Any Advantage to Swapping Cams?

[93GreenLX]

I'm rebuilding an N/A motor for my 93 2.3, so I've already got the roller cam. Would there be any advantage to swapping in a mild street cam? Any specific recommendations? I've got a connection that can get me one for about half the price listed on Racer Walsh. I will be gasket matching the intake also and depending on the condition of the walls boring a tenth over. I am decently skilled mechanically and my father in-law (a mechanic for the last 20 years) will be there for support but I mostly want this to be my project. Is there anything I need to change when going to a different cam?

 

[bhuff30]

It depends. You will loose low end torque, but it will pull better on the top end. For a basically stock engine, it won't be a huge advantage to get a cam. A cam will go better with extra compression from milling the head (10:1 is nice ). Best if you have a manual too.
Most of racer walsh's cams are too wild for you. Much over 220int and 220exh @ .050 will be too much.

 

[93GreenLX]

What effects does milling the head to a 10:1 compression on a daily driver? How do you determine the compression ratio?

Also any walkthroughs on ther on port matching the intake manifold? My impression is that the intake manifold does not need to be ported itself besides the port/gasket matching. Am I correct in my assumptions?

 

[bhuff30]

What effects does milling the head to a 10:1 compression on a daily driver? How do you determine the compression ratio?

Also any walkthroughs on ther on port matching the intake manifold? My impression is that the intake manifold does not need to be ported itself besides the port/gasket matching. Am I correct in my assumptions?

Do some research on compression ratios. Dan'l from the board milled his head .060, but that was slightly too much for 87. I think it gave him around 11:1 lol. I ran 10:1 on 87 without a problem.
I havn't matched the gaskets. You'd be better off porting the head.

 

[93GreenLX]

Regardless of what I mill(.020 max I'm thinking) I am going to port match the intake. Will the computer relearn fine with all that extra (woohoo) air?

 

[93GreenLX]

Anyone?

 

[bhuff30]

Regardless of what I mill(.020 max I'm thinking) I am going to port match the intake. Will the computer relearn fine with all that extra (woohoo) air?

Yes, you have an airflow sensor, so it will see the extra flow from the cam and compensate accordingly.

 

[Touring23]

93Green, I have the same engine in my Ranger. I'm using RW's #1 roller which is the same as Ford's A237 and Crane's 199501. Here are some dyno pulls so you can see what to expect:
http://home.earthlink.net/~touring23/TouringHTMLBench.html
Here's a link to a company with a compression calculator and some tech guidelines:
http://kb-silvolite.com/index2.php
The #1 cam idles fine, has ~13" vacuum at idle (sufficient for power brakes), and works extremely well with a 25" tire and 3.73 gearing. In concert with other basic mods (intake, cat back exhaust) you can pick up 1,000 more RPM and it will be much more fun to drive.
Is there anything I need to change when going to a different cam?
YES.
* Collapse each lifter and measure for adequate "preload" after installing the new cam. You might need to either grind the valve stem shorter OR install longer valves, it will depend on how radical you get.
* Install an oil restrictor and/or open up the head's oil drain-back ports. This cam has much larger oiler holes on the lobes and the 8-plug head has shrouded drainback holes. The two facts together cause the valve cover to fill with oil at high RPM. Then this oil drafts through the breather into the intake (!) and it isn't in the pan (!!).
* Insurance: Replace the timing belt.
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Port matching the intake is a breeze. Allow a few hours on two consecutive days to get the hang of it. I didn't touch the port floor, and just slightly the roof. The meat of it will be the sides. I used my electric drill and some rotary rasps from Harbor Freight, worked great and cost less than a Happy Meal.
---
Here's what's planned for this year:
http://home.earthlink.net/~touring23/blocktop.jpg
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Don't stop asking questions 'til you're satisfied.

 

[93GreenLX]

Wow, your site and post we're very infomative, nice to see others who love a nice N/A motor. Between you, Bhuff30 and all the others I'm sure I'll get all my questions answered.

 

[93GreenLX]

http://racerwalsh.zoovy.com/product/RWA1431R Am I correct in assuming this is the one you refer to above. I was dyno'd @ 84 RWHP several months ago before my compression dropped to 91 in Cyl #1 and 120-130 in #2,3,& 4. Did you ever determine the best intake for 91-93 DP setup?

