First a very brief response because you listed them so well and you seem to be putting a lot of thought into the rebuild. This is a subject that has had a lot of coverage and there is lots of info in the archives, but I think we cannot stess enough NOT to go overboard with an engine build. Especially to make the kind of power you have indicated.
· Balance $130 YES
· High Vol Oil pump $18 NO
· Adj Cam sprocket $46 NO
· Better Head gasket $19 YES but only Fel-Pro wire ring (#1035 about $60)
· Face flywheel $35 YES
· High strength fasteners $80 NOT NECESSARY @ $250
· Bronze valve guides $50 NO
· Lightened Flywheel $55 NO
· Match manifolds/head $50 NO
· Port head $100 YES
· Roller Cam $348 NO
My intention with this engine is for it to last 100K miles and probably get to around 250 HP once I get the better exhaust, Intercooler, 3"downpipe, and maybe a mild chip in place, and not spend a ton of money.
You can make 250 HP with a basically stock engine with lots of boost and good intercooling. Everything stock with mild modifications. Some details......this is very similar to an engine I am helping with in the Detroit area for an SVO Must. Objective, 271 HP (same as 289 HiPo)
Hi volume oil pump is not necessary. The stock pump is about the same flow as a 460 V8. (No data....your gonna have to trust me on this one) Going to hi volume only puts more stress on the auxillary shaft and this is the big weakness in our 2.3.....If you want to increase bearing clearances and use oil flow for cooling, then you need more capacity, and Esslinger has a really nice heavy duty Aux shaft with distributor gear, and hi volume pump. but again, if the bottom end is stock and power is below 300 dont worry, be happy..........you have a really strong structure.
Adjustable cam sprockets look great, but if you don't have to cut more than .010" from each surface, it is not really necessary. But cheap enough that if you really want it why not.
Better head gasket. Everyone does not agree, but the Fel-Pro wire ring gasket, while not cheap is the very best that money can buy for the 2.3. I know Nick likes one of the Detroit gaskets, but they do NOT have the wire ring and CANNOT provide the same combustion sealing "unit load". This is the same gasket I had installed when we went 11.53 ET and the same motor, head, and gasket went 186 MPH at Bville.
Studs and nuts help a lot, but at the levels you are talking, they are not necessary. Nice, but not necessary. If you have the money budgeted, go ahead. Use the studs that neck down. These provide more recovery and less of a necessity to retorque. I do not use these but then I have retorqued heads regularly when using gaskets.
Bronze valve guides have proven to be as much problem as anything else. If you do not have excessive valve guide clearance, do nothing. Use the NOK valve stem seals (production 87/88) and a little more exhaust clearance than intake (they run a LOT hotter) The problem with bronze is that some alloys will shrink with high temperatures experienced under Highly boosted conditions. I run a lot hotter than most, and have had exhaust guides sieze the valves so they had to be driven out. No damage to either valve or guide, but the size permanently became smaller. If you must put guides in the engine, ask again, because there are some alloys that will be affected less. I cannot remember which alloys and need to go into my own archives and I'm running out of time today.
Lightening flywheel is debatable. Most of us feel that the mass of the production wheel helps the launch of our relatively heavy cars. The aluminum wheel provides a better transient response, but also have a tendancy to vibrate loose unless driven with pins in addition to the 6 bolts. The problem I have is the original wheel was engineered and tested to not fail at speed much in excess of what you can run at on one of our engines. By machining away material you will create a component that may behave in an unpredictable manner. If you must have a light weight wheel, buy a light weight steel wheel or go to an aluminum. I would not run a modified cast Iron wheel in my worst enemy's car.................(well maybe one guy)...........
PORT head................YESYESYESYES..........and the intake upper & lower The valve throat and valve pocket respond very nicely to a little massaging. Keep stock valves, (the exhausts are inconnel) (and yes you do need them for durability), port, modify the chamber for more volume, extending the chamber toward the exhaust side thereby making the spark plug more centrally located. (Not much but a little helps.)
Save money where you can and spend it on the best air charge cooler that you can find and the 3" exhaust system. Nicks pipe and intercooler are probably the single biggest improvement you can do. The engine probably has to be redone, but be conservative with the engine modifications. You can make the power with the stock valves and cam. If you need to change a cam, one that most on the list have overlooked is the Lunatti .500" lift that used the stock events. This is not a roller cam, but is hydraulic and when installed with the correct valve tip heights works well. It idles and is streetable. As with almost all aftermarket cams, we loose bottom end and somewhere in your plans should be a lower ratio rear axle. It really makes the package wake up and makes it feel like a super car.
