So to open up an old thread..... I am picking up some GT6's this week. One is for a customer, one will be for sale and one is for me :-)
My customer is looking to do an engine swap and we are considering the options. So fast forward to 2021, what is the thought for a modern, high performance engine for the GT6 platform? As much as I want to keep a straight 6 in it, the Triumph engine just barely fits and is pretty heavy on the front of the car and messes with the handling verse the lighter Spitfire version. So my heart says BMW S52, by my brain says use a modern turbo 4 cylinder. Thinking the smart choice would be to do what TVR Scott is doing and go with a Ecoboost 2.0 and a Miata NC 5 or 6 speed. I know we can't get the controllers/harness from Ford Performance, but the alternatives from SCS-Delta in the UK look like a good solution.
The rear end situation will be resolved with an R160 and CV axles for the Rotoflex, so my engine choices are pretty much more about packaging. So what are your thoughts?
In reply to dherr (Forum Supporter) :
The 4.0 Jaguar is an all aluminum straight 6 with a fantastic history of reliability. Very powerful with an optional supercharger. The NA one is 290 hp and the supercharged one is 370 hp.
The Atlas engine which was derived from the Jaguar is bigger and several inches taller. So it probably won't fit.
I have seen both SU carbs and Weber's on the Jaguars but I doubt they make the same power.
frenchyd said:
In reply to dherr (Forum Supporter) :
The Atlas engine which was derived from the Jaguar is bigger and several inches taller.
Yet to see any evidence that the GM Atlas engines were derived from the Jaguar i6.
I wonder how the Volvo SI6 (Short I6) might work.
Pros - Aluminum block and head. Engineered to be short. 230+ HP.
Cons - I think only comes in transverse layout so who knows what trans, etc.
Ported 13b! brap brap brap
Something without a turbo might be easier to package. Like a Honda K-series with one of the various RWD adapters.
231 Buick V6. Was working on a Spitfire swap when the car was stolen.
Gm60*v6
In my miata its a RIOT. And they do a 3.4 kit for the mgs, so....
A 3500 or 3900 vvt engine would be even more fun.
How about the engine from a Mazdaspeed3? 265HP
In reply to triumph7 :
Isn't that a DI engine? Might be a new an interesting level of pain to swap that in.
A sadistic part of me wants to copy this some day...
Any drivetrain swap into a Spitfire or GT6 will be a PITA, so I have a hard time arguing against an LS. Maybe a Rover V8 if only to keep it more British...
LHU Ecotec (270hp/260lbft) as found in the 'Pink Panther' executed by Loosecannon.....
In reply to kb58 :
GRM did a Rotary in a Spit several years back. Joe Curry also did one a while back I don't know if he's on here or not. He also used to market camber compensators for the swing axles.
wspohn
SuperDork
2/9/21 10:44 a.m.
If the I6 Volvo is too long, there is always the I5 version....
Ecotec or Ecoboost are looking like my first choices (easy support for RWD and 5/6 speed manuals) and ability to tune with compact size. Got the cars last evening, going through them now......
In reply to dherr (Forum Supporter) :
The odd thing about either of those options is they are surprisingly wide once you hang the intake and exhaust off them. Sometimes even wider than OHV V8's - or close enough to make arguing against the V8 harder. And they are often taller than a V8.
I'm lazy, so I my plan is to just spend the $$$ to make the 2.0 the best street engine it can be.
The Daewoo straight six XK series motor. Relatively short because it was designed for transverse installation , all aluminum block and head, torquey rather than powerful, rare as hens' teeth in the US unfortunately. Less rare in Canada.
In reply to DeadSkunk (Warren) :
I was jut thinking this. I kinda want to swap one into a miata just because.
bobzilla said:
In reply to DeadSkunk (Warren) :
I was jut thinking this. I kinda want to swap one into a miata just because.
I would tread carefully with that engine. I have it on good authority they warp cylinder heads consistently and way too frequently...
Tom1200
SuperDork
2/10/21 10:16 a.m.
So the problem with modern twin cam 4 cyl turbos is they often weigh as much as push rod V8s, as well as the aforementioned packaging. Of course a GT6 engine is probably around 400-450lbs so it's a wash.
So under the kooky conversion I like the idea of a 3 cylinder Ecoboost, here's why;
150-200lbs lighter than the GT6 drive train.
25-80hp more than the standard GT6 engine depending on which displacement engine used.
Unique exhaust note of 3 cylinder engine.
The idea of a 1700lb car with 150hp sounds like a fun street car to me.
wspohn
SuperDork
2/10/21 11:35 a.m.
Tom1200 said:
So the problem with modern twin cam 4 cyl turbos they is often weigh as much as push rod V8s as well as the aforementioned packaging. Of course a GT6 engine is probably around 400-450lbs so it's a wash.
LNF engine = 360 lbs.incl. turbo
GT6 = 401
LS series = 478
Some of you will not be surprised at my suggestion, but a 2.5 mzr/duratec with appropriate turbo will make a comfortable 300+hp. same transmission options as the ecoboost. No DI means easier control.