Engine blown in my RX7, rebuild or V8?

[Papercup]

the v8 conversion as far as i know has a better weight distribution as the gearbox is heavier so pushes the weight low down in the middle of the car....suppose craig (tinker) can answer that....

its going to have to be a very heavy gearbox to counteract the extra weight of the engine, which is further forward :3Confused
 
i remain to be convinced with that argument!
 
i\'ds like to see proper corner weighting of one of these V8 cars to show:
 
1. how much extra weight there is
2. where the weight is

[Hi RX7]

Can I suggest you look at the American V8RX7 forum there are loads of threads there about this and they are facts by people who have been doing this for a while. I have just spent an hour or two reading them and I am now more than convinced that this is the way I will eventually go.

[Papercup]

\'the grass is always greener on the other side\'
 

[Hi RX7]

Well the post I read was by dcrosby.
LF774
RF730
RR802
LR758
3064 lbs total with 3/4 tank and 150lbs driver
49.1% front 50.9% rear
I do hope he doesn\'t mind me quoting these figures
It appears to have been done by a proper established Alignment Centre

[Papercup]

by my calculations, removing the driver, that makes the car over 1300kgs
 
as i\'ve said.....for a road car maybe the extra doesn\'t matter but i remain to be convinced it will handle as well as a rotary.

[BenLewisMav]

The V8 conversion adds about 100kg in weight (so said Tinker to me), and changes the weight distribution (you cannot get the V8 as low or as far back as the rotary, its why our rotary cars handle so well). The RX-7 is a true \'front mid-engined\' car; the entire engine behind the front axle. The V8 conversion is not.
 
As such, it would not be possible for the V8 car to handle as well as a rotary powered car. You would also have issues getting suspension to work well; anything you buy will be sprung and valved for a car that has 100kgs less weight over the front axle. You\'d have to get something custom sprung and damped. Even still, the extra weight and where the extra weight is positioned means the rotary will have the edge in handling.
 
I have yet to see a V8 powered car being driven hard on track. Tinker\'s car is a daily driver and the standard of work is fantastic, but i remain to be convinced that the V8 would make as good a track and race car as the rotary.
 
I\'d like to try one, and it would be a possibility if my engine let go. But i wouldn\'t go ahead until i\'d put one round a track.
 
The rotary engine is why the RX-7 is special; weight and handling balance mean so much.
 
Andy

I would agree with you up to a point, as mentioned look at craigs time attack car, is winning nearly every n/a race.. It\'s combination that works on the track, whifbitz with a rotary didnt do quite so well..

[Papercup]

I would agree with you up to a point, as mentioned look at craigs time attack car, is winning nearly every n/a race.. It\'s combination that works on the track, whifbitz with a rotary didnt do quite so well..

different class, surely?
 
What else is in the N/A class then?

[Rzla]

blah blah blah ..
regardless if you get an engine built by a good engine builder and tuned by a good tuner with the CORRECT AND NECESSARY PARTS the rotary will rip a v8 ..
and please don\'t use the time attack series as a comparison ...
the rx7 is known be one of the best track cars available for a reason .. taking the rotary out of it is ripping its heart out .. all you rotory haters who have had bad experiences need to get in contact with someone who can build an engine right and make sure you get the NECESSARY parts to keep the engine reliable .. your own incompetencies should not put the rotary down and call it unrealiable ...
and no this is not aimed at anyone specifically

[bin liner]

lets me honest here...there are very few people who push there cars to the limit when they drive...maybe they\'ll plant there foot in a straight line but not many people are confident enough to do the same on the twisy bits..most therefore prefer good straight line speed...stick with the rotary if u want the extra balance round the bends, most people want reliabilty which the rotary certainly isn\'t when specced up...if mine blows up then theres only one way forward...v8..i\'m happy to sacrifice a bit of balance for reliabilty...anyway v8\'s are great for going up the road sideways....

[Rzla]

I would agree with you up to a point, as mentioned look at craigs time attack car, is winning nearly every n/a race.. It\'s combination that works on the track, whifbitz with a rotary didnt do quite so well..

oh please don\'t use that crap comparison .. drivers are more important than the cars .. put a good driver in a **** car he can make it look good ..
whifbitz is in a class with the big tuners who just put a new engine in every race and get new parts for cheap .. there is a big difference ..
i am telling you if an ex race driver was put in whifbitzs car that thing would demolish everything in its view ..
touge time attack was won by the rx7 ahead of the gtrs and the scoobys and the evos ...
i think that is a better place for comparison don\'t you agree ? similar drivers with similar capabilties

[Papercup]

most people want reliabilty which the rotary certainly isn\'t when specced up...

this is not true.
 
