Engine and Transmission Tech

First a few words, I just recently rebuilt my very first engine a 4.0 with some mods for my 2 door RRC. Please understand that this is a hobby for me and I just started to discover what a challenge rebuilding is all about and of course I just cannot describe the joys of seeing your first build actually burbling to life..

Well I have a chance of getting my hands on a Triumph 1500 , but I am actually looking for a way to build my second V8, but this time I want to build something a bit more unique.

Having drooled over "Hardcastles V8 Tuning" book, I have a pretty good idea for the build, however if I may impose I would need some help with this project.

I have another 4.0 block unknown origin, which I will dismantle for this project.

This will be a relative high RPM tune, given the aplication.
I am still in the process of getting things planned out for this project, but the general direction is a girdled bottom end, a Buick 300 crank (3.36" stroke with a 3.70" bore) with Ford 2.3 litre Turbo pistons on 2.00" Chevy rods for a 5 litre of displacement (taken from Hardcastle's book).

Now for valve train and heads, I am a struggling! One I would like to stay with hydraulic lifters, but would like to bring the RPM range to the mid 6k range.

Thats what I have so far, any comments, suggestions are welcomed.

Thanks

./RB

Hey man. Welcome. I totally dig your enthusiasm, and it brings back memories of when I got started on this path. Good times.

Ok the tough part with the Ford piston thing is there isn't enough liner to use them reliably since they are 3.78" bore. Even after sleeving it's pretty tight but may be possible if you want to risk it. I'd feel confident with the 305 bore though (3.736"). Lot's of options for pistons there too. I went with 60 over Ford 255 pistons (3.74"). Not really recommending that option. Lots of modification needed there if you want a bigger cam which it sounds like you do. I sorta wish I'd gone with the 305 route.

On that note one thing to watch for is the block's current deckheight. It turned out my block had been worked already and I ended up with pistons out the top. LOL! The other thing is CC the heads early. I discovered my Buick 300 heads were 45cc instead of the stock 54cc. WOW big surprise there it kinda changed everything about the build. That coupled with the positive piston deck of about 35 thou and I'm now running 12.5:1 compression and likely E85.

I'm thinking you are going to want to sleeve the block. Are you in the US? The US 4.0 blocks do some cracking behind the liners because of a high-temp thermostat that Rover put in to comply with emissions standards. They are almost always cracked because of this but it's possible that yours aren't. It's sorta worth doing it and you get more margin for bigger bores. It's not cheap. Just something to think about there.

You ARE going to want to do some oiling modifications. The main pick up in the block needs to be enlarged to 9/16" or 5/8" with a later larger bore pick up like a late Buick v6. Just be sure to measure it when you take the engine down. It may already be large. Mine was. I'm not sure if 5/8" is standard on the late blocks but it was on mine. NICE. The other oiling mods are optional but can't hurt: Have the cam bearings spun 180º and cut smaller holes in all but the gallery transfer bearing. I cut my holes at 1/16". The cams in these engines get plenty of oil and as the bearings wear over time become a massive hemorrhage of oil reducing the oil to the mains. The other place to limit is the rocker shafts. I converted my engine to oiling the rocker through the pushrods instead of the heads. This is another place the oil pressure is reduced as time goes on. The point is to keep as much oil going to the mains and journals as possible.

I got these mods from another book that's worth reading: How to Power Tune Rover V-8 for Road & Track
[www.amazon.com]

I think an absolute must-have for higher RPM is the rocker gussets that D&D sells. Especially at higher RPM the rocker shaft ends can set up a harmonic and break.

Lastly, look into a cam optimized for your application early and stick to it. That effects EVERYTHING. I changed my mind midway through and did almost everything over. I guess what I'm saying is have fun with the planning part. Plot a clear course and stick to it like a religion. You will save a lot of money.

I'll also suggest spending the extra money and balancing the engine, and having the parts blueprinted to eachother. There is some easy power and longevity to be had there. I did that and I'm hoping it helps my engine last a while. As it is I'm probably going to frag my pistons with in a week and do this whole thing over. LOL! Seriously, I hope I don't break something.

Thank you for your response!

This is just a great board...

Ok so lets start with the piston choice!