 

[Touring23]

Yup, that's the one.
Wow, your compression's worse than mine. That rebuild should really help you out.
I gave up on the intake swap for now. My dyno software really doesn't care how much the intake flows, since the head's intake port is so poor. I punch in 200 CFM for the intake, it doesn't make much difference when the port peaks out at ~130 CFM.

 

[93GreenLX]

What about a full port for the head then....I thing I don't wan't however is to lose tooooooo much low end torque as it is bad enough already.

84 RWHP BABY!!!!!!!!!

 

[93GreenLX]

I can get the Ford Motorsport version at cost from ford. Anything else to go along with it, that I should get?

 

[Touring23]

Yeah, a port & polish is needed, especially on the intake port; the exhaust port flow (exhaust/intake ratio) is pretty good. P&P'ing this head won't alter the low-end torque that you mentioned. At ~100cc, the intake port isn't exactly large to begin with, and you'll hit water before this port is too large. What's a 302 intake port? 170cc? 200cc? Pfftt. Even after the P&P it will still be an elephant breathing through a soda straw.

In addition to the cam, you'll need the gaskets and seals for the swap. The engine's out, right? Then it's a straight swap. Don't forget the front cam seal

Caution! You will need to address the excess oiling with this cam in this head!!! I'm using an Essy oil restrictor.

If you're worried about low-end, you might like a long-tube header with this cam. My old Hedman made a nice torque peak at ~2900 (see the dyno pulls).

 

[93GreenLX]

Yeah, a port & polish is needed, especially on the intake port; the exhaust port flow (exhaust/intake ratio) is pretty good. P&P'ing this head won't alter the low-end torque that you mentioned. At ~100cc, the intake port isn't exactly large to begin with, and you'll hit water before this port is too large. What's a 302 intake port? 170cc? 200cc? Pfftt. Even after the P&P it will still be an elephant breathing through a soda straw.

So any headwork is pointless, except milling?

In addition to the cam, you'll need the gaskets and seals for the swap. The engine's out, right?

Getting it on Thursday

Don't forget the front cam seal

Caution! You will need to address the excess oiling with this cam in this head!!! I'm using an Essy oil restrictor.

Hmmmmmmmm Didn't know this and can't find any information on it anywhere......

If you're worried about low-end, you might like a long-tube header with this cam. My old Hedman made a nice torque peak at ~2900 (see the dyno pulls).

I've got a Pacesetter longtube No cat and a Flowmaster Delta 40 series 2 chamber. 2 1/2" all the way back

I found a shop about an hour from here that build performance Lima 2.3's on a regular basis. Gonna talk to him next week

 

[bhuff30]

You miss read him... a port and polish is definatly worth while, but unless you can do it yourself, it may cost a little too much.
When I had my NA combo, I was trapping at 75mph with an auto (was 68mph with the stock 90hp). I had slider version of the cam you are looking at, milled head, long tube header with 2.5 exhaust and no cat and a ported intake.

 

[Touring23]

So any headwork is pointless, except milling?

Nah, like Brian said, do the port work. I was trying to tell you not to worry about this:

What about a full port for the head then....I thing I don't wan't however is to lose tooooooo much low end torque as it is bad enough already.

Follow?

(Listen to Brian...help you he can) :yodasmiley:

 

[93GreenLX]

Nah, like Brian said, do the port work. I was trying to tell you not to worry about this:

Follow?

(Listen to Brian...help you he can) :yodasmiley:

I swear I just replied but it's not showing up(past my bedtime) Will a corded dremel with the flex shaft be sufficient? (Wonders aloud if they make a porting kit) I am new to engine building(obviously) and just wanna do it right but also learn, hands on, at the same time.

 

[93GreenLX]

I plan (at this point unless informed otherwise) to port it to match a fel-pro gasket on both intake and exhaust side and blend/taper it down about an inch to an inch and a half. Is this the best approach or could I go further. Remeber I am building this as a daily driver to last me another SEVERAL(12 more would be nice LOL) years.

 

[Touring23]

A Dremel would take, well, SEVERAL(12 more... LOL) years.
And even though you can buy the tools, you still need to know where to grind. Coolant passages jacket the ports; go too far and it's wrecked. My advice is to open the Yellow Pages and start talking with the local shops. You can quickly spot the good shops after a few minutes talking with them.
Start researching the importance of a good basic valve job. A lot can be accomplished in the valve pocket, perhaps more than a gasket match! Picture a valve open .100"; which controls the amount of airflow, the valve or the port throat? The throat only becomes a limiting issue at high lift.
Really, I strongly suggest sending it to a shop.