Power options for older Glastron

[modela]

I have a 1974 Glastron in very good shape that I am updating the engine on. It had a 302 Ford V-8 with 351 heads (factory stock). Attached pictures show old Ford 302 and Mercruiser EFI components, and the new explorer engine. I am putting in a new explorer 302 engine. The engine is a long block including water pump, lower efi manifold, valve covers, oil pan, etc.

I would like to upgrade the fuel system. I thought about putting in efi and picked up a Mercruiser efi system but it looks quite complicated. Is this feasible or would I be better off with a good carburetion setup.

Right now it has a Holley 450 CFM carburetor.

I would like recommendations on completing my project

Thanks,

Jim

[gonzo]

If the engine came out of an Ford Explorer, you'll need to at least change the camshaft ot it will disapoint you. The low end torque will be poor for the application.

[modela]

I thought the cam might be a problem. Do you have any suggestions for brand name? I picked up some roller tappets to go with it.

Thanks,

Jim

[Jango]

The Stock Ford Roller cam used in 95 -2000 Explorers (pt no. F4TE-6250-BA)is a GREAT TORQUE cam for marine use. Used in a Stock 302 marine(5.0) with stock center rise exhaust manifolds, torque will be 300 lb-ft @ 2000 rpm to a max of 340 around 3500 rpm.

Unless the engine is highly modified for sustained use over 5000 rpm, this is the cam to use.

[modela]

This engine is a crate engine so I assume it would have the stock cam.

I am trying to fit it with fuel injection and so have acquired most of the components for a 1993 OMC efi including fuel rails, ecu, wiring harness, low pressure pump, and throttle body. I am missing the upper manifold and the high pressure pump. From what I have found out so far there was a water cooled reservoir/high pressure pump setup that was subsequently replaced by a water cooled fuel heat exchanger. I have a good EFI OMC manual but there is still a lot left out.

Thanks,

Jim Marshall

[Jango]

If it is truly a late model Explorer Crate Engine and it has a roller cam, most likely it will have the "High Torque Explorer cam".

Can't help you much with the Fuel injection other than, the Standard Explorer system is Equiv. to a 500 cfm. carb.

Good luck on your project. Jango

[modela]

Thanks for the help. I think that it is. It has GT40 heads and everything is brand new (not a rebuild). Do you know what the HP is on the explorer engine? I realize that torque is the number one thing in boats but I am curious for comparison to my older 200 hp non-roller carbureted 302.

Jim

[Jango]

I believe the 302HO Explorer Engine was rated at 210HP (single Exhaust & mufflers). For marine use, with center rise exhaust manifolds it should be at least 10% Higher, 230HP plus. I don't believe GT40 heads were Std and will add another 5 - 10%.

Keep in mind, Speed predictions based on HP change is expodential. A 25% increase in HP is only good for a 12% increase in speed. (everything else being equal - weight etc.)

[modela]

Jango,

I guess what my goal is what is called "retro-mod" or bringing an older unit more up to date. I like the idea of fuel injection, roller camshaft, and other improvements. I don't need a great deal of improvements because I was satisfied with the boat before.

In comparison of the exhaust ports on the newer heads they are a fair amount bigger.

You mentioned the center rise exhaust manifolds. Have you or anyone seen manifolds like the Glastron ones pictured and have any idea how these would behave?

Thanks,


Jim

[Jango]

The Glastron manifolds are very similar to the Mercruiser Log Type. Not as efficient as the center rise type, but "Usable". If your manifold has enough material around the Individual exhaust ports, It would be a good idea to grind material and try to "match" the Head ports, thereby minimizing exhaust reversion. Left "As is" the manifolds will tend to "choke" the motor resulting in loss of power at the very least.

[modela]

Thanks for the information. Would you recommend any brand of replacements? I see quite a few listed on ebay, etc.

Jim

[Jango]

I'm told these are Good, but not sure if price is for one side or the pair. They will however require extensive plumbing changes.

