The Wedge Shops Single Turbo TR7V8 build

[thewedgeshop]

As some of you may know, or not know, I am have been in the process of building a Single Turbo Rover V8 setup for my 1977 TR7 FHC.

The motor will be a stock rebuilt 3.5 Rover with std compression (8:1) which is ideal for the turbo application. I will be using Cometic head gaskets,in which the heads have been shaved down to accommodate the extra thickness of these gaskets. Erson cams has designed a special grind pattern for the application that will be suited for the turbo application with power from 2500-6500. A Holley 750 blow thru carb will be made specifically for my setup. The Holley will sit on top of a Harcourt single plane intake manifold. The setup will be intercooled with 2.5in piping.

The transmission will be a stock rebuilt Rover trans LT77. The car already has The Wedge Shop Mustang rear end conversion and all the other goodies.

I will update the thread over time with my progress. I plan on making the turbo setup into a kit in which anyone can bolt on their stock 3.5 with no modification and push 250Hp to the wheels.

Here are some more specs on the setup.

Specs on Driving
Street car
1 -5 drag passes a year
Driven to cars shows 600+ miles
6300k Redline
Drive ability is important
300-350WHP Target

Quick specs on Motor:
215 cubic inch
Aluminum Block
Aluminum Heads
Fresh rebuild
ARP hardware
Cometic Headgaskets
Makes 210hp in NA form

Specs
Rover 3.5 (215 cu in)
8:1 compression
93 Pump Gas
ARP head studs, main studs
Stock Heads
Erson TQ20 on a 112 (478 lift, 214 duration at .050)
Cast pistons, rods
Single plane intake (Harcourt)
Blow thru Carb (Holley 750)
10-15psi max
Mallory 6 Box (Boost timing retard functionality run off MAP sensor 1* timing pulled per 1LB of boost)
Intercooler Core Size 11"X12"X3" Overall Size 18"x12"x3" 2.5" Inlet & Outlet 3" Core
3 in Mandrel bent exhaust from Downpipe back w/ Vibrant 3in Streetpower muffler
160* thermostat
Mallory SS distributor 24* advance with 10* static advance
1 PTE 46mm External Wastegate
1 Tial 50mm BOV
Garret to4e 60 trim .58 A/R O Trim T4 exhaust housing with 3in Vband outlet



































Thanks
Clint
The Wedge Shop


www.thewedgeshop.com

[roverman]

Clint, I'm curious as to why you chose a 3.5L over a 4.0L ? As I understand it, the "fifth" head bolt can be added to 4.0/4.6 ? Nice use of skill sets. Cheers, roverman.

[thewedgeshop]

Roverman,

I chose the 3.5 as I wanted a nice baseline for what can be done with these motors. Also the fact of cost played a part. I think the 3.5 is a great motor with the limiting factor being the heads. In the future i plan on building a 4.6, which will be an easy swap as all the turbo stuff will not have to change.

As soon as I get some results I will let you guys know. Should be up and running in a few weeks.

Thanks
Clint

[thewedgeshop]

Some quick vids of it running.

Car still has some bugs to work out, currently is running great on 10psi at half throttle, but is having some issues at full throttle. Will try to sort it out in the next two weeks.


http://youtu.be/ecIH4YAtBxg


http://youtu.be/cMqX5duPgOM

Thanks
Clint

[Jim Stabe]

I ran a turbo 215 Olds in my MGB roadster for about 10 years. I didn't have the advantage of an efficient turbo like you do ( I was using the Olds Jetfire turbo with a 2" SU) but I did run as much as 15 psi boost. The car was really quick with 15 psi but I was warned that the compressor wheel would be life limited at that boost level so I lowered it to 11-12 psi. I was running 8.8:1 compression with Olds heads (for the extra bolt) and I would recommend you look into water/methanol injection to supress detonation if you get up into the 15 psi range, with the cast pistons you REALLY don't want the engine to detonate.

[roverman]

Clint and clan, You might want to consider a "thermal barrier coating", on those cast slugs. I had a customer was running 20-22 lbs. on a 4.0L(coated oem pistons). His waste gate was jammed shut, unknowingly. He eventually heat eroded a piston down to first ring.  Good Luck, roverman.

[roverman]

Jim, As I recall, you were also using a Jet Fire short block ? This would also help longevity, with thicker piston crowns , main caps, and longer main bolts.  Meet Coronado Speed Festival ?  Cheers, roverman.

[Jim Stabe]

"Jim, As I recall, you were also using a Jet Fire short block ? This would also help longevity, with thicker piston crowns , main caps, and longer main bolts. Meet Coronado Speed Festival ? Cheers, roverman."

Nope, just the Jet Fire blower. I built an Olds 2 barrel engine and altered the wastegate on the blower with a heavier spring and an adjuster mechanism to get the extra boost. I originally tried to use a Weber DCOE carb but it wouldn't meter properly over that wide aa range of airflow. I eventually fixed the problem with a 2" SU from an XKE.  I sold the Buick engine to Lloyd Faust and we put it into his MGB roadster also with a Jag rear suspension. Haven't decided yet on attending the Coronado event - convince me!

Clint's setup ought to scream with a good turbo and 15 psi.

[BlownMGB-V8]

I also ran a Jetfire turbo with a 2" SU. Never got the boost up that high on that motor though. It was a stop-gap powerplant and eventually the turbo shaft bearing got loose enough that the fins started hitting the housing in a hard turn. But it did teach me a thing or two about turbo lag.

