First issue is that the car only made 320 rwhp and 290lbstq on a Mustang dyno. This seems **** poor to me. As far as im concerned it should of made good deal more then that. Was only spun to about 6200 but come on, that seems really low does it not? Car has a full top end LE2 heads intake and custom cam 228/236 .592/.592 110lsa, 58mm bbk, 37# injectors, comp oe replacement lifters, comp Pr's, 1.6 rr's, stock shortblock. racetronix fuel pump/wire kit, somewhat of a dyno tune(basically my afr at idle and wot is set nice), new opti(delphi), new plugs, wires and coil year old, meziere HD elec water pump, 160* thermostat.


This issue is a reoccurring issue for my car it seems.
My last thread i made was about how my h/c/i bolt on's Camaro was overheating on the dyno only, but not the street

Car has not ONCE overheated before i built the topend.

Last time i was at the dyno, the car overheated during the runs. Seemed like it was fine during the low rpm's but once you started getting on it the temp. would rise very quickly and would usually come back down in a hurry also. This only happens on the dyno and given er, even 3 fans pointing at the front of the car(one right at the air dam up to the rad) and 2 fans on the top keeping the heat from the headers down also. I discovered last time that i had some relays buggered up for the fans and as of a result had no high speed fans, thats been changed and seems to be working fine now, however my problem still remains.

It will not overheat idling or sitting in traffic. It has not and won't over heat for me at all. The highest temp the car see's is MAYBE 180* , other then that it sits at about 165* when driving at anything over 30-40mph.

Today i noticed something odd. The temp. guage on the dash shot up in a hurry but the pcm reading was considerably cooler and dropping as indicated by the scantool. So for some reason, the head temp. sensor is seeing a much higher temp when its over heating then the pcm is reading. Whether or not this happens every time, i have no idea, i figured id call it safe and cut my losses so i could still drive the car home.

The car has a miss at 5800rpm, which im sure is unrelated. Car runs awesome otherwise, oil looks fine, under the valve covers looks fine. No smoke out the exhaust or anything. No milkshake anywhere that i can see. I cannot see the car still having air in the system, its been burped and cycled NUMEROUS times. I guess its still a possibility but i severely doubt it.

The theory i have is, is it possible for the water pump to be spinning the wrong way? The coolant seems to be moving nicely to the top of the rad via the steampipe connection so it appears the pump is pumping fine. Ive read of a few cases where its not wired properly from factory and the car will be fine at idle and such but call it quits when it comes time to do some serious cooling( IE dyno). Ive even thought about the thermostat sticking, but i can't see why it would only do it at the dyno and not any other time. Im also wondering if i have a proper LT1 thermostat since apparently they are different. I have a 160* in there but it was a motorad from the parts store so it may just be a reg. sbc thermostat. How much of a change would that even make?

I;m at a loss for words right now. I have no interest to keep working on the godamn thing but i want it running properly. ANY suggestions or comments will be helpful at this point. Thanks.

 

There is a hole on one side of the gasket that is not on the other. I noticed this after I did one side. I had to pull the gasket to make sure I did not mess it up. The hole is acually right by the front of the block by the stat. Sucks man but I say its the problem. and its only one of the holes so I dont think it would heat up the block until it was under high rpms. Also im going to guess that the miss fire is on 1 or 2.

 

What are you referring to in particular?

 

you have air in the system.

 

seems as if he is talking about the head gasket

 

Thats exactly what i wasnt hoping to hear. The guys at the shop asked if if we put them on right. Im 99.9% positive that we installed the gaskets with the tag saying "this side up", but to be honest i didnt notice a difference between the gaskets..

EDIT: So basically what im hearing here is that theres a specific gasket for each head and its possible i have the gaskets swapped?

 

i was talking about the head gaskets... just relized that you had a lt1. That is on a ls1 I have no clue about a lt1 but you might want to look into it.

 

This side up would not matter if its like the ls1. There is acually a right side and a left side but you can put them on backwards. This side up would not matter. Easy check, go to autozone and ask to see both and compare.

 

**** me. I dislike this game. I wish i would of ******* noticed that . Im going to be pissed if that was the problem.

 

You mention the Tstat being a generic parts store brand...check the part number and be sure its the right one.

SBC and LT1 thermostats are not interchangeable.

 

When looking at the bottom of the factory heads, they look identical except reversed. Is the difference in the block then and the gaskets or?



Thats next on my to do list. I just bought a new rad cap, going to get a thermostat, then bleed the system yet again and hope for the best.

 

Hey:

As Speed mentioned before it really does sound like you still have air in the system. As air really shows up when under demand like hard driving or dyno.

Did you bleed with the heater on, and fill with the bleed valves open or fill directly in the waterpump without the stat in, as these methods help eliminate air getting caught up in the system and spending many times bleeding afterwards. You can also pressure bleed or vacuum the system air out.

I would try this before tearing the head gaskets back apart. Also confirm you have the right T stat.

Dub

 

initially when i filled it for the first start, i filled the block through the wp slowly as much as it would take. Then filled the rad slowly as much as it would take while both bleeders were open and bubbled with coolant.. filled the res. to the cold limit, and fired it up with the bleeders opened till it was a solid stream.

I really hope its a big air pocket. Im considering getting more or less a beer bong on top of the rad filled with coolant and getting under the car and pulling the plug and knock sensor to make godamn sure theres coolant and not air down there and doing the same with the temp sensor in the head.

 

Hey:

What about the heater control inside the car was it on and heat selected as it can trap air in it.

Dub

 

coolant would circulate through the heater core regardless. the header controls only operate a door by the core that allows the fan to blow air through the core. Unless the camaro has some weird set up im unaware of.

 

Hey:

Adam1203 you are right. I don't remember the exact reason if there was any, on why to do it that way right now, but maybe by coincidence it made it a lot easier to bleed with the heater on and up to a warm temp than when I did not do it that way when I first changed out my MWP to EWP, it was on another forum/BB back then and was from some garage bulletin or something as there was a few problems back then when the car was still new with getting all the air out and this helped make it faster to bleed. Could be just BS, But I had the same thought as you back then, but someone gave me a reason that sounded logical ATT, I just don't remember all the steps and why right now.

Dub

 

when i bleed my systems i always put the car on a slight hill then put the one side with the cap on a ramp as well. it has always worked well for me. this will be my first time bleeding out the lt1 ill probably to it the same way.

 

I have had to bleed my car 3 or 4 times between driving it over the course of a few days before all the air was out.

Being reverse cooled has its drawbacks, air pockets being one of them.