7m Cams

[suprastroker88]

I'm putting together a built 7m. I have a built head which includes full CnC, ported, polished, 3 angle valve job, etc. Only thing I'm missing is cams. My goal is to put together a low 11s to high 10s motor. I have a set of stock cams that i would like to have a custom regrind done to but I dont know to what specs i should have them done.

My question is, are any of you using stock regrinds for dragging your 7m and if so, what specs? as in duration and etc? Sorry, Im new to this

 

[carmsbody]

talk to the shop who will be doing the grind, tell them your engine specs, goals and intended use of the car and they will choose a profile that will suit you. the bigger the shop the better as they will have a wider selection of profiles to choose from

 

[bioskyline]

+1 on that. or at the very least if they dont have the right profile for a re-grind, they should be able to recommend someplace that can, or which ones off the shelf to buy.

 

[IBoughtASupra]

You should use a set of cams that will suit your turbo. If you have a turbo with a big A/R, that means higher top end power and lag down low. Smaller A/R means less lag but less top end power. You should choose a cam that will suit the turbo based on the A/R. 272's are good for top end but the head will need modification and shimless buckets which Toyota sells for the MR2.

264's and lower are good for mid-range power but I am not sure if I have seen a 264 cam for the 7M. Look around, maybe BC or Crower has some.

 

[suprarich]

Lift makes top end power. Not duration. Lag can be adjusted by cam timing. How can you say a 272 advertised duration cam will need shimless buckets if you have no idea how big the cam is to begin with?

 

[IBoughtASupra]

Lift makes top end power. Not duration. Lag can be adjusted by cam timing. How can you say a 272 advertised duration cam will need shimless buckets if you have no idea how big the cam is to begin with?

I am not the cheap MK3 owner and with that long of a duration I always run spring, retainers and shimless buckets.

The OP posted that he wanted a 10-11 second car. With this, I assumed he will be going to the track. I also assumed he will be making a few trips into the upper RPM range, 4000+. With that many trips into high RPM, you should run shimless buckets because the risk of throwing a shim out is very high and running tighter clearances is the cheap and not the way.

Modifiy the head was stated because I was warning him with bigger cam, that might be needed. I forgot the add that depends on lift as well. I was not wrong, just forgot to type that it will need to be modified with higher lift cams.

 

[suprastroker88]

Thanks for the input. Please keep them coming.

The shop I'm using is http://www.rebelloracing.com/ He said he's done a few 7m's but he is more of a nissan specialist. But he cam regrind price is cheaper than I've found anywhere. So with that being said, that's why I've come back to the Supra World to get opinions and options.

As i mentioned, the head has the following.....
Fully CnC'd
Port and Polish
BBC springs

And I am planning on either running the Driftmotion 67mm turbo kit or maybe somethin like a PHR T4 Stage 2.

 

[IBoughtASupra]

I recommend the DriftMotion kit....I have used the 7M one before. It is an EBay manifold that is modified to be better but the turbo is top quality. 5000+ miles of hard driving and been on two engines and it is still going strong. No smoking. You will need their coolant bypass line if you go with a oil cooled turbo.

 

[suprastroker88]

I recommend the DriftMotion kit....I have used the 7M one before. It is an EBay manifold that is modified to be better but the turbo is top quality. 5000+ miles of hard driving and been on two engines and it is still going strong. No smoking. You will need their coolant bypass line if you go with a oil cooled turbo.

Ok thanks. Ive been looking to find someone that has used these driftmotion turbos and haven't found anyone until you. Where did you see full boost and what were your mods?

 

[suprarich]

I am not the cheap MK3 owner and with that long of a duration I always run spring, retainers and shimless buckets.

The OP posted that he wanted a 10-11 second car. With this, I assumed he will be going to the track. I also assumed he will be making a few trips into the upper RPM range, 4000+. With that many trips into high RPM, you should run shimless buckets because the risk of throwing a shim out is very high and running tighter clearances is the cheap and not the way.

