kirk35

I'll have to strongly disagree with the stock valve springs being fine for FI. Normally there is a vacuum above the intake valves, when you add 10 psi of boost to an engine you are essentially trying to force the intake valve open. In this case the stock valve diameter is 37 mm or 1.5", using our example of 10 psi this would apply 15 pounds of force against the back side of the valve.

The stock springs are rated at 82# closed and 230# open, by applying 10 psi of boost you have effectively reduced the springs to 67#/215#. Now, would you recommend that someone install weaker than stock valve springs and take the motor to 7k? You may not think you have any valve float, but how do you know you don't? Maybe that power dropping off in the upper RPM's is valve float and not the blower/turbo running out of air.

Ford didn't engineer the stock springs with a little extra cushion in them for FI, they are adequate for a stock engine with a stock rev-limiter, nothing more. I'm sure there is plenty of anecdotal evidence to support your claim, but it is merely anecdotal with no basis in fact.

I stand behind the suggestions I made in my previous post, and wouldn't consider a forced induction system complete without any of the items I suggested.

Simon1

Well Kirk, they are interesting numbers you posted, but the reality is you can search through every major mustang forum on the internet and see what the problems people have in their motors when going FI with S197s. It isn't valve float, broken springs, broken valves or other things related to the springs. The valve train inour cars is good if not excellent.

VCT issues with aftermarket cams, broken pins in the system, bad/broken lifters with aftermarket cams or running incorrect oil has caused issues with the valve train, but not springs.

I do not assume to know what Ford built into their springs and how much they can handle, but from expereince at the track and seeing several hundred people putting blowing on their cars, broken valves or float is not an issue.

I'm sure valves have been broken and failed on our engines, but it is not a problem that warrants replacing springs with any aftermarket part when puttting a blower on a car and running it at levels the great majority of us run our cars at. Put some aftermarket cams in, hell yes. Stiffer valves would be good.

I cannot recall anyone ever having an issue with valve springs.

Sactown ran 13-14 PSI with his TS spinning the motor to 7500 weekly. Hundreds of passes and dyno pulls. No power loss or valve float. The engine lived until a rod went through a block.

To the OP, sorry about the thread hi-jack.

danzcool

That is where the error in your statement is, the stock valve springs are good, you only need better valve springs if you're spinning up the RPM's higher. I think we'd all agree that if your spinning to 7000, you need upgraded valve springs, but if you stay at the stock 6250 RPM rev limit, the stock valve springs will be good, and the block/rods will also last longer.

tx_zstang

I agree, and this guy makes a LOT of good points.

You really want to keep boost low (8 psi or less) so power stays at/under 500; even then, you may overstress the engine and toss a rod or piston (the weak points).

Valve springs are fine on a stock engine with stock cams, those are NOT the weakest points on a stock engine. The only time I've seen a spring failure was with aftermarket cams, and in higher-powered f/i applications.

For fuel system, the recommendation for a GT500 dual pump setup is a much better option than the Ford Racing one you posted a link to, at about the same price. You'll be able to upgrade fuel delivery later if you need it, such as if you build the engine and want to go up to about 700 hp, by simply adding a boost-a-pump. The returnees setup is perfectly fine, when tuned properly.

During this entire process, think ahead. If you do plan on going higher power, you WILL need a forged/built engine, or you will be replacing yours due to a hole in the side of the block. Plan ahead, and if you do intend to go higher power, get parts that you can use (such as appropriate fuel injectors; 39's will be too small).

And definitely get a good tune. There are great tuner people out there who know how to tune these engines/cars with f/i. Do NOT rely on a tune that comes with the kit. In fact, getting a "tuner kit" is usually a better deal for you, but you will have the get the fuel injectors and tuner/tune separately.

A turbo can be a L O T of fun!!! 410's are a little too much, but, fun as ****!
Just do your research, do it right, and you won't have any issues.

Derf00

Spark plugs....dump the stock two piece plugs and go with a one-piece cooler plug for FI...

Autolite HT0 seems to be the brand/plug of choice but I don't know if they are one-piece.

onederful100

FI is always fun.
keep us updated on the progress.

raredesign

Thanks all. I am close to placing the order. I have a performance shop in Buffalo, NY doing the install.
To answer someone's question, I am definitely set on turbo.

I will be putting my stock 3.55 gears back in. The replacement louvers are simply because of a joke shop's bad paint job.

Here is my list so far. At a later time, I will replace the block and internals, but for now this what I plan.
https://www.americanmuscle.com/build...ml?build=97016

Simon1

If you plan on building the block I would do two things in order to save money in the long run and prepare for the future:

1. Skip the 47# injectors and get 60#. You would outgrow the 47# fairly fast if you started pushing the PSI up.

2. Start with a larger turbo. 67 would get you to the power you want to be at.


You will need an intercooler. I did not see one listed in the parts you have shown. If you don't have you'll be sorry.

Water-meth injection is cool and everything, but it is not as reliable as an intercooler and it takes a gifted tuner to make it run correctly. It's just my opinion. I'm sure others feel differently.

Don't take my word for it. Go to S197.com and ask them their opinion. Lots of turbo guys there with tons more expertise than the great majority of people here.

raredesign

Thanks for the feedback. I thought the Hellion tuner kit came with a Hellion Intercooler. Is that not correct?

Simon1

You're welcome. I hope whatever you choose works out well for you and you save money not buying things you don't need. I wasted tons of money partially because I was one of the early guys who got FI fairly early. I could do my tranny swap I desperately need if I still had that cash...