If they are built right they can be reliable, mine\'s been fine and i track and race it and have done for over a year and a half. I\'m winning stuff as well. Max and are racing in the Nippon series, Atomic Rex races his. Ask them whether reliability is an issue.
 
People buy ****ed RX-7s off each other and blame the engines when they let go immediately. Then they get it rebuilt cheaply by \'bloke down the road\' and whine some more when it pops again.
 
I am genuinely interested in how a V8 car handles, and whether the undeniable extra weight ruins the balance of one of the best track cars available. I suspect it makes a very different car, one that may not feel like an RX-7 any more, though it will still be very good in many ways. Hopefully I\'ll catch up with Craig soon at a trackday and have a go in his; he has offered.
 
Oh, and the simplistic internet answer of \'throw a V8 in it and life will be happy for ever\' is insulting. All custom built cars have issues.
 
Andy

[bin liner]

this is not true.
 
If they are built right they can be reliable, mine\'s been fine and i track and race it and have done for over a year and a half. I\'m winning stuff as well. Max and are racing in the Nippon series, Atomic Rex races his. Ask them whether reliability is an issue.
 
People buy ****ed RX-7s off each other and blame the engines when they let go immediately. Then they get it rebuilt cheaply by \'bloke down the road\' and whine some more when it pops again.
 
I am genuinely interested in how a V8 car handles, and whether the undeniable extra weight ruins the balance of one of the best track cars available. I suspect it makes a very different car, one that may not feel like an RX-7 any more, though it will still be very good in many ways. Hopefully I\'ll catch up with Craig soon at a trackday and have a go in his; he has offered.
 
Oh, and the simplistic internet answer of \'throw a V8 in it and life will be happy for ever\' is insulting. All custom built cars have issues.
 
Andy

whatever floats your boat...why your getting so hot under the collar i dont know...i know of 4 cars right now that have been built by recognised tuners and engine builder that have gone belly up in under 8k within 12 months, with the right parts used...You cant blame people for wanting more reilabilty...i understand some rotaries are proving themselves....but at 60k or so u are gonna need a rebuild.. i have still got my t78 powered rx rebuilt from from the ground up using all new parts that was built by me and my mate still going strong, if it blows i\'ll sell the engine bits and turbo and try V8...  handling wise i have a porsche boxster S, not the quickest but drives suberb, and now an abt Audi TT soon to be on the road having just completed a custom hybrid conversion...i understand all custom cars have issues i have built a couple but the debate of the rotary being reliable/unreliable is one that cant be won...its like marmite....u love it or you hate it....me, im on the fence....

[Papercup]

whatever floats your boat...why your getting so hot under the collar i dont know...i know of 4 cars right now that have been built by recognised tuners and engine builder that have gone belly up in under 8k within 12 months, with the right parts used...You cant blame people for wanting more reilabilty...i understand some rotaries are proving themselves....but at 60k or so u are gonna need a rebuild.. i have still got my t78 powered rx rebuilt from from the ground up using all new parts that was built by me and my mate still going strong, if it blows i\'ll sell the engine bits and turbo and try V8... handling wise i have a porsche boxster S, not the quickest but drives suberb, and now an abt Audi TT soon to be on the road having just completed a custom hybrid conversion...i understand all custom cars have issues i have built a couple but the debate of the rotary being reliable/unreliable is one that cant be won...its like marmite....u love it or you hate it....me, im on the fence....

Not sure where i am getting hot under the collar? Feel free to point it out.

[BenLewisMav]

oh please don\'t use that crap comparison .. drivers are more important than the cars .. put a good driver in a **** car he can make it look good ..
whifbitz is in a class with the big tuners who just put a new engine in every race and get new parts for cheap .. there is a big difference ..
i am telling you if an ex race driver was put in whifbitzs car that thing would demolish everything in its view ..
touge time attack was won by the rx7 ahead of the gtrs and the scoobys and the evos ...
i think that is a better place for comparison don\'t you agree ? similar drivers with similar capabilties

Yeah thats a fair comparison (touge)..  Please don\'t misunderstand, I\'m rotary through and through, I was just trying to point out that it is a good combination that has a lot of potential.
Of course you only have to look at AtomixRex\' car to see what a well built rotary powered beast is capable. I really don\'t want this to turn into another V8 or rotary thread.

[Spartacus]

Most of these conversions are in the US and from what I’ve read the owners of these cars, many of whom have raced them both before and after the conversion state that they are unable to feel a difference in handling. Maybe we should listen to those with experience of racing the FD before and after the conversion as I would have thought that they are the only people whose opinions really count?

As for the weight issue, how many of our cars have not been modified in any way affecting the weight?
There are many of these conversions where the car comes out lighter than the original.
To get a true comparison would be almost impossible.