Ebay# 310006333001

Since you are more interested in a "Resto-Mod" and not max. performance, I would stay with your Glastron manifolds after "Opening up" the exhaust ports as much as posible. If you are unable to Fully open, taper the opening for a 1/4 in. or so to the Head Port size.

Hope this helps, Jango

[modela]

I will do that. I have a die grinder and will work off the manifold gasket and see what I can do from there.

Thanks,

Jim

[gonzo]

Jango: I am curious about the specs of the Explorer camshaft. Did they install the "tow truck" package type? That is about identical with the marine version.

[modela]

I have looked high and low on the internet to try to find out more about the specifications of the Explorer 5.0 engine. It would be nice to know things like the torque curves, injector size, throttle body size, etc.

Jim

[Jango]

Gonzo,
As I understand it, the Explorer(High Torque) HO cam was developed in the late 1990,s for use in the Ford Explorer only.
Specs are:

Valve Lift .422 I , .448 E

Specs @ .050 lift

IVO -25 deg BTDC, IVC 31 deg ABDC Duration 186 deg

EVO 32 deg BBDC, EVC -15 deg ATDC Duration 197 deg

Lobe Centers 115.8 deg, Valve overlap -40 deg.

Jim,
I see no reason why you couldn't use the STD. 5.0 Truck injection, which, by the way is larger than the std Mustang or Full sized Car.

I purchased a "New" 2000, 5.0 Block and installed the Explorer cam, together with Windsor Jr Heads and a 750CFM Edelbrock Carb.*
Engine produced over 300HP and over 350 lb-ft Torque from 1500 - 4500rpm. I have since "opened " the 302 to 327 cu in, added Alum Hds and a Trick Flow Stage One cam with Execellent results. See:

http://www.glen-l.com/weblettr/webletters-11/webletter94.html#monaco

John (jango)

* 5.0 Fords "like" alot of carburation

[modela]

John,

Thanks so much for the information. I have been pouring through the EFI manual for an OMC which uses the same manifold. From what I can tell they do not use the exhaust sensors due to the cooled manifolds. I know you can get heated sensors but am not sure that would work out so well.

In addition there does not appear to be a egr setup on the EFI. Otherwise it looks pretty much like an explorer or cobra manifold setup. I have rounded up most of the components including all of the harnesses, manifold, etc. but am still looking for some odds and ends. If all else fails I will go back to carburetion.

I looked at your site and there are some really nice wood boats. Years ago I thought about building a wood boat and got some catalogs from Glen-L. With too little time back then I gave it up and bought a fiberglass.

Jim

[Jango]

Jim,
Here is some basic specs for the Explorer ( rear wheel HP & torque w. single exhaust and muffler)

http://www.kbb.com/KBB/UsedCars/Specifications.aspx?SelectedTabIndex=1&ManufacturerId=15&YearId=1999&VehicleClass=UsedCar&VehicleId=5436&PriceType=Trade-In&ModelId=100&Mileage=75999&SelectionHistory=5436%7c9976%7c26101%7c100%7c10%7c207730%7ctrue%7c207771%7ctrue%7c207748%7ctrue&Condition=Excellent

John

[modela]

John,

You really seem to have cranked a lot out of your engine. I have a few questions for you.

My engine seems to be similar to your first engine in that it has the explorer bottom end and cam. It has GT40 heads versus your Windsor Jr. Heads and is carbureted. My baseline engine was the existing Glastron with 351 heads that was listed at 200 hp (hard to tell about torque).

What can I expect out of the new engine compared to the old? I saw that the new engine was rated at 210 hp. What am I getting out of a roller cam and the GT40 Heads?

What is the best way to accomplish more hp say with roller rockers, a new cam, carburetion, etc.? What is a good rpm range to run in for a stern drive with probably a heavier boat than yours? How much lift can you get on a new cam without getting into trouble with standard pistons?

I am probably not going to go much beyond the given Explorer bottom end and heads.