Firstly I will be resleeving the block and with top hats. I found a nice shop who has the appropriate CNC machining to do this work. Now in the selection of sleeves . Can i choose a sleeve that will give me the 3.736 bore, or do I need to remove material from the block (which I would not want to do)!

As for heads I do not have any heads, maybe looking at a complete set !

You are quite correct about choosing a cam early in the planning phase, but I fear that I lack the skills in selecting the right cam. I do want a very streetable engine with a nice torque curve, though a bit higher in the rpm range.

The block main pickup was at 5/8 on my first rebuild , but I will check it.

What do you think of a girdle with the main caps integrated ? Would this not give you a bomb proof bottom end.

BTW the project is called "Mongoose" a Cobra killer ;)

First thing RB, and most important to do right away is, don't get in a hurry. Make sure you clearly understand your goals and options before you start. Now having said that, at some point you have to draw a line in the sand and begin buying parts. Nic, myself, and many others know full well that once you begin the build other options appear that you hadn't considered and may cause some regrets but don't let that deter you. Once you've drawn that line do your best to stay with it.

So, while a screaming high rpm motor is great, have you considered increased displacement as an alternative? For a measly extra 80 lbs of engine weight you can go up to 300, 340 or 350cu.in with an inexpensive build, stay under 400 lbs and crank out 300+hp all day long with great reliability and economy. No messing with sleeves, stroker cranks and all that, just the right match of stock parts. Check out the threads on 300's, 340's, TA heads, etc. Now for high speed, if you can afford it nothing is going to touch the new TA heads but they aren't cheap. Also, roller cams are the coming thing. For very high power potential we have the Buick 350/TA/roller cam build on the horizon. Things are happening pretty fast right now so you really want to get caught up before drawing that line. Finally, on your redline, a decent cam with the right springs *can* actually net you a 7 grand redline, provided the rest of the engine is up to it. That means forged pistons, maybe some rod work, studs, and definitely the oiling mods. Get a set of TA's double groove cam bearings, port the oil pump passages, and carefully set the pump gear end clearances. Watch your bearing clearances and keep them tight and true.

Jim

I was actually going to suggest the TA heads after reading Jim's post in the TA head topic. If I had not done all the work I did to my old 300 heads I'd be buying those in a second. They look frickin' awesome.

On the cam I'd call Woody at the Wedge Shop. He's got TONs of experience with Buick/Rover strokers. The cam I'm using may be what you're looking for. Streetable with a raised powerband.

[www.thewedgeshop.com]

Wow! Great stuff!

Blown MG the reason why I selected the 4.0 V8 is because I did my first rebuild on that block and I am more comfortable with this block and some of its components. Unfortunately I know nothing of the 300, 340 or 350.

Though I am very intriqued by what you wrote. I just hope that I can find project where I may dwell on these blocks...

NixVega, BTW I had a 73 Vega. Tons of fun with them, though they rusted out badly in Montreal's winters. Its funny because everytime I stopped for gas, I would fill up the oil and put a quart of fuel in ;)

Good memories!!!

I will certainly get in touch with Woody.

Again thanks

Here is a picture of the intake and carbs;)


Guess where I first saw this :)



Edited 1 time(s). Last edit at 10/26/2009 02:01PM by Roverboy.

Motorhead porn.

Rino,

Additional to the usual good advice above I'll throw something else into the pot.

If you willing to sacrifice a few cc's for a smoother higher revving engine then this combo I just discovered is interesting.

Firstly if you have a 4.0 block then the crank has the crossbolted 4 bolt mains which are vitually unburstable so a girdle plate isn't really necessary.

I would have the block pressure tested as the 4.0's seem to have more issues with cracking than the earlier blocks, top hat linering if within your budget would be a good idea.

The combination I have worked out is a 4.6 82mm/3.228". crank Rover 4.0 rods and a Manley forged oversize 3.7" 4.6 Modular Ford piston.

The Manley piston has a Compression height of 1.220" the Rods are 6.110 and the crank throw is 1.614" = 8.944" the Rover deck height is 8.96" which puts the piston 16 thou. down the bore at TDC The Ford pin is .866" and the Rover rod is .966" so will require a 100 thou bush which is simple to do, and with a rebalance you just bolt it together.

With all the money you would save you can spend elswhere on valve gear etc.