I hope this helps.......................its just a small consideration.
Do not go overboard, and remember that air flow, boost pressure, and air charge cooling are the main things to work with.
Nick (Modern Performance)
Subject: Re: Ideal boost curve
When our motors make peak torque will depend more what is done to the motor. The stock XR motor and turbo will peak around 3800. The T-bird IHI turbo will peak lower. A motor with work done to it and the stock turbo can pull peak torque as low as 3200. Check out the dyno numbers on Jon's car. It made peak torque, around 270 at the rear wheels at 3200. Boost spike feels real good but it can cost you a head gasket. If you lower pressure drop in the intake system and cylinder head along with lower back pressure on the exhaust side, you will build more torque at a lower rpm. This is one reason why I feel you should not gut the upper manifold and hog out the intake ports.
Turbo and camshafts will also help or hurt your lowend torque. Most people over cam and over turbo. 2.3 turbo motors that make more topend power have at times gone slower in the 1/4 mile then motors making a lot less. Turbo exhaust housings, turbo trims and camshaft duration's are very important. It is better to stay mild the wild. Thanks again
After playing with my new cam grinds, cam replacement moves
higher up on my preferred mods list, sorted on money spent and
5=intercooler (purchased, not fabricated)
Somewhere amongst all that falls ported exhaust/intake manifolds,
and other mods.
In a message dated 98-03-26 00:40:53 EST, you write:
· Can you tell me where I can get this cam?
· Is there a wear problem due to the high lift and
· non-roller configuration?
· Lunatti Cams in Tenn. I do not have a number but they advertise in most publications. Hot rod, Street Rodder etc..... Russ Harness at Rapido also has carried them in the past. I think Esslinger may have them in stock also. The deal is do not accept a substitute. As has been said in the past, this deal wants to be as little overlap as possible. Lots of lift but otherwise pretty mild and conservative. Slider followers are not new, and they are really not bad. They are just not as good as the rollers we have now. The key to long life is the iron alloy and the heat treatment the finished cam goes thru for hardness. I suspect that the aftermarket is a little sloppy about alloys and heat treat. Very cost driven, and heat treat is hard to control. The roller cams are almost all billet or powdered metal and hardness is easier to control. Actually we tried nodular cams for rollers when we did the first one for the 2.3 and ended up with the powdered metal (more expensive) because of a few failures.
If you assemble a slider follwer cam with all new components and keep the springs conservative. You don't need 400# @.500" but thats another story...No actually its an important part of this one. Most of us choose springs that are too heavy. With the engine calibrations we use and fuel shut off being at 6250 or if a chip I'll bet no one runs higher than 7500 RPM, we dont need super heavy springs, especially with stock valves. (would you believe that Esslinger now runs the midget motors over 10,000 RPM (and they live)). Dwaine really does understand the geometry of this valve train............. At any rate, use lots of MDS lube (the ugly black stuff) in assembly and break in like Jon Welsh described in the archives. (20 Min at 2000 RPM) dump the oil, filter, fill it up with fresh good oil, the slipperier the better, and take off. (I use Mobil 1) The used cam I sold a guy had 65 1/4 mile passes and 2 years at Bonneville on it. (about 16 passes)(2 records) 186 MPH fastest, and it looked good. Speed limited to 7500. The cam is all done at 7000 anyways. I know a number of guys that ran this on the street, and were happy. Consider though that some bottom end is lost and the gear I mentioned earlier is a good idea. Powertrain matching is soo neat............. and we all overlook it at one time or another......
In my opinion, my perfect street package will be, (and I plan on doing this some day).
Killer street response, but not much top end because of the exhaust back pressure caused by the little t2 housing. A 4.57:1 or 4.88:1 rear, with a .90 overdrive ratio T5 transmission. This will make a killer cruising street package that will be a blast to drive in the city BUT will not necessarily be fun to drive on a long trip. Typically, we do not take our "fun" car on long trips cept maybe Carlisle, but then ear plugs are cheap. My point really is that we do the things to lose bottom end, but do not make other adjustments because we think its too radical. A 4.10 rear is no more radical than a super 60 or a T4 compressor. We must build an integrated package with all the parts complimenting each other rather.