500 dual pump should be fine at that level, though depending on where you live, you might be on the edge - think about dual BAP if you find you are running out of fuel at the top.

You are pushing the driveline very hard at this power level - it will break.

Upgraded trans (26 spline input shaft for a manual, built 5R55x or similar for the auto).

For the street that power shouldn't be too much of a problem, but without taking 500lbs out of the car - that sort of power will tear up the rear with a manual at least. You will get further with an auto, but eventually kill it. Axle housing brace, differential and axles are in order there...

 

[Forge]

You are pushing the driveline very hard at this power level - it will break.

Upgraded trans (26 spline input shaft for a manual, built 5R55x or similar for the auto).

For the street that power shouldn't be too much of a problem, but without taking 500lbs out of the car - that sort of power will tear up the rear with a manual at least. You will get further with an auto, but eventually kill it. Axle housing brace, differential and axles are in order there...

Thank you. Ya I figured the tranny wouldn’t last to long, but I hoped the 8.8 rear end would hold up to some abuse. I have added about 250 lbs in stereo, body parts, tougher suspension parts, and the turbo kit.

Well, I guess I will take one thing at a time, but at least I can prepare for the consequences.

Where might be a good place to buy the crank?
At that power level, would it be better to go with Manley rods? or cobra rods fine?
Is Larry H the man when it comes to building shortblocks? Would i get the same quality going with MMR, Livernoise, etc?

 

[SC boss]

Im glad you started this thread! Im in the market for a motor build also. I talked to Larry this morning after reading so many good things about him. He steered me away from MMR but had nothing bad to say about Livernoise (well at least there heads!) My tough desicion come with price.... For my power goal being around yours, Livernois is a couple of hundred dollars more but claiming 1200hp strength AND comeing with an Aluminum block!! That sounds like a no brainer but its all in what you want, I like to be able to deal with someone one on one to get more info and advice on the situation (And he seemed like a hell of a guy) So after all of this..... I still havent decided completely!!

 

[cekim]

Thank you. Ya I figured the tranny wouldn’t last to long, but I hoped the 8.8 rear end would hold up to some abuse. I have added about 250 lbs in stereo, body parts, tougher suspension parts, and the turbo kit.

Weight is deadly at the track - not only to ET, but the strain of overcoming the inertia of a heavy car if you have good traction, it brutal on the rear and trans.

CHE makes a nice 8.8 axle housing brace that helps a lot. In the 600+ range, I would not expect the stock differential to hold out for very long at the track - tends to start giving you one wheel at a time eventually.

I wish I had an "answer" for what the right thing to do with the 8.8 is, but so far I just bent everything I tried with much less power (and lots of traction). I gave up and went 9" but I am planning on more power

I know others have had more success then I have - so keep asking...

Well, I guess I will take one thing at a time, but at least I can prepare for the consequences.

Yes, and limited traction on the street will be your friend - the street is much kinder than the track as you might imagine, but particularly when it comes to drive-line shock - sticky tires, burnouts and VHT all add up to even a lousy prep'd track is better than your typical oil soaked road...

Where might be a good place to buy the crank?
At that power level, would it be better to go with Manley rods? or cobra rods fine?
Is Larry H the man when it comes to building shortblocks? Would i get the same quality going with MMR, Livernoise, etc?

Engine quality is all about the details - I'd have the builder source the crank for you and walk you through the right parts for your application. Quality is determined by part selection (right part for the right job) and machining quality - uniform and appropriate tolerances for every part that comes into contact with another part... Experience is key - the more engines they have built and the more of "your engine" they have built, the more they are going to know "what works".

I cannot speak for Larry's work, I have never seen it, but I can say for certain he knows a hell of a lot more than I do about building engines so he is a guy worth talking to. I have been pleased so far with livernois' work - head and short block, but I have not really put it to the test yet...

This is not a fast process - even if you have the tools, skills and time to do it yourself. So, take your time, be patient - good people are often busy... and ask all the stupid questions you can think of... Its too late once it is running (or will never run again...)

 

[MikeVistaBlue06]

While we are at it....and not trying to hi-jack the thread, but this would pertain to a new build up...

What is a safe overbore and stroke for the 4.6L block that is stock in our cars?

Stock bore and stroke is: 3.55in x 3.54 in

I don't understand why Ford didn't use a 3.58in x 3.59in setup (bore x stroke) just for old times sake! Hell all we are talking is .030" overbore and .05" stroke!

Mike

 

[Larry_H]

Forge, check your PM's on the other board. The answers to your questions are true, true, and true.

SC boss, Livernois builds a good engine. I give credit where credit is due. However, anyone can claim anything. If you look at the parts they use and then look up the Mfg's specs on those parts, you will see that the mfg's don't claim their parts will hold up to 1200 HP...My motors, Livernois motors, other motors will handle 1200 HP, but I wont make that claim as a statement of strength, because 1200 Hp to this type of rod, it will take it, but maybe not for long. When I claim a particular power level for a motor, it is a claim of sustained power and durability.

Cekim is right...at this power level, things are gonna break...lots of things, depending on what gear you are in when that turbo hits will determine what you are goin to replace first. But suffice it to say that absolutely eveything in the drive train is going to break. There is no stock part on these cars that is designed to take that much stress...

