Buildiing a durable 7mge???

[nickg]

I'm new to the forums as of about 5 minutes ago. Four of my friends and I run a 1986.5 Mk111 Supra with a 7mge non-turbo in the 24 hours of Lemons. The first two races were on a really small track (which was not so great), then we did one a few weeks back at New Hampshire Motor Speedway and the end of our day came on Saturday afternoon when our engine threw a rod through the oil pan. A lilttle research on the web leads me to think that this is not uncommon with these engines.

We are in the midst of deciding whether to put in another 7mge or to swap to something else. In our minds, it has to be reliable first, fast second.

If we get another 7mge and rebiuld it, will balancing the lower end give us the reliability we are looking for or are these engines inherently weak?

What can be done to ensure a reliable engine that wasn't done to the stock one?

We would consider any engine/tranny swap as long as it is relatively easy, cheap, fast, and reliable. The end result has to be at least as fast as the original. Will a small block v8 fit???? Taurus sho v6???

To be honest, we're leaning towards building another 7mge if we can make it reliable. If we do, we will then be looking to maybe get the cam ground, maybe a llittle head porting??? Any cheap, effective engine build tips would be appreciated.

Anyone out there that knows all there is to know about the 7mge.....we need to talk.

Please reply....our crapbox racing career depends on it.

Nick

 

[Supracentral]

Read this 1st:

http://www.supramania.com/forums/sh...ttle-help-if-you-could...&p=534193#post534193

Then this:

http://www.supramania.com/forums/sh...read.-((NWS-potential))&p=1265349#post1265349

This may help as well:

http://www.supramania.com/forums/showthread.php?16034-how-much-hp-for-boring&p=182731#post182731

A lot of that references the turbo motor, but the basics apply to the NA version as well.

Yes, a small block will fit in the MA70 chassis - LS1 will as well, but that's a completely different topic.

 

[AJ'S 88NA]

Had the same problem with mine, hard turns, hard breaking, rod or two gets starved for oil. Extra quart over full may help.

I extended my oil pan and pick up by 2", added baffles, and still run an extra quart over. So far so good.

There are some good rebuild stickies, read all of them and pay close attention to increasing oil flow, pressure, and temperature control.

I went with larger clearances with my rod and main bearings, a few will say go tighter, my feelings on this is when you're out on a track really "winging it", I would like to have more oil in those areas instead of a thinner layer of protection.

 

[MA70 Ed]

i believe it all depends on previous maintenance. mine is close to 200k miles and all that's happened is the headgasket blew. i'm not very friendly with it either, and it's seen the track a couple times. still running strong!

 

[mk3_7m]

Well if you have a limitless budget and if strokers are permitted. These guys and have it assembled and built to your standard.

http://www.importperformanceparts.net/imports/strokerkits_toyota2.html

 

[IJ.]

Well if you have a limitless budget and if strokers are permitted. These guys and have it assembled and built to your standard.

http://www.importperformanceparts.net/imports/strokerkits_toyota2.html

Lemons cars are on a very tight/strict budget.

Probably be able to do a junkyard LS swap.

 

[AJ'S 88NA]

Well if you have a limitless budget and if strokers are permitted. These guys and have it assembled and built to your standard.

http://www.importperformanceparts.net/imports/strokerkits_toyota2.html

What I have plus a few other things, only thing 259 hp NA must be at the flywheel.

 

[mecevans]

1uz would be my choice.

 

[nickg]

Hi guys...thanks for the replies. As was noted, lemons cars are on a very strict budget. We will probably have to go over budget and get docked a number of laps but that will probably only apply to the first race after rebiuld.
What I was really looking for is references to a shop familiar with these engines that can do the head work (maybe with a little porting) at a reasonable price.
Also seeking info on cam grind....who should I send it to that has the specs all figured out to get the best performance with the limited other work we are doing.
I'm not familiar with searching on these forums....can someone tell me specifically where to find the threads that refer to oil pressure and temperature that AJ refered to?
Much thanks,
Nick