Engine and Transmission Tech

Nicolas. Yes, you're right about that, every little bit of weight saving helps. And, for better weight distribution it's the same.

The only thing seems to be how much time, work, money is it going to take and does the end justify the means?

Trip

Hey Trip,

Re the CAD drawing ... not a wiz, just persistent. I will be fabbing up (converting) my TR7 subframe for the RV8. I already have an engine, bell housing, & mounts (engine and tranny). I've also put on a Buick V6 timing cover and made my own shortened water pump pulley (actually an adaptor).

In the drawing, the upper right section (a-a) shows the engine already lowered about 21mm (from 38 to 17mm). According to my measurements, everything will clear the subframe for my RV8-3.9L. As well, I plan to set the engine mounts about 1 to 2in back, as soon as I can determine the clearances.

I have to make up the subframe mounts and a driveshaft anyhow, so I don't foresee any major challenges.

Martin

Hi Martin,

You've already got an engine etc... you're way ahead of me.

Have you taken into consideration the steering and header clearance?

Also, the exhaust and drive shaft will have to be shortened and the tranny mount adjusted.

What about the sump?

I hope you adds posts and pics of your build. I can't wait to see your progress!!! It will be cool!!!

Trip

For exhaust, I have a used set of Ted's (TSI) headers that I will modify as needed.

For the driveshaft, I have a slip joint shaft from an early Range Rover that should work just fine, as long as I redrill the ends of the u-joint flanges to suit the TR7 bits. If I have to shorten it, I have a friend that has lots of experience doing it.

I also have a sump and harmonic balancer off of a SD1 wreck I found.

My RV8-3.9L engine is completely rebuilt, +030 - 9.35:1 pistons, Rover 4L heads (which will up the compression to 10 point something...), a medium hot Erson cam from Woody's, high capacity oil pump, Edelbrock 4bbl carb and intake. I'm almost finished a mild porting job (soul sapping work, best left for a cold winter night), and then I can button her up.

With the summer, I've been distracted with other toys, dog and wife (not necessarily in that order). With fall around the corner and cooler weather, I can re-start finishing the porting job. Once that's done and the engine is closed, I'll drop the TR7 engine, tranny and sub-frame from the car and being the conversion. The interior is already done and the body is relatively sound.

After that, I'm also planning on upgrading the front brakes with Toyota Cressida 10.7" disks and 4Runner calipers, but that's another AutoCAD drawing and story.....

Another year or so and she'll be ready for paint...... :)

M.

Martin, one of the other things I was concerned about is the fact that when the engine is dropped lets say 1", then the angle of the driveline to diff. changes accordingly and has to be changed to re-line everyhing.

BTW... reeeeally nice work on the porting. Looks like apro CNC job!!

Hope you were able to find all the metal bits... Talk about soul sapping work. LOL.

You said - Toyota Cressida 10.7" disks and 4Runner calipers. Really? I hadn't realized that you could adapt those easily. nice.
Prolly pretty easy to get and at fair prices too.

Keep us updated

Trip

I am bringing the engine back 1-inch and until I get a dry sump arrangement plan on keeping it at the stock height. The bell housing bolts for the transmission will get real tight to fit but should be ok. The headers might come closer to the steering shaft but this will be verified when I mock everything up.

Mike, that's exactly what I would like to do as well!

Please keep me updated as you go through the process. I'd love to here more about your project.

Trip

BTW. Did you custom make those mounts?

Trip-The brackets were from and made by TSI and are OK for fit but needed some holes opened up and will need some spacer for each of the upper bolts. I welded on some extensions for the rubber engine mount and also extended the gusset too. It was not that hard at all. The original Rally TR7V8s moved the engine back 2-inches and really hammered the transmission tunnel to death but they aslo made it so just the gearbox without the bell housing could be changed out so they did not need access to the bellhousing to engine bolts. As a result of oving the engine back you will need to shorten the drive shaft, move the bolt holes in the floor for the transmission cross member, either get a shortened shifter assembly or notch the hole in the tunnel, and the headers can add to the mix too! I like the idea of a chevy LS1 type engine in a TR7. Are you still thinking chevy or rover?