Kevin



Edited 1 time(s). Last edit at 10/28/2009 06:13AM by castlesid.

Hi Castleid,

Thanks for the input. Nice very nice indeed!

But if I may, and understand that its just my lack of knowledge here, but would not adding a 100 thou bush be the weak link in that setup. Will the bush not have a tendancing of wearing unevenly ?

Could we not get a rod at 6.120 with a .866 and have 3thou planned on the deck giving us a 2 thou clearance.

I thought that the piston should be at bore at TDC.

But I do like to save :)

Nice stuff, now you guys got me thinking, which is something I do not do often ;)

./RB

Rino,

Bushing the rod should have no effect as far as strength or wearing, 16 thou. deck clearance is much better than the standard rover engines which are normally 30 - 40 thou.

As for the strength of the standard Rover rods, a friend has just done a season of drag racing using a standard Rover 4.6 crank and rods and uses a 250 shot of gas to achieve over 600 ft/lb of torque and has had no problems, he does have forged pistons.

The pistons are priced at around $300 and come with flat tops for a very high comp and other styles but you would need to check depending on what compression ratio and camshaft you intend to run, a wide overlap (hot) cam will reduce the effective (dynamic) compression ratio. Bore size of piston is 3.7" same as Rover standard size so if bores are good no need to rebore just have the block cross hatch honed. They may do oversizes if you need/want a slightly bigger bore.

Is this an engine you want to run on the street?

The main issue with the larger capacity Rover engines is their ability to breath, if a set of TA heads is within your budget this would make a very nice engine.

You mentioned the Hardcasle book which is ok for basic if a little dated information, for more detailed and up to date data I would recommend the Des Hamill book "How to Power Tune Rover V8 Engines"

Kevin.

How do you specify the 94mm bore version? The stoke bore of the 4.6 is 90mm. I've found a bunch of references on the net to 94mm blocks... This piston would work for the 350 crank in a rover block too! I just gotta work some numbers.

Great find Kevin.

Nick,

You beat me to it. I was just checking the Manleysite and you are quite correct re the ford 4.6 bore size at 90mm and 4mm is a hell of an increase in bore size.

I looked at the e-bay site again and they state 3.7" Big Bore so I don't think it's an error, hope not because one of our guys has just ordered a set for a 4.6 rover.

Link to e-bay seller.

[cgi.ebay.com]

Kevin.

Further checking of the Manley catalogue reveals that they do in fact do custom forgings up to 3.7" for the Ford 4.6 modular forged piston.

Link.

[www.manleyperformance.com]

Scroll down to page 106.

Kevin.

LOL! I just found that too. Well about a half hour ago when I started writing the new thread about these parts. You really got me goin', Kevin!! Holy @#$%&. What a find. Thanks man.

Nick,

Yes a good find, perhaps more important on our side of the pond because a set of forged pistons for the the big bore Rovers are around £800.00.

If only our engine parts were at the same price you guys can buy them for, anything in the UK is x 2 at least.

Kevin.

Dag-gonnit Kevin...and I was just going to stick a decent cam in my 4.6.

Tony,

I think you have plenty of cam choice over on your side and more access to custom grinds if required.

I used a Crower 50232 in my 4.35 and really like it, I have Buick 300 heads with big valves and the usual mods to seats and bowl areas.

It will pull down to 1500 RPM in 4th gear peak at 5500 and is said to be strong to 6500 if required. I've only had the engine to 5000RPM as running in and it gets there very quickly at nowhere near WOT

Kevin.

Kevin,

The more I read and search, the more I like your setup!

Though I cannot find alot of info on the TA heads yet, or maybe I am not looking at the right place..

So far my build as been steering some interest of our offroading group and a few want to a rebuild for their portal equipped trucks.

Your setup looks quite right for this, since I need torque at the mid range..

I am still debating EFI for the portal project, since the only other viable option for induction is a Holley TA and I am not too happy with that, also I can recoup the coil pack and go full Megasquirt with the EDIS spark code, but this option is not field servicable..

If I can get snorkels for weber side draft ;)))

TA is about halfway through the process of writing the program and setting up to machine the new head castings for the first production run. There might be one set of those heads still available and they will probably ship around the end of Nov or shortly afterwards. Price will be in the $2000-$2500 range.

Jim