Do exactly that. Keep the stock bottom esp if you want to stay NA. The rotating assembly is lighter than forged components, thus making more power to the ground.

Cams really depend on the rest of the combo. You can get a smaller cam, put the ICL down really low, ie 106 range, and have a nice broad TQ curve that doesn't peak high...even with a edelbrock intake. Or you can get some bigger cams, and retard the ICL back some...in the 115 range, and lose a lot of mid range and low end. But it should pick up more on the top end...is it worth it. Not really, but it sounds really cool at 7200rpm and requires more gear/stall.

I did a W/u on here years ago. Project Proper Centerline....I took a stock Mark bottom and fly cut the pistons myself so I could run a bigger cam AND keep the ICL low for a nice broad TQ curve. It worked really well and was cheap. Just time consuming.

http://www.moddedmustangs.com/forums/99-04/201321-project-proper-centerline.html

 

Im not sure the mark 8 rotating assembly can handle 7200 rpm consistently can it? That sounds sketchy.

 

Mine did. Mine does. My aviator bottom end did in my 4v for years. Itll actually go further. Ive seen 7400 over and over.

 

I'm looking for 6500 tops. I don't want to go to far on a mostly stock T45. That and I really don't want to fly cut. I'm looking for 350ish to the ground, more is better, but is by all means a budget build. I want a ground torque curve, not really high RPM only.


So that leads me into my next question. To dial in the ICL do I need adjustable cam gears?

---------- Post added at 07:00 AM ---------- Previous post was at 06:43 AM ----------

Ok. I read your post. That looks pretty easy. Just time consuming. If I can't find good used cams and end up having to buy new, ill def get the 270s and do this.

Do you know how much you cut out of each?

 

Measure with a mic. Mine were about .120" down from the piston edge.

And no. You don't need adj cam gears. You just grind the key way on the stock cam gears to get it where you want.

 

Keep the teksid and have your crank polished. High reving? Get some good cleviete bearings, preferably the coated ones. Forged I beams would be a good choice for being NA. (MMR 300$) Theyre not much heavier then the stock rods so you shouldnt really notice a power difference. Pistons, I absolutely love the quality of manelys platinum series, allthough DSS, Probe and Diamond make nice stuff. Over all they really didnt weight a whole lot more then the stock stuff.

Make sure you get it balanced, thats absolutely essential. Especially if youre reving up to 6500rpm. A few extra grams off off balanced will chew your bearings. If you do go for the MMR rods they claimed theyre already weight matched but thats pure bs because I had hem balanced and they were all off.

Factory balancing can rev up to 7k+, but if you have the engine balanced by a mahine shop it will climb to 7krpm much smoother and faster. Production balancig isn't bad, but it doesnt comepare to precision.

Now, with stock mark8 pistons and PI heads youre looking at -3cc dish and if I remember right 44cc combustion chamber's. That will leave you sitting around 12:1 compression. Flat tops might set you up to around12.3. While that is a good way to make NA power youre still going to want to run pump has im assuming. Whih is possible but it leaves a lot of power on the table. E85 wouldnt be a bad idea.

And for degreeing cams, save yourself the headache and get the adjustable crank gears. Adjustable cam gears slip sometimes which could potentially mash a ton of valves. Adjustable crank gears are locked into place.

This is just my opinion though.
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Agree with almost everything here...

Your compression numbers are close but off. Using a real calculator that takes everything into account and the correct PI head chamber size of 42cc. LIke I said...just slapping them on a stock mark block with a stock head gasket will net 11.6-11.7:1. Flattops will get you 12.3:1

Adjustable cam gears do suck and I agree. Man...and I can't believe I am saying this...but a customer of mine would not listen and got the COmp gears. I told him to use the stock ones and sell the comp ones. He wouldn't listen. Customer is always right, huh? Well I told him if he has any valvetrain, chain, gear, problems...I am not going to warranty any of it. He agreed. Sucks to say, but his car to this day is still running fine. So...while they may have had problems in the past...their design may be better than before. Granted, I did TQ the heck out of the 6 bolts holding the gears together, and loc-tite the piss out of them...so that may be the trick. Either way...using stock cam gears are the best bet. But like he said. The adjustable crank gears are pretty nitfy for first time users. Only thing that sucks if your gears are off, you have to remove all your degreeing equipment to take the gears off and change them. This is why I like the method of grinding the keyway in the gear to get what you need.