Edited 1 time(s). Last edit at 08/28/2009 12:25PM by WedgeWorks1.

Hey Trip,

Where are you located?

Dan B

Hello Mike,

It seems that most tr7/8 owners are not attempting this relocation and I got the impression the minor gains weren't worth the effort.

The fact that you're doing it and that you say it's not that hard is making me reconsider. Here's the thing, yes, I am still thinking about a Ford 4.6 or LS1. I'm now also considering a Ford 302. Good strong, reliable and tonnes of performance parts. Easy to make crazy HP! The Rover motor is an awesome, light and very capable motor... I have concerns about the porosity issues in some of the motors. Tho I know that they can refit those blocks with "top hat" liners which are flanged at the top and seals to also help prevent the other Rover issue - dropped liners. I am amazed at the availability and variety of quality performance parts.. You can even use some of the Buick/GM/Chev components.

One bit of advice I would give if you go the Rover direction... From what I've seen the "Coscast"(originally designed by a CO called Cosworth and now by Mahle) blocks that are being used to eliminate the porosity issue, are actually now coming back with the same problem. So I can't justify the high cost of these blocks. If you decide Rover, look for a newer engine rather than an old unit, and have it inspected before you drop it in the car IMHO.

The issue with the Ford and LS1 is the weight(especially the LS1), height and length... Relocating the block back and lower, in this case becomes even more appealing with these heavier motors. Don't like the idea of the engine ahead of the front wheels and sitting on the front bumper!!!

How to access the clutch easily, when needed if the bell housing is near the firewall?

Sounds like a shortened shifter housing would need considerable fabricating. I wonder if any company supplies them for various Trans?

Trip



Edited 1 time(s). Last edit at 08/28/2009 01:44PM by TRip.

Hey Dan B... I'm just a little bit north of South Charleston, WV.... Just a short little drive.

Canada.

Trip



Edited 1 time(s). Last edit at 08/28/2009 01:45PM by TRip.

Trip-Believe it or not but I own (2) 1980 TR8 coupes that are genuine “retail” cars. They both have started off somewhat stock. They are also about 38 cars apart from each other in the production run. I have owned my white coupe since 1998 and it is being turned into a road going rally car. The other is a pageant blue coupe that I picked up about 3 months ago and is my 30th wedge and 5th TR8 all starting in 1986! The car is a rare color that is going to be kept stock as much as my patience will allow. The rally car has the original motor that needed a rebuild but is being replaced with a TR8 Rover V8 built to the max for a 3.5 liter; .060 over bore, 12.5 compression, 520 lift cam, over sized valves and ported heads, roller rockers, tubular push rods, offset grind crank, chevy 327 H-Beam connecting rods, double roller timing chain, and fully blue printed and balanced. The engine has about 2,000 miles on it and last dyno was 320 hp with 340ftlbs of torque. I seem to be the only one moving the rover rearward in a TR8. Group 44 TR8s, Rally TR8s and other factory racers moved the engines 2-inchs back and made a huge handling difference. I think for a TR8 with all the parts that work why bother is the attitude by owners.





The rover block you are talking about with the porous issues are the 4.2 and 4.0 liters that had the liners separate from the casting dumping coolant out the exhaust ports when they would heat up to operating temperature. I had seen this happen about 5 or 6 times. I stay away from those blocks. The later blocks after the late 90ies were fine unless you do some radical honing or boring of the blocks that might in a rare opportunity break the liner/casting bond. The top hat lines are a neat setup and with some head gasket with o-ring combinations should hold back any issues with coolant. I still think a hot engine would be a built 4.0 or 4.4 liter with bore/stroke combinations.

I have a friend with a “disgusting” Group 44 replica TR8 running a small block dart chevy 427 block de-stroked to a 383 and shoveling power in by a huge turbo. He has the power going through a T56 ending at a Ford 9-inch Detroit locker. Here is the deal moving the engine back no matter what it is; Rover, Ford or Chevy can be done and with a welder look like it was a factory install. Considerations are modifying the transmission tunnel, headers/steering shaft, shifter, drive shaft and keeping the fresh air duct for the heater core in place so you don’t drown your engine with water rusting things up after all the work you put into it!

