Switching to a F.A.S.T. intake manifold

[BenKey]

It has been posted on here all that needs to be done to switch to a car type manifold. I'm in the process of switching everything including new fuel rails and fuel pressure regulator.

 

Here is what I have gathered from experience and reading:

 

To switch to a car-type, in this case a 90mm FAST intake and Corvette 90mm throttle body, some things need to be modified dealing with the water pump. For this, there are a few different routes you can go. 1 - you can buy the Speartech idler pulley relocator bracket and change the neck of the truck waterpump. If you have the capability to perform this, or know someone who does, this is definitely the easiest route. It would look like these pics:

You can see how the neck of the pump has been changed. If I remember right, they removed it from the top location on the pump, placed and sealed in a cap to plug the hole, drilled at the location that a f-body would have (forward face of the pump - refer to the below pic and you can see the round boss just below the stock wp neck), placed and sealed it in, then cut a few slices into the inside curvature of the neck, bent the neck to form a 90 degree from the slices made, then welded in the slices. Compared to this pic, you can see how they have cut off the idler pulley and relocated it using the bracket:

 

 

2 - you can get a f-body waterpump and put spacers in and push it out, I think it's 5/8", to line up with the truck accessories. That is the problem with just adding the pump, the pulley won't line up. The spacers for this way have to be cut exactly like your wp gaskets and then you would need two sets of gaskets or 4 gaskets.

 

3 - You can go the way I did. I got a different bracket made by a guy on performancetrucks.net, user name Kano. He did the work and found it was easier for him to go with a '97 vette waterpump that came with a bolt on pulley. His bracket had to be used because the Speartech one was slightly different and not able to be used with this pump. Since the pulley was bolted on, it left an opportunity to add in spacers to push it out. I used a couple of nuts and washers on the 4 bolts to push it 3/4".

Here is a pic of the stock pump:

Here is the vette pump:

In instances 1 and 3, you'll need to slice off the stock idler pulley that is right next to the alternator. This is where the relocation bracket comes in. Using a GM 90mm tb and the lower sitting intake, it would hit the tb. I used a sawsall and hacksaw, but could have been easily done with just a hacksaw and never removed the entire bracket. The metal is pretty soft. Here is what it looks like cut:

Here is the bracket:

You will need to cut the non-threaded potion of the bolt holding it in for it to work. Easy work with a hacksaw.

 

Install everything and this is how it looks all aligned:

 

The new belt size will be 100.5" for the route I took. You may get away with 100", but I couldn't get it on. 101" may be a little too much. Also, if you look at the pump I used (a couple of pics up), you'll see the belt tensioner backet on it - well the bottom of the 3 bolts I had to drill and tap a hole for it. There is a spot on the pump that you can do this that is not drilling where the water is. It's a M10 1.5 thread. Refer to the linked thread below for better pics of this. A spacer will be needed also, as it will sit about 3/8' off of the pump. Measure the length of the bolt before you drill and mark your drill with tape - you can go right into the pump if you are not careful.

 

Once you have done the wp conversion, you can put everything back together and run until you want to tackle the larger job of getting the intake in. It may be a smaller and easier job for all I know. No fabbing required, really. If you do plan to use the stock fueling pieces, some more fabbing may be needed to mount the rails. You can get aftermarket rails for the LS6, not sure about the LS1.

 

 

I would also point you to this thread on performancetrucks.net for more amplifying info. After he posted up his thread, I knew I could do it also. I owe a lot to him (Bill) for helping me get there.

 

Here is how it all ended up:

 

This is a pic of how everything looked after all has been added/connected. The routing of the fuel lines could be done a little different, of course. I chose to do the crossover in the back because the back against the firewall there is not a lot of room to do too much. So I took the supply line, which is the larger of the 2 lines on return type systems and brought it up to the front of the ps fuel rail. That pushes fuel to the back, then through the crossover, to the ds rail, then out to the front of the ds rail, then into one side of the fuel pressure regulator. The return fuel line goes into the bottom of the FPR. The other side of my FPR (black section)is plugged, there is a vent connection on the right side (gold section - this would normally go to a vacuum line on the manifold, if equipped) and the front is where I have a sending unit for my FP gauge inside my truck. On the FPR the black bottom half is where the fuel is regulated and obviously there is fuel in that part. The top half, gold half, there is no fuel in that at all. It is where the big heavy duty spring is to adjust the pressure. Setting up the FPR and adjusting the FP where it was needed was so simple, something I was worried about not knowing much about them, I was like, wow, that's it?