Mike, "safe" is a relative term. Safe for what? an N/A motor you could bore to .030. I would say that for and FI motor and less than 14 psi, that .030 would be OK...more boost than that and I would say that .020 over is the "safe" limit.

Of course, I am talking about a stock block. Darton wet sleeves changes the whole playing field, so does the dry big bore kits.

Why dont we see bigger CID motors? Well, it takes more metal to make a big a bigger motor, there is a cost to that. It takes more effort to reduce emissions, there is a cost to that, they dont get as good a gas mileage, there is a cost to that ...

 

[SC boss]

Thats why I love this forum, you guys know your shit and dont mind shareing info!

 

[ZmanM3]

Very good thread. My thinking though is even if the engine is rated at 1200 HP, if it is going into a daily driven car that is just insane. There comes a point when you have too much power on the streets of the US. If your going to stay around the 700 mark for HP on a daily driver why worry about being able to push 1200 HP out of it? You have the piece of mind to know that your not pushing the limits of your engine so it should hold up reasonable well.

 

[MikeVistaBlue06]

Thanks Larry! Good info. I was quoting that 0.030" x 0.050" extra from Ford so we could have used these on our cars:

http://www.tntmustangconnection.com/item743/image-thumbnail.jpg

So 0.020 is "safe" for the overbore. What about increasing the stroke on a stock block?

Mike

 

[Larry_H]

You can increase the stroke up to 300 inches and still stay with the .020 overbore. You can go to a 302 inch motor if you are willing to go with a .030 overbore.

If you're gonna change badges on a Mustang, this is the one to go with.

 

[Fake_Snake]

i asked what a 427 motor was..

LOL... so what is a 427 .. ive seen one in person with a procharger and custom intake manifold

 

[ZmanM3]

A roush 427R is just a drag racing package that is suppose to put out 427 HP. You can also Stroke (increase the length of the rods) a 351W to 427 but it really only has 425 CI displacement even though it is a 427 stroker. Larry will correct me if I'm wrong but he is the one that told that. Of course if your having Larry build you a 427 stroker and you want to use twisted wedge R heads your going to have to pay 1K for custom pistons, I just decided to go with a 418 stroker and keep the heads.

 

[Larry_H]

The 427 I was thinking of when I posted that badge is the real 427 FE motor.
But, since Matt brought it up....the 351W 427 stroker kit is a good option for Mustangs as well. As I told him, the 427 stroker kits are really 425 CID. You can make them 427 CID by either boring out a 69/70 block to .125 overbore (the later blocks have thinner castings, so that isnt doable) or you can offset grind the crank, use rods with Chevy sized crank ends and get the true 427 CID. I prefer to take the strongest route possible when building a stroker of this size, so any 427 stroker I build will actually have a true size of 425 CID. The options get limited when using the Trick Flow heads. A few years ago, the better quality stroker mfg's were building kits for the Twisted Wedge heads, but at the time, nobody was buying them, so they stopped and dropped the option from their packages. Now, you can either have pistons custom made(expensive) or drop down to the 418 stroker kit. The 418 stroker kit, I am told, uses a actual stock piston for a different application. That is why they are available. So, Matt's Megan will have a blown 281 and Malinda will have a 418 N/A torque monster.

 

[SC boss]

Very good thread. My thinking though is even if the engine is rated at 1200 HP, if it is going into a daily driven car that is just insane. There comes a point when you have too much power on the streets of the US. If your going to stay around the 700 mark for HP on a daily driver why worry about being able to push 1200 HP out of it? You have the piece of mind to know that your not pushing the limits of your engine so it should hold up reasonable well.

The piece of mind means alot to me, I know that its part of the game but $$$ Damn it gets pricey! Once you get the motor capable of holding say a comfortable 700hp you have to upgrade every other part of the car! Thats why its a hobby and I love it!

 

[cobra4548]

So where do you get a 26 spline input shaft for our 5 speed manual transmissions????

 

[killermach1]

I have posted this on other forums, I am new to this one there seem to be many knowledgable people on here. So here goes...At what level of HP should I get a forged bottom end? I am looking at a Kenne Bell 2.6l intercooled kit. which quotes like 471rwhp, or the 2.4l non intercooled kit at 401 rwhp. I would think my stock internals would be good for the 401 rwhp but what about the 471? I want relability and longevity. What are your thoughts?

 

[ZmanM3]

I have posted this on other forums, I am new to this one there seem to be many knowledgable people on here. So here goes...At what level of HP should I get a forged bottom end? I am looking at a Kenne Bell 2.6l intercooled kit. which quotes like 471rwhp, or the 2.4l non intercooled kit at 401 rwhp. I would think my stock internals would be good for the 401 rwhp but what about the 471? I want relability and longevity. What are your thoughts?

Welcome to the site! 401 RWHP you'll be fine, 471 you will probably be fine with the stock internals, really depends on the tune. Then again you can window your engine at 401 with a bad tune. So the bottom line is that if you want to go in that range, or any range for that matter make sure you have a good tune. I'm at 473 RWHP on stock internals but I also have a built engine waiting on me to get back so PMP can put it in.

 

[RedFury]

...absolutely eveything in the drive train is going to break...

Quote of the day, lol.
Great thread.

 

[ZmanM3]

Quote of the day, lol.
Great thread.

Ha ha, good one, and so ture.