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I'm looking into putting this can in my 91 stang with gt 40 heads and intake. Has anyone on here ever use this can before? Of course I'm going to check ptv clearence but this has to be hands down the best sounding little can ive heard. Any input would be appreciated
 
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hi, that cam will have very llittle bottom end, if you have an auto i would run at least 355 gears and around a 2400 rpm stall converter with it. you also need to mill your heads .025 - .028 from stock to increase compression to optimize the perf of that cam. also an increase in head And possibly intake flow over stock will greatly improve its perf. you might want to look at the comp cam in the link below as another option. it is cery easy to overcam an engine.

Comp XE270hr

compcams.com/Company/CC/cam-specs/Details.aspx?csid=1054&sb=0
 

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I somewhat disagree. I don't have first hand experience with that exact cam, but the specs are very reasonable for a GT40 headed 302 build.

I'd use 1.6 rockers. You must upgrade the valve springs!

Good luck!
 
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i was a comp cam dealer and have built and numerous engines with this type of cam. accessing perf is a subjective opinion. irregardless you need more compression.
 

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I use a TFS Stage 1 (which is very close to the cam the OP was inquiring about) with my 306 GT40-headed build. I race Solo II with the car and it made 280 RWHP last pull, but what do I know?

I'm not going to get into a ******* match, just my $0.02.
 
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All 3 cams mentioned are good cams but operate over different rpm ranges. Instead of picking a cam by sound it is better to determine exactly how you will be driving it and what your goals are like the following:

Mild, moderate or rough idle?

Mainly street, freeway or a bit of both types of driving?

Bottom end, mid range or top end perf?



Below are a portion of all 3 cams specs.

Comp xe270h 270 276 218 224 .512 .512 lsa 114 rpm 1800 – 5800

Tfs stage 1 .. 283 291 221 225 .499 .500 lsa 112 rpm 2000 – 5500

Lun 51014 ... 284 292 218 226 .500 .510 lsa 112 rpm 2500 - 6000 xxxxxxxx
 

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Discussion Starter #8
Guys I really appreciate the feedback an you both have good points. It will be just a little mild street car an everyone is telling me I should shoot for around a 3000 stall. Does that sound right? I was thinking about doing a little pirt work on the heads. I have a gt 40 tubular intake I'm sending off to tmoss
 

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I have an stock aod with 373 gears in the rear. 15" black magic electric fan, under drive pulleys, mac shorty headers with flowmaster exhaust. All the smog is off the car
 

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67cpe I am not sure why you continually keep saying everyone needs more compression. It is not like you can bolt on compression.

Also more compression is nice but not needed as all the cams will run GREAT with GT40 heads. So milling those heads is not worth it and not needed.

There are countless cars out there running those combos without the added benefit of more compression and do not thing half a point will make a world of difference either.
 
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What would it cost to mill the heads an what gains in performance? Just curious thanks
Around $30.00 each and around 3% increase of hp and toirque from 1000 to max rpm.

From the factory your engine has a dynamic compression of around 7.9 and a cyl crank pressure of around 156.5 psi. The optimum level of cyl crank pressure for a perf eng running 93 octane is between 170 and 180.

This means that from the factory, your eng has less than optimal compression for a perf eng that runs on 93 octane therefore increasing the compression on a stock engine will yield benefits.

In general, the bigger the cam the more compression that is needed to optimize that particular cams perf. Every cam mfg says this in the cams perf description however the minimum compression ratios they recommend are less than optimal.

Milling your heads .025 - .028 will increase your dyn comp from 7.9 to around 8.3 which in your case gives you a cyl cranking pressure of 167.0 psi.

In general, increasing static comp by .5 will increase your hp and tq by around 3% across the board. This is certainly not a lot but when you install your cam, your dyn comp and cyl crank comp will go back down to 7.9 and 157 which is exactly where you started in the first place which is low. This will be 6% less hp/tq from 1000 to max rpm then you would have if you increased your cyl compression to just 167. This is a very noticeable number however the only way you could do this in your particular case is to get different heads with smaller chambers or mill your block.
 
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What would it cost to mill the heads an what gains in performance? Just curious thanks
Around $30.00 each and around 3% increase of hp and toirque from 1000 to max rpm.



What is your elevation?

You loose around 5 psi of cyl pressure for every 1000 foot increase in elevation. this means that if you are 2000 feet or more above sea level your comp is extremely low.

From the factory your engine has a dynamic [not static] compression of around 7.9 and a cyl crank pressure of around 156.5 psi. The optimum level of cyl crank pressure for a perf eng running 93 octane is between 170 and 180.

This means that from the factory, your eng has less than optimal compression for a perf eng that runs on 93 octane therefore increasing the compression on a stock engine will yield benefits without putting it in danger of detonation.

In general, the bigger the cam the more compression that is needed to optimize that particular cams perf. Every cam mfg says this in the cams perf description however the minimum compression ratios they recommend are less than optimal.

Using your stock cam, milling your heads .025 - .028 will increase your dyn comp from 7.9 to around 8.3 which in your case gives you a cyl cranking pressure of 167.0 psi.

In general, increasing static comp by .5 will increase your hp and tq by around 3% across the board. This is certainly not a lot but when you install a bigger cam, your dyn comp and cyl crank comp will go back down to around 7.9 and 157 which is exactly where you started in the first place, which is low.

This will be 6% less hp/tq from 1000 to max rpm then you would have if you increased your cyl compression to just 167. This is a very noticeable number however the only way you could do this in your particular case is to get different heads with smaller chambers or mill your block.
 
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