Mike,

You're engine list reads like poetry!!

Did you say 30 wedges?!!! and 5 V8s?!!! Now that's impressive.

I'm just on my first.

Thanks for the Rover 4 and 4.2 info. I'll definitely avoid those.

"a huge handling difference", I like the sound of that. Now, I'm reeeeally enthusiastic about relocating the motor back and lower which should be possible with a dry sump... I think.

A 427 actually fits? Wow!

BTW, Re: Group 44 replica TR8. Do you know if there are any body kits besides the Lanocha and Huffaker kits?

Thanks for the insight, Mike

Trip

Trip-You will be surprised at how much room there is in the TR7. Tim Lanocha has a small block 427, not the big block version. I have seen 454s stuffed between the shock towers! The body kits from Lanocha Racing are the original Group 44 molds for all the fenders, hood, trunk & doors with some molds made from the front & rear spoilers. The irony is that not even Group 44 or the owners of the 2 TR8s have these molds but have made some of various panels. The Huffaker panels are nice but don’t give a true racing look. There are various kits available from the UK that look nice and with some decent amount of body work will get you some more room for wider tires. I have all original rally fender flares and front spoilers on my Rally car. I go REALLY wide in the back and up to a 10” rim and up to an 8” rim in the front and it don’t hurt the look of the car at all. There are three sizes and lengths of fender flares for the rally car. I heard you asking about various topics/items with your project; engines, transmissions, rear end, and now seat bolts. You do have you hands full. Imaging trying to resurrect a TR8 and build a full competition Tr8 with only two hands and limited time! Somehow in about 100 years the rally car might touch the ground and soon the stock TR8 will be cruising!
The rule of thumb with the Rover V8s is if it has the 4 bolt mains and was running you have a good base to start with. If you buy an unknown motor especially one that was from a dealer who pulled and replaced it you have one of two issues; liners or oil pump. It is a 50-50 chance of wasting money. The older 3.9 and 3.5 liters are just as good. Never thrown a rod or crank in one or anyone I know of yet with the 2 bolt mains.

Mike,

For the sake of the record, and it may have been a typo, but it is mainly the the later 4.0 and 4.6 four bolt main engines that suffered from block cracking and liner slip.


The 4.0 are the worst blocks as the engines were built from blocks with more core shift, the 4.6 were slightly better grade blocks.

The 3.5 rarely has a problem because there is a lot more material behind the liners The 3.9/4.2 which is the same block also rarely have the problem.

The problem with the later engine is attributed to the fact that the late blocks suffered from core shift in the casting process, and that they were run at higher temperatures for emission reason.

Of course any of the Rover engines that has been seriously overheated or suffered coolant loss, can suffer from this problem.

Picture of the block problem of a late block showing how little material there is behind the liner.



Kevin Jackson.

Kevin-Thanks for the correction or clarification! I meant the 4.0 andd 4.6.......too many litres out here! The 3.9 and 4.2 blocks are on the same level as the 3.5s......I had a 4.6 that needed an over bore for a friend of mine and when the machine shop bored the cylinder the bond for the block and liner broke free. Only until it warmed up did it yield the ugly secret! He had to use a new 4.0 liter short block assembly just for the block and it came out fine.

Mike, 454?!! Do the rear wheels actually touch the ground?? LOL

They must have done some serious relocating back and lower to keep a reasonable weight distribution and handling.

I would looooove to know how they did it!

10" and 8" rims, are they custom 17 or larger diameter?

Yes, I do have my hands full but still can't imagine the amount of work and research you must be enduring in order to build a race legal rally car. It makes it a lot more difficult when there are such ridgid racing requirements and rules compared to a street project.

Okay, I'll keep your rule of thumb in mind.

Thanks,

Trip

Kevin, thank you for posting the cut-away pic of the block. It really does help to have a visual showing the cause of porsity in the 4 and 4.6 blocks.

Trip

I would think that the 455 Buick would be a better choice than a 454, since it is significantly lighter.

Jim

Oh, I like it... a Buick 455, interesting suggestion.

Trip