Modifiy the head was stated because I was warning him with bigger cam, that might be needed. I forgot the add that depends on lift as well. I was not wrong, just forgot to type that it will need to be modified with higher lift cams.

Was just pointing out to anyone reading this thread that the advertised duration of a cam has little to no meaning when it comes to the size or power potential of a cam. Not all 270+ advertised duration cams will "need" a valve train upgrade. For example, a 7.7mm lift 274 or 278 duration cam needs nothing, but a 11.5mm lift 256 duration cam needs 28mm shimless buckets, dual springs, TI retainers, steel locs, and a whole bunch of the head casting milled out just so they will be able to swing.

 

[suprastroker88]

Was just pointing out to anyone reading this thread that the advertised duration of a cam has little to no meaning when it comes to the size or power potential of a cam. Not all 270+ advertised duration cams will "need" a valve train upgrade. For example, a 7.7mm lift 274 or 278 duration cam needs nothing, but a 11.5mm lift 256 duration cam needs 28mm shimless buckets, dual springs, TI retainers, steel locs, and a whole bunch of the head casting milled out just so they will be able to swing.

Ok so do you have any input on the right regrind I should be looking towards?

 

[suprarich]

No, I really don't know enough about your set up to say. But Iboughtasupra already hit the nail on the head. You want to size your cam and head flow/velocity to match the turbo you will use and to where you may want your most usable and desirable power band. At the power level you want, you are just on the edge of where a cam upgrade will help somewhat. Not much to gain on anything under 400 hp. Just keep in mind, you don't need cam upgrades to run the power and times you want.

 

[suprastroker88]

No, I really don't know enough about your set up to say. But Iboughtasupra already hit the nail on the head. You want to size your cam and head flow/velocity to match the turbo you will use and to where you may want your most usable and desirable power band. At the power level you want, you are just on the edge of where a cam upgrade will help somewhat. Not much to gain on anything under 400 hp. Just keep in mind, you don't need cam upgrades to run the power and times you want.

ok thank you. and thanks to everyone one else for their input also

 

[CT26smoker]

If you go regrinds, where the cam grinder isn't welding them up first, you end up needing very thick shims,
and the nose profile of the cam is less than what is desirable, because there just isn't enough material to put much of a profile on a stock cam.

 

[Mike Morris]

What kind of engine management are you running? Speed density set ups with big cams can be a tuning cold start nightmare fyi

 

[Jimbo]

Aren't you selling that head right now on craigslist?

 

[laotionracer101]

If you go regrinds, where the cam grinder isn't welding them up first, you end up needing very thick shims,
and the nose profile of the cam is less than what is desirable, because there just isn't enough material to put much of a profile on a stock cam.

Yeah i was thinking the same thing, im pretty sure he is getting them welded though but ive heard horror stories about this kind of thing,
Welds breaking off! DUN DUN DUNNN! :yikes:

 

[suprastroker88]

Aren't you selling that head right now on craigslist?

its posted, but i havent got any hits. not really trying to sell it. just wanted to see if I'd get any hits on it. If I do sell it, I have a complete 2jz waiting for me for $1000. So that's why I priced the head so high on craigslist. So therefore I most likely wont sell it but if I do, I'll have all the money for the 2jz.

In the meantime, it's under the knife!

After reading all the responses to this thread, I've decided to just buy some Brian Crowers. I have a friend with a wholesale account, so it'll be a little bit cheaper

 

[hvyman]

There are 264 cams for 7m.

Iirc suprarich does regrinds. He also makes his own custom cams. He would be the guy to give a ring if you really wanted cams.

 

[suprastroker88]

What kind of engine management are you running? Speed density set ups with big cams can be a tuning cold start nightmare fyi

Havent decided on this. I was considering a MAFT-PRO, but I'm more interested in using the MAP-ECU2, but they havent made a plug-n-play harness for it to connect to the 7m ecu yet, so I'd have to read up on how to make it work. I just dont have the money to go standalone yet