To each his own...just make sure you do it correctly. A poorly degreed motor will never be as fast or make as much average or peak power as a properly degreed motor.

Also...you don't need better bearings than whats in there already. Just leave it and if didn't show any signs of wear, dont even take a cap or main off to look. Run it. I had a 120-130k mark motor in my GT, ran like a raped ape, never even looking into the bottom end. Cut the pistons, put it together and it made damn good power through the auto and saw 7100rpm EVERY single day. The stock bearings are better than most. If I were going to change out to any other bearing, I would ONLY throw a A series bearing in it from Fedreal Mogul. Its a great bearing with a coating and wonderful for the street. I ran these in my TT build, that I daily drove for almost a year, and when I tore the motor down for my BB build, my machine shop asked me if I wanted to re-use them. lol. I told him he was crazy, you can't do that. He showed me the bearings as I was pulling them out, and was like...these aren't even used yet. lol.

---------- Post added at 11:46 PM ---------- Previous post was at 11:39 PM ----------

Why fly cut? How big are the cams?

Id buy rings from CMS. Jim is always cheaper then MMR.

I always use felpros MLS head gaskets. I havent had an issue with them yet. And for staying NA dont bother with arp head studs.

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You want to flycut the pistons so you can install the cams at the proper intake centerline.

---------- Post added at 11:48 PM ---------- Previous post was at 11:46 PM ----------

Planning on comp 270s or similar.

So should I just get a head change kit? Will the bolts be fine for that high of compression?

Bolts are fine. That compression isn't even high...Stock 03/04 Cobras making 800+ use stock bolts...

---------- Post added at 11:54 PM ---------- Previous post was at 11:48 PM ----------

I'll stick with stock bore for now. We only have 91 here. But we're have a pump with 110 race gas. I may do a gallon of 110 to a tank of 91.


Yes I will be cutting my pistons the same way. But I have a 3.8 intake valve which is a little bigger than the 4.6 valve. I already made the end 1/4" I'm going to get a drill bit stop to set the depth I cut to make it the same on each piston.

You will not need to mix any racegas...trust me. I had this same build, with MHS 2s, and when I tuned it, I had to add a LOT of timing to get it to make power. 2Vs like timing and need it to make power. 4Vs, not as much.

---------- Post added at 11:57 PM ---------- Previous post was at 11:54 PM ----------

11.4:1 if I remember correctly.

Great high end power with the right cams, should pull up to 7000, low end torque should be a little better.

If you want, you can always big bore it with sleeves, get yourself 3.7" bores, have an honest 302ci, and close to 400rwhp at the end of the day. The modulars do well with high compression, and you should be ok on 93 octane.

3.7 bore with stock stroke is 304ci...just so you know.

 

I m just going to keep the stock shortblock. I'll fly cut the pistons. I have an intake valve from my V6 that's 1.5mm bigger them the PI valves. I'll use that for the cuts.

I plan to freshen up the short block. Was planning to get the coated clevites. I want to use moly rings. Does the engine come stock with them? If not where to get them?

I will cap the revs at about 6500. But I want my power band to be a bit lower in the range. I'm not shooting for the highest peak power. I want high average power. I hated how my V6 only made power after 3500. But once it got there it was almost like...... Vtec.... Lol

I want power to kick in closer to 2k and it can drop off around 6300-6500. That's the hopes and plans at least.



Do you guys have any preference on head gaskets? I ran Felpro MLS stock replacement on my 3.8. I will get some arp head studs for sure.

 

Why fly cut? How big are the cams?

Id buy rings from CMS. Jim is always cheaper then MMR.

I always use felpros MLS head gaskets. I havent had an issue with them yet. And for staying NA dont bother with arp head studs.

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Planning on comp 270s or similar.

So should I just get a head change kit? Will the bolts be fine for that high of compression?