 

 

A better pic of the FPR and the lines coming to it. I don't like how my FP gauge sending unit sticks straight out. I order a 1/8th NPT 90* elbow to make it go down. That is probably the only part I plan to change at this point.

 

 

Just a pic of the crossover.

 

Some of the parts you will need to do it this way:

Purchased here Scoggin Dickey

GM part# 12574221 TAC Module $145.95

GM part# 12570790 90mm TB $299.95

GM part# (will post when I have) 90mm TB seal (I'm using a homemade gasket)

Speartech harness - purchased here Speartech

 

 

I bought my intake seals (set of 8), and the coolant loop from Here. The FAST 90 comes with intake bolts and you do not need the coolant seals. The coolant loop is that little piece of tubing, just in front of your intake manifold. The one I got from Thunder comes out a little further away from the heads and you can re-use the seals. You could get away with just using plugs if you have done a TB coolant loop conversion. I didn't realize that until after the fact, so I used it.

 

As far as the -6AN and braided line stuff I would start here for prices Here?.

I needed:

7 feet of line (that would give a little extra)

4 90* elbows

4 flare unions

2 straight connection (female)

-6AN plug - for my FPR - yours could vary.

If you go to the picture of it all setup, you should be able to see all the connections. I would refer you to this how-to to get your stock fuel lines over to -6AN connections.

 

A few more things to put in. I'll get them in in the next day or so.

[Justin Lamanna]

Looks very nice, I went the similar route with the fast intake I installed as well. Your right, its expensive. with the belt route I took for my supercharger it allowed me to modify my stock water pump and not have to buy a corvette one like you. I guess it depends on your application when it comes time to this. You can also save money buy making your own idler bracket.

 

I'm interested to see how the intake responds to a naturally aspirated truck. I know they work very well on cars. I'm sure you'll keep us updated.

 

[SS_bnoon_SS]

Ben, did you fabricate your own idler pully bracket, or did someone else make it?

[misterp]

Thank you for posting this Ben, very helpful. Can't wait to see how well it works out.

 

Mr. P.

[BenKey]

Ben, did you fabricate your own idler pully bracket, or did someone else make it?

<{POST_SNAPBACK}>

Not me. A guy off of PT.net made it. Read item #3.

[gabbett1]

Ben, did you fabricate your own idler pully bracket, or did someone else make it?

<{POST_SNAPBACK}>

Not me. A guy off of PT.net made it. Read item #3.

<{POST_SNAPBACK}>

 

How much benefit should this have over the stock one, and what would it do for a FI application?

[BenKey]

Ben, did you fabricate your own idler pully bracket, or did someone else make it?

<{POST_SNAPBACK}>

Not me. A guy off of PT.net made it. Read item #3.

<{POST_SNAPBACK}>

 

How much benefit should this have over the stock one, and what would it do for a FI application?

<{POST_SNAPBACK}>

This is how I look at it. Guys switching over what their f-bodies came with usually make around 20 more hp. Truck guys switching to car intakes usually net around 20hp. So, I think since I am going from the truck intake to this one I should come close to netting around 40hp. That may be a little generous and will depend greatly in how high I spin it, which right now is 6500 and don't plan to go any higher.

 

Turbos or centrifugals would benefit from this as well, but it may or may not be as great an improvement since you are already forcing the air in. This intake will force it at a much higher velocity though, which would mean more power. Again, probably has a great deal to do with how high you're spinning it.

[BenKey]

Anyone have experience with braided fuel line and putting on connectors? I knew it wouldn't be the most pleasant experience, but didn't realize how much of a PITA these things are.

[SuperSport]

Thanks for starting this thread Ben, I am sure this is going to be one of the best do it yourself articles after your done

[gixxerrider]

I have done some aircraft high pressure lines. its a pain in the a$$

[BenKey]

Progress:

 

I'll probably finish up tomorrow. Just need to decide where to mount my FPR and route fuel lines accordingly. I'll post up details later.

[gixxerrider]

Looks good. When do you want to do mine? HAHA

[BenKey]

Looks good. When do you want to do mine?      HAHA   

<{POST_SNAPBACK}>

I would certainly "help" you do yours. Except the buying part.

[sandmanss]

If it performs as well as it looks your in for some performance!

[04CHASE]

looking good ben . glad to see your getting closer to having the ss driving!