Jim

[Jim Stabe]

I did all this when I was younger and didn't know any better. I had a chance to talk with the engineer who developed the turbo for Oldsmobile back in the day and he told me that the only thing that saved the turbo from grenading was that I had a non restrictive exhaust and I didn't hold it at that boost for very long because it was turning around 150,000 rpm at 15 lbs boost. He said that they destroyed several units in testing at that level of boost. He strongly recommended I dial it back to under 12 psi. It killed my soul to do it because it ran SO strong at 15 lbs. I know what you mean about the lag, it teaches you the skill of anticipatory throttle application.

[roverman]

Perhaps you guys didn't experience it's cousin competitor, the Corvair Spyder, now "that" was turbo lag. Rajay turbo had an oversize turbine and housing so it was impossible to overboost, on a stock engine. This negated the need for a wastegate,(cost saving). There was no water alcohol injection, like Jet Fire used. Cheers, roverman.

[BlownMGB-V8]

I had one of those too. It lagged so bad I seriously questioned if it ever really got any boost at all. So between the two I was pretty much done with turbos. When I went to the Eaton M90 I found that to be everything I was looking for, but at 16psi+, (pegged the guage) like you Jim, I found myself SOoo reluctant to dial it back, despite erosion above the top ring land. When the blowby and loosening of the head bolts got excessive to where a backfire blew out the lifter valley pan I had to choose between that and a newer larger engine, so out it came. And now it's been what,  three years maybe? Feels like it anyway.

So my advice is to go big on the displacement and go rigid on the engine, particularly the block. Overkill there will pay off in longevity. That is why I switched to the iron 340 SBB block. Though in retrospect a 300 block, even stroked to 350 would have been a much easier choice, and if one is not tied to the SBB/Rover port layout the way I was with those big swoopy custom equal length fenderwell headers, a new 5L Ford roller motor is hard to beat. I think they have even more displacement potential. The block is not nearly as strong, but who needs 500 horsepower in a sub 2500 pound car anyway, right? Oh yeah, I'm forgetting Art.

Jim

[roverman]

For those of us still feeling guilty about 1776....we must pay homage to the RV8, for better or worse. Many will jump ship, and take the EASY path to hp., too bad as the Rover will have a glorious finish, IMHO.  roverman.

[Jim Stabe]

Jim

Speaking of 500 hp in a sub 2500 lb car - when are you going to have that beast running? And no, you can't ask me the same question.

[BlownMGB-V8]

Well, kinda OT, but I hope to finish the mechanicals by year's end, and then start on the electronics so spring is a very real possibility. But no turbo this time around. And Art, it may not be a Rover but it is certainly in the family since really,  the Rover is a BUICK!! So really,  my 340 is closer to it's roots than your Rover is  

So Jim since you brought it up, when Will you be getting that monster on the road?

Jim

[Jim Stabe]

I told you you couldn't ask but since you did, I will probably have it running by next spring also. I will finish the windshield this weekend if I don't break the glass at the last minute and that will be my biggest hurdle out of the way. The next big challenge is the hood but it should be anything like the windshield was. After that it is just finishing everything and wiring it up and plumbing it. After I'm sure everything works and I'm not going to modifying panels anymore, I'll take it apart and make it pretty.

Sorry for the hijack Art.

[BlownMGB-V8]

Ah yes, the prettiness part. I'll be lagging behind on that part I expect. It will leave me something to look forward to for the next winter and in between I can convert the carport to a paint booth. Then there will be Matthew's car, and Dave wants to build one, and I even told Carl he can paint his here so I don't forsee things slowing down much around here, especially with the big honeydew projects I get entangled in. And of course there is the tractor restoraton which is moving along well. At this rate it is a wonder I get anything else done atall.

Jim

[roverman]

IMHO, the FIRST production aluminum V8 is still worthy. It wasn't considered so by GM, but at least the British did. Because of this, thousands of lighter and good handling cars, have been built. Where would lbc's be now without the RV8 ? Somewhat like pondering the developement of TF  drag racing, withourt the early hemi ? I can only wonder if David Vizard had spent his labor developing a genuine race head for the rover/sbb, instead of modding one pair. The TA head is a step up from the Merlin, but is that enough ?  roverman.

[MGBV8]

Let's see.....Rover is a Buick.  Buick is GM.  Chevy is GM.  Rover engine & LS1 are cousins. Family is family!  

[BlownMGB-V8]

Chevy and Buick V6's too. But whatever are we to do with all those Fords?

Jim

[thewedgeshop]

Finally got the car running correctly. Had to change out the carb hat and for the time being cut a hole in the hood.... Not my first choice, but had to get it to The Roadster Factory show and not having a hood that closes was not an option.

Here is a quick 3rd 4th gear pull. Car runs strong and am expecting 275-325whp when I get it back to the dyno.

http://www.youtube.com/watch?v=GSAYZ_Lsr2s&list=UUBMoxoXo7Jyrw2WPy9DN23Q&index=3&feature=plcp





Thanks
Clint

//www.thewedgeshop.com

[thewedgeshop]

Car made 278whp & 305wtq @ 10psi. Still has more in it with some added boost and timing.

Video below.

http://www.youtube.com/watch?v=_HJI_wSxQIE&feature=youtu.be