The V8 Owners Forum -

Bit new to all this so need a bit of help here . Want to replace the 4.0 engine with a 4.6 into a pre cat 1992 Griffith . Can i convert serpentine engine to single belt using 4.0 parts . Can i fit my 4.0 big valve hads onto 4.6 range rover engine and would that bring up the low compresion to a higher level . And will all other ancillaries fit the later engine and how would the 4.0 injection cope .

Thanks Roy

Hi
I'll answer what I can others will add more later
The front end set up on your 4.0 will transfer across to your 4.6, there may be differences in the cam blank but buy the cam for the model year of the 4.0 and that will work.
The heads will go straight on.
If you want a higher CR than fit the 4.0 pistons onto the 4.6 rods when you fit the 4.6 bottom end, deck the block to the pistons (the decks are rearly flat or square to to the crank centre line and it is a good opertunity to get the pistons at the right level. If it has tin gaskets and you want to fit composites then skim 25 thou off the heads to compensate, however I would measure everything first !
The injection will cope as badly with the 4.6 as it does with the 4.0, I would contact Phil Ringwood (extra efi) on here and replace the rover ECU with one of his kits.
I hope that is some help.
Best regards
Mike

As a minimum you just need a crank spacer (the serp crank nose is much longer than your pre-serp so you need a collar to clamp the front pulley / damper on) and a 450 chip for the ECU (99% of the TVR ecus are socketed so chip change is easy) ~ ask on PH someone will likely have a chip for a 4.6 with TVR style cam.

You just wont leave me alone about thet bloody crank spacer will you Dave!


I pick my car up tomorrow with the Megasquirt sorted so i guess i will have a 450 ECU spare. It has a 500 chip i think that Eann at torqueflow fitted and with the TF AFM tuned by him to suit ran very well with excellent fuelling.

Could be an option if you are'nt too far from Warrington for the tune up.

PS. i aint asking for luck and best wishes ahead of this weekends driving to York etc as it hasnt paid off in the past.

dbv8 wrote:You just wont leave me alone about thet bloody crank spacer will you Dave!
.

It's not the same spacer as you have with the intermediate front cover you paranoid tart

spend wrote:

dbv8 wrote:You just wont leave me alone about thet bloody crank spacer will you Dave!
.

It's not the same spacer as you have with the intermediate front cover you paranoid tart

OK Girls!!!!
Calm down ........

Its OK these 2 clowns know each other

SimpleSimon wrote:Its OK these 2 clowns know each other

You calling my home Girls Clowns Dude????

This is fighting talk mate...

This could lead to a throw down of half shafts or handbags at dawn for a duel

Crank spacers can easily be ground into fighting stars you know ??

Maybe thats what Del used his last one for ????

mgbv8 wrote:

SimpleSimon wrote:Its OK these 2 clowns know each other

You calling my home Girls Clowns Dude????

This is fighting talk mate...

This could lead to a throw down of half shafts or handbags at dawn for a duel

Crank spacers can easily be ground into fighting stars you know ??

Maybe thats what Del used his last one for ????

Yes i heard the outcome of Dereks missing spacer at the Pod poor chap.

Some good and some very bad and sad news.

I got the car to York after having megasquirt fitted and mapped giving me 308 bhp and a lovely fat torque curve. The car ran 12.7 @ 108 on a cold track and ended with a 12.4 @ 111 Monday afternoon. No nitrous.

Sadly we lost a fellow racer on Sunday. Kasey was only 23 and his car lost control over the finish ine at 130 mph rolling over 10 times.
I always camped next to him and his family in the pits and shared BBQ and beers regularly.

what is the final spec of the engine?

POAH wrote:what is the final spec of the engine?

Its a TVR 4.6 crossbolted block running 4.0 ltr pistons for higher comp.
The heads are the fully ported big valve TVR 500 jobbies.
A real steel Typhoon camshaft and double springs.
Single 72mm plenum, standard injectors and run by a direct fire Megasquirt.
The exhaust was port matched and is fully decatted.
The trumpets have been removed and the base blended.

dbv8 wrote: The trumpets have been removed and the base blended.

why remove the trumpets?

POAH wrote:

dbv8 wrote: The trumpets have been removed and the base blended.

why remove the trumpets?

There is a train of thought that removing the trumpets moves the power up the rev range with some high end gains. Others believe it would be at a detrimental loss to lower down torque but my power plot is excellent IMO.

The engine came this way when i bought it and it works very well.