Triumph Sports Cars

Hi guys - my newly professionally rebuilt TR4a is pumping coolant out the rocker oil weep holes and I am kind of fed up with it. Since I am looking at a full rebuild to fix it I am wondering aboutn Nissan or Toyota inline 4 swap. Those engine are about 24 inches tall and 24 long, width varies by accessories and intake. Thinking about has be wondering if a GM V6 would be just as easy of a fit.

Anyone have experience with a Nissan or Toyota inline 4 swap? Dimensions of V6 handy?

Thanks!

I supposed I should be considering the Ecotech 2.2-2.4 as well.

Tom welcome to the forum.
I put a 2003 GM 3400 in my TR6 and it involved no major cutting or hacking to get it to fit.
It bolts up to the existing TR6 engine mounts on the frame with mounts I designed.
The engine bay and frame of a TR6 is very similar to the TR4a so you could go this route if you wanted to.
If I was to do it again I would go with the GM 3500 as it has about 25 more horsepower but has the same dimensions as the 3400.
The 3400/3500 will use the following setup for transmission and bell housing if you go with a Ford T5 transmission :
1998 Chev Caviler flywheel
1992 1993 Chev S10 ( 4 cylinder model) clutch diaphragm
Mid 90's Mustang SVO clutch plate
Mid 90's Mustang throw out bearing
1992 1993 Chev S10 (4 cylinder model) clutch fork
1992 1993 Chev S10 (4 cylinder model) bell housing. Note the transmission hole needs to be opened up a bit for the Ford T5 transmission
1979 1993 Ford T5 transmission (V8 model) note this has a better first gear ratio.
For a clutch slave you can use a modified Pontiac Fiero slave. You can buy this set up from British Car Conversions.
I used an early MGB clutch master cylinder as the TR6 master cylinder is slightly smaller and does not move enough fluid.
Your other option is to use a bell housing and clutch assembly from the early 2.8/3.4 Camaro V6 cars.
I would not use the transmission from these cars as the first gear ratio is too low for a light car like the Tr6 TR4a. I would use a Gm world class T5 out of a V8 car as it has a better first gear ratio

The Ecotec is a good choice also. If you can find a wrecked Pontiac Solstice then salvage the whole drive train and put in your car. This is the way to go as you have the whole thing!!
If you can't locate a Solstice then go with the Ecotec engine and buy a bell housing from Quads for Rods and go with the clutch assembly they recommend. You will have to go with the GM world Class T5 out of a V8 car.
The Gm 3400/3500 and the Ecotec will involve some work in terms of the engine wiring harness and re programming the ECU.
If you go with the V6 route I will give you more info on the the swap as there is lots of stuff to consider.

Cheers
Byron

Thank you for the detailed post Byron, very helpful!

You have two other choices that would work quite well with your car:

A drive train out of a wrecked Honda S2000
A drive train out of a wrecked Mazda Miata
The Mazda engine is a bit short on power compared to the other options but it is a good drive train. Guys are putting turbos on these engines and getting around 200 250 hp from them which is ample for a Tr4a.
More ideas to consider.

cheers
Byron

If you are looking for a Solstice engine/transmission, here might be a good source.[www.v8pontiacsolstice.com]

I would like to have the TR4 engine, so I suppose you are a LONG way from Nevada?

What about the good old Iron Duke 2.5 GM 4 cyl?
They came in rear wheel drive versions, 5 speed or automatic, fuel injected or carb'd. Later models came with cross flow heads.
Available all over the place for cheap. Performance support is very good. Pontiac's Super Duty program had them making 330 hp.
Later versions had a balance shaft that made them very smooth.
They are roughly the same size as the old farm engine that the TR came with. Lighter than the stocker and a much better transmission. And they look similar to the original. Section the valve covers together and most people would never notice the difference. The non cross flow engines even have the manifolds on the right side to make your swap easier.
Whats not to like?

Cheers
Fred

A minor nit-pic, slightly off subject.
TR sold engines to Ferguson for tractors, they are not tractor first engines adapted to Triumphs.
Really weary of that old myth.

Didn't mean to slam the engine design Richard. I am aware of its origins, and it's a testament to its rugged design that it was utilized in an agricultural application. It is a torquey little four and the old buzzard moves the early TR's along surprisingly well. I have built quite a number of them, a couple with turbo's and a few with fuel injection. It's just that it's a small bore, 3 main 2.1L motor that doesn't like to rev and it is a little on the portly side. As an aside Toms motor probably doesn't need a rebuild it just needs the liners to be sealed and shimmed properly.

Live like you mean it.
Fred

Hi Tom,

I'm a bit late to the party.

Something that might be of interest is that the GM 60 degree V6 was designed to fit in GM cars that the small 4 cylinder engine bay platforms had already been designed to. New more powerful choices were required so the compact 60 degree was produced.

In terms of numbers,

the stock 3.4L V6 produces 160 BHP and 200 in torque.
the stock 3400 V6 produces 185 BHP and 205 in torque.
the stock 1st 3500 produces 210 BHP and 220 in torque.


These engines are all about torque. The torque numbers between the 3.4 and the 3400 is not enough to consider. The numbers to the 3500 (early version that does Not have VVT or cam phasing) is a decent jump but costs jump to use this engine. All of the engines have good potential so none of these three should be dismissed. I am not a huge fan of the earlier 2.8 and 3.1 only because the 3.4L is actually not that difficult to come by and the pulley arrangement is the easiest to use of all engines along with other items. The 3.4L can be used more completely from one engine and potentially one car (Camaro/Firebird) than any other engine conversion. There are a few who dismiss the 3.4 for the 3400 because of the difference, it might be of interest to hear that 3.4L conversions are far more common compared to 3400/3500 conversions at about 20 to 1.

All these engines, just like any other Air Pump are able to produce higher and better power. We had a 3.4L recently produce 215 BHP and 254 foot pounds of torque. That is an engine that still idles and has power from idle onwards, not a race motor. We were not aiming for a race engine with no tractability.

This said, there are also decent V8 and other V6 engines but finding something that has been used for a conversion previously means that the total time and understanding to fit will make things move along significantly quicker. Since the MGB has a tighter engine bay but has quite a few engine conversions, look into the various engine conversions used in the MGB and much of this can be fit to the TRx cars pretty easily. Now if you had the Spridget or spitfire engine bay, I have to be a bit more careful to say that as it does not always hold true... Although I did once install a 3.4L SFI engine into a Spitfire engine bay as well.

-BMC.

If you are looking for a Pontiac Solstice for a power train, don't forget the Saturn Sky-same car different badge.