Thanks,

Jim

[Jango]

Jim,

As previously stated, you,re probably looking at abt. 240HP. The GT40 Heads, while better than Std 302 do Not have the Port flow numbers of the Windsor Jr, nor as Big Intake and Exhaust Valves as well as comp Ratio. The Alum Heads,i.e. Pro Comp 190 -210, would be the next level up after the Windsor, . A 750CFM Carb is good for 10-15 Hp over 500CFM (Carb or F.I.)However 310 - 320 HP and 5000 - 5500 RPM is max for the Explorer cam.

Roller Rockers are better, lower Friction w. probably 5+ HP. You can probably go to around .500 valve lift. But this should always be checked with modeling clay.

You need to be careful with Cam selection, because of Low RPM Torque requirement in Boats. I would run your Engine at 240 HP peak, at 4800 - 5000RPM max.with minimal load (Driver & Half tank of Fuel)

Hope this Helps, John

[modela]

John,

Helps a lot. I will play this one out and see how it goes. If I get bored you gave me some ideas on where next to go on the engine. I will port the exhaust and if that seems to be a problem I might get new manifolds.

Do you run a fresh water heat exchanger system on yours?

Jim

[Jango]

No Heat Exchanger - Fresh water use Only (Ohio River and occasional Lake)

[Jango]

Jim,

Got some additional Data on your Motor. If your Motor is a 1997 1/2 or later it will have the GT40P Heads.

HP/Torque with the Center Rise Exhaust Manifolds = 270 with Excellent torque of 340lb-ft @ 2000 to a max of 360 @ 3500. Looks like HP is probably about 250 w. Ported Glastron manifolds with only a 10 lb-ft decrease in Torque.

To see Head Data, clic on:

http://www.stangpro.com/html/articles/gt40p_files/gt40p1.htm

Although the HP Numbers are LESS than the Windsor Jr Heads, the Torque numbers are almost IDENTICAL.

John

[modela]

John,

Wow, that is more than I expected. Thanks for the information. I noticed that the exhaust ports were quite a bit bigger than the 351 heads on my old one. If I want to get a little more hp out of it I can put on the Center Rise Manifolds.

I was talking with the fellow that I bought the fuel injection parts from and he said that the OMC version was rated at 275 hp at the prop. Sounded to good to be true, but who knows.

Thanks,

Jim

[Jango]

Jim,

My numbers are not an Estimate or a guess. After finding the Head no's, i.e Flow, combustion size, valves,etc, together with cam data and intake (sequential flow injection) the Data was entered into "Dyno" software for the stated results, which, by the way, should be very accurate based on my Engines comparisons to actual output.

Since the Glastron manifold is an an unknown, that output will be an estimate.

John

[modela]

John,

Well, considering I would have been happy to pick up 20 to 30 hp, I think that I will be quite happy. Still working on the efi system and getting components together.

Jim

[Jango]

Jim,

If you decide you want more, a cam change would be far more effective, both cost and output than larger Heads. Larger heads will of course add more power,but at a substantial cost.
*A "Trick Flow Stage One" cam will add abt. 65 more HP (335) and 30 lb-ft torque (390max) without losing bottom end power. See:
http://store.summitracing.com/partdetail.asp?part=TFS%2D51402000&autoview=sku

Keep in mind ANY cam you use,CAM timing should be set at -4 deg. Also be sure to check piston clearance with larger cam.

* Output with GT40P Heads

[modela]

John,

Is this the one you used in your boat? It does add the Hp and torque. Did you notice a low-end torque loss?

Is there any way except clay to tell what the piston clearance is. Pulling the head seems like quite a bit of trouble.

It is interesting to find out about those things from your experience.

Thanks again,

Jim

[Jango]

Jim,

Yes, this is the cam I am using. Smooth Idle and lots of Torque, 400 lb-ft between 2000 and 6000 rpm, with a max of 460 at 4500. The Explorer cam produced the same 400lb-ft with a max of "only" 415 at 3500. The "Low" max. is partly due to the Large Ports in my Heads (Pro Comp 210 Alum.)

A 302 with GT40P heads will have the same (as Explorer cam)340LB-FT at 2000 to a max of 390 at 3500 rpm.

Unfortunately, I know of NO other way to check Piston/valve clearance, but to put clay on piston top and reinstall Head, rotate crankshaft (2 revolutions by hand), remove and measure compressed clay. You might contact some Mustang owners who use this Cam (GOOGLE??)

