GT-40P heads, stock cam & 1.7 rockers?

[94GT40]

I also posted this over in the 94-95 tech section. I hope it's OK to post it here too...

I'm going with the Cobra intake, GT-40P heads, sticking with the stock cam and will be using the 1.7 aluminum roller rockers. A few questions:

1. Does anyone here have a similar combo? If so what rwhp and rwtq numbers are you putting down?

2. From what I've read I will need to use some valve covers with more clearance. Any suggestions for inexpensive valve covers?

3. Will I need to do anything special to the Cobra intake to clear these valve covers?

4. I shouldn't have any piston to valve clearance problems using the stock cam, should I?

5. I read that the 94-95 Cobra's that used the 1.7 rockers actually had a milder cam than the 94-95 GT's. Is that true? It kinda makes sense in that they were only rated at 240hp.

6. How does the "Thumper" ported heads compare with the GT-40P heads? I almost ordered the GT-40P's from Tri-State, but I'm still considering other options.

A. Tri-State modified GT-40P's 1.94/1.54 for $470 shipped
B. Thumper E7 ported heads for $595 + shipping
C. Buyfordracing GT-40Y's for $749 + shipping

What's the best bang for the buck for a low budget daily driver?

Thanks in advance for any help.

 

[25thmustang]

I posted my reply there, about my dads 91. But he also uses stock valve covers!

 

[BaXTeR3221]

I run 1.7's on my car with the stock valve covers. Unless the heads require a different set, which i doubt, you should be fine w. the stock ones.

 

[94GT40]

I run 1.7's on my car with the stock valve covers. Unless the heads require a different set, which i doubt, you should be fine w. the stock ones.

Thanks... Did you have to modify anything on the inside. What do you think of the Proform rockers? I hear that they are good quality for the price.

 

[notchback]

w/ those head choices , i would buy the p's

port the crap out of them....exhaust mainly...some intake work, and remove the bump

should be good for 300 hp w/ the port work...275 w/ out

 

[BaXTeR3221]

Thanks... Did you have to modify anything on the inside. What do you think of the Proform rockers? I hear that they are good quality for the price.

I didn't actually put the rockers on the car, they were there when i bought them. I had thought they were stock cobra roller rockers, but they are actually crane cams. I dont know how much difference they make on my car since its mostly stock, but i would think with an intake and heads, the extra lift would be helpful since your staying with the stock cam.

 

[Paul Perreca]

the 4.6L tech has a section titled, "Modification Survey Thread " and this is what we should have in the 5.0 tech section as well, i would be very interested in seeing everyones combos and thoughts about parts !!!!!! I dont want to be the one to start it though, because I don't know how to get it to be a sticky, but we should have a sticky over here!!!!!!

 

[shewitt]

I have heard from people that its not a good idea to go with 1.7 with gt40p heads. But at the same time people told me not to use a supercharger with my gt40p heads.

 

[94GT40]

I have heard from people that its not a good idea to go with 1.7 with gt40p heads. But at the same time people told me not to use a supercharger with my gt40p heads.

A tech article in "5.0 Mustang" magazine said that the 1.7 rockers with the stock cam was "ideal" with the GT-40P heads.

 

[twolo4u2c2]

OK.....I have almost the same config before I went with a 347. Only difference is an e-cam & I have the gt40 intake(pretty close to the cobra). I made 267hp and 315 tq at the rear wheels and my 302 had 170k on the ticker. thought that was pretty good. oh My gt40p has 190/164 valves to so I guess it not real close but I hope it helped.

 

[OL' WHITEY]

My car made 236hp / 386 tq. with stock cam, stock E7 heads, 1.7's and a cobra intake. Also 70mm tb, 73mm mass air and shorty headers (see sig.). 128K on the ticker! P heads should get you another 20-30 hp at least.

 

[shewitt]

Im just going by what people have wrote on this board about 1.7 and gt40p's.

 

[94GT40]

Im just going by what people have wrote on this board about 1.7 and gt40p's.

I'm gonna take the risk. The 1.7's are easy to change back to 1.6's, and I can sell the 1.7's on eBay.

 

[5.0alltheway]

im running 40ps ported polished,1.7s ,stock cam,mac headersw/a carb and 410s,this thing pulls very strong up to 6000,cant complain at all.

 

[5.0alltheway]

im running 40ps ported polished,1.7s ,stock cam,mac headersw/a carb and 410s,this thing pulls very strong up to 6000,cant complain at all.oh yeah ,mine have been milled .040 w/o clearance probs

 

[Mike86Stang]

FWIW I think the Gt-40p's would be the best choice of the bunch you posted....

Mike

 

[94GT40]

im running 40ps ported polished,1.7s ,stock cam,mac headersw/a carb and 410s,this thing pulls very strong up to 6000,cant complain at all.oh yeah ,mine have been milled .040 w/o clearance probs

Thanks for the reply... I'm headed to the post office to get a money order and sending off for the heads right now. Starting to get pretty stoked. I'm anxious get them on with the other stuff, drive it and get the dyno numbers.

I'm curious to see how the larger valves will affect performance compared to others with similar combos.