 

So still like a stage two? You shouldn't need notches if you degree them.

Personally I'd stick with bolts, but I'm only at 10.5:1 compression. The head bolts might give you added security but I don't think you'll need studs for that. Not 100% on that.

 

Read the thread linked in post 2. It talked about the setup I want with fly I cuts.

Compression for this combo comes out a little over 11:1

 

I see, are you cutting them the same way?

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11.4:1 if I remember correctly.

Great high end power with the right cams, should pull up to 7000, low end torque should be a little better.

If you want, you can always big bore it with sleeves, get yourself 3.7" bores, have an honest 302ci, and close to 400rwhp at the end of the day. The modulars do well with high compression, and you should be ok on 93 octane.

 

I'll stick with stock bore for now. We only have 91 here. But we're have a pump with 110 race gas. I may do a gallon of 110 to a tank of 91.


Yes I will be cutting my pistons the same way. But I have a 3.8 intake valve which is a little bigger than the 4.6 valve. I already made the end 1/4" I'm going to get a drill bit stop to set the depth I cut to make it the same on each piston.

 

Ok. I'm tracking with you guy now. I fine with grinding stock gears.. But how much? How do I know? Also is there a good right up (with pictures, I'm very visual) that shows how to degree the engine? I've never had to bother. Slap the cam in and go was the previous method.

 

Im pretty sure MHS has a good write up on their website. If I wasnt on my phone id find it for you.

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Yeah, it is 304.

And I did the math, putting 1gal of 110 in a tank full of 91 octane gets you (assuming 15gal tank) 92.26 octane. You need 3gal of 110 to 12 of 91 to get 94.8, 2 gal gets you 93.5 octane.

 

This I know. But one gallon is fine for summer. (It gets over 100 on a regular basis)

 

Im not far from you bud. Get a 160* Thermostat and you will be fine...

---------- Post added at 08:55 PM ---------- Previous post was at 08:53 PM ----------

hmm tempting that it all switches over. Compression wizzes what would my compression be with a 38cc head? And wonder if id have ptv issues with a cms stage 3 cam and tf heads

Compression with your TF 38cc head will be around 12.5:1. This combo with a nice cam deisgned for it will make for some nice nice numbers. I would expect in the upper 300s easy to the wheels.

---------- Post added at 08:56 PM ---------- Previous post was at 08:55 PM ----------

It will have the same clearance as any other 2v.

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Not entirely true. The TF heads offer a better valve placement and angle when compared to conventional style PI heads. He can get away with a lot more cam with no Valve relief when compared with PI heads. Stage 3 cams will be fine. But you need to degree them and check it.

 

What is needed to make the swap work? Different timing cover? Or does everything from the 2v parts all just swap directly over. Found a cheap mark 8 short block just want to know if I need to outsource any parts

 

PI head and 2v timing cover. It's basically a 2v with an aluminum block and high comp pistons.

 

hmm tempting that it all switches over. Compression wizzes what would my compression be with a 38cc head? And wonder if id have ptv issues with a cms stage 3 cam and tf heads

 

It will have the same clearance as any other 2v.

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160 it is. I was crossed between a 160 or 180. I have a new mishimoto radiator coming to. That should help a lot.

Btw I got my 4v today. I didn't realize how many miles it had. 239k. I will for sure re-ring it. And most likely put new bearings in too. Is there any market for the top end on this thing?

 

Your stock radiator will do fine I was making almost 800hp on a stock cooling system in my 99 GT. If you haven't ordered the radiator yet, dont. put the money else where. Just trying to help.

Yeah. that is a few miles...A ring job wouldn't hurt. Bearings would be fine. Get the A series FM I talked about above.

Top end? Like cams? Heads? Intake?

 

My buddy gave me a cracked mishimoto radiator for free and I managed to get it warrantied. Cost $27 to ship.

Yes top end as in heads intake and cams, and even timing cover. Like is it work anything? I want to trade/sell it for stuff for the build.

 

Ill be running on e85 so might make some good power for a na 2v. Gonna check out the motor today

 

Well FYI. This is why I'm going 4.6.