[modela]

John,

It has been quite a while since I pulled down and rebuilt an engine and hence I have a bit of stage fright. I look at this new crate engine and think, "Am I going to screw it up?" I have a set of roller tappets to install but I am also wondering about push rod length, setup, etc.

Sounds like you are more confident and readily make changes with yours. I hope to get to that level.

I guess I will have to get rid of the butterflies and go forward. It has been a long time since I ran the old 302 carbureted Ford, but I think that the top end full throttle of the boat was about 46 mph with about 4600 rpm. I believe it was running a 15 x 19 prop. It had plenty of power on the lower end.

If it develops that much torque I might have to go to a higher pitch prop but that is down the road a ways.


Jim

[Jango]

Increased Torque has more to do with Acceleration than Prop Pitch change.

If you were able to do 46 with 200 HP, You'll get to about 53 with 270HP or 60 with 335 HP.

53 mph just means Higher rpm with same Prop. 60 mph, probably more pitch.

[modela]

John,

It is nice to be able to see what you have done and how it worked out right down to the cam selection. Someone earlier in another forum suggested I change to a 351 for what they called "legitimate horsepower" probably relating to the increase in torque that the stroke provides. Out of curiosity why did you stick with the 302? I did because I didn't want to increase weight and complexity.

It will be interesting to see what the performance ends up. I can say that this has been a very interesting project and a good learning experience for me. The fuel injection has also had its challenges and I have rounded up most of the components needed.

I figure that I can always drop back to carburetion if I have to.

Jim

[tuantom]

I'm a little confused as to how only a cam change can gain over a 100 lb-ft of torque in a 302. Seems a bit optimistic. Those would be big torque numbers for a 351.

[Jango]

Jim,

You're correct about increased Torque with Added Stroke. I went halfway there with my Engine, 3.25 Stroke (327cu in). Could have gone "All the Way" to 342 or 347 cu in. Since increase would have resulted in only 20 ft-lb (NO Change in HP)with undesireable Ring Location over Wrist Pin, I decided the 3.25 Stroke was optimum for the 302 block.

The 351 is Heavier and Taller requiring changes to my Boat which I didn't want to do.
Besides It's a lot of Fun "Blowing Past" the 350 Crowd.

A Whole Lot More than a Cam change accounts for my numbers, which are varified. As stated earlier, In a 302, Cam change alone accounts for only a 30 Ft-Lb change in Torque. Keep in mind, these are "NOT Rear Wheel Numbers", but At the Flywheel.

[modela]

John,

I read about some of that in a stroked 302 book about the rings being over the wrist pin. The books states that in stroking that you will shorten the engine life and also was not encouraging about rings over the wrist pin. I think that they were saying that stock engines are really aimed at longevity and reliability to the detriment of performance. Having the rings over the wrist pin does sound a bit weird or at least stretching it. Have you done quite a bit of this kind of work in the past?

I am still accumulating parts (I am going to need a 50 oz flywheel) for the new engine and getting my shop organized at present.

Have a happy holiday season.

Jim

[Jango]

Jim,

Adding Power has the potential for shortening Engine Life, Stroked or Stock. My Motor is run less than 50 Hrs/ year. Yes, I have been rebuilding Engines on and off, for some time. In the last 15 - 20 years, probably have Done 15 or more Ford Engines, 289s, 302s (mostly) and 351s, both W and C engines.

My Engine uses a 5.315 in. Connecting Rod rather than 5.400 in. in order to keep the Wrist Pin away from the Lower Ring.
The rotating assem. Has been Balanced to within 2 grams and uses a 28 OZ. External Balance.

I have to disagree with The statements about performance, 302,s are an Excellent Motor in Stock Displacement as well as modified displacement. Don't know much about the New Over Hd Cam motors, but the 302 block can produce More HP/Torque per cu.in than Anything Ford Produced.
( A 347 cu in, 5.0, with the same cam etc. will produce more power than a 351W)

A very Merry